People

Yasuko Rikihisa

PhD, Member, National Academy of Sciences

Distinguished University Professor

Contact

rikihisa.1@osu.edu (614) 292-9677 Goss Laboratory
1925 Coffey Road
Columbus, OH 43210
Map Link

Department

Veterinary Biosciences

Professional Training and experience

PhD (1977), MS, University of Tokyo
Postdoctoral Fellow, Harvard Medical School

Research Interests

Understanding the molecular pathogenic mechanisms of ehrlichiosis/anaplasmosis, vector-borne emerging infectious diseases of man (zoonosis) and animals.
Elucidation of Ligand and Receptor, and Invasion Mechanisms of Intracellular Bacteria.
Determination of Nutritional Virulence of Intracellular Bacteria-Hijacking Autophagy Pathway by Bacterial Molecules Secreted by Type IV Secretion System.
Analysis of Regulation of Intracellular Growth and Development by Bacterial Two-component Regulatory System.
Investigation of Ehrlichia strain-variable Disease Pathogenesis In vivo Virulence Linked to Comparative Genome Sequence and Transcriptome Analysis
Isolation, and Molecular and Antigenic Characterization of New Ehrlichia, Anaplasma, and Neorickettsia spp., Aegyptianella and Haemotropic Mycoplasma.
Test Disease Intervention Strategy by using Animal models of Potomac horse fever, canine ehrlichiosis, human monocytic ehrilichiosis, and human granulocytic anaplasmosis.
Development of Vaccines and Diagnostic Procedures: PCR, dot blot, Western blot, IFA, ELISA, culture isolation, cloning protective and diagnostic antigens.
Analysis of Molecular Mechanisms of Vector (tick, trematode) transmission, and determination of Natural Reservoirs.

Department Membership

Chair, Department Promotion and Tenure Committee
Postdoctoral Training Program in Mouse Pathobiology
DVM/Ph.D. Student training program

College Membership

College Promotion and Tenure Committee

University Membership

Medical Scientist Training Program, College of Medicine
Molecular Cellular and Developmental Biology Graduate Program
Microbiology Department Graduate Program
Comprehensive Cancer Center Program
Distinguished University Scholar Selection Committee
Distinguished University Professor Selection Committee
Presidents and Provosts Advisory Committee (PPAC)

Professional Service

National Institutes of Health, Bacteriology and Mycology-1 Regular Member 1999 - 2000
Grayson-Jockey Club Research Advisory Committee Regular Member 1998 - 2000
National Institutes of Health, Microbiology and Infectious Diseases Research Regular Member 1995 - 1999
United States Department of Agriculture, Grant Review Regular Member 1988 - 2000

Clinical Service

Potomac horse fever and canine ehrlichiosis diagnostics (PCR, sero and culture isolation)

Teaching

VM6550 Comparative Biology of Disease (Core) Team leader, and Section of Bacteriology
VM530 Functional Histology (Core) Section of Cell
VM540 Structure and Function of Cells (1987-1994)
VBS693 Individual Studies
VBS850 Research Seminar in Veterinary Biosciences
VBS999 Research in Veterinary Biosciences

Graduate Training

Category III Graduate Faculty status

Graduate Training Record

30 Post Doctoral Students
24 PhD Students
6 MS Students

Honors and Awards

2012-present Elected, Member of the National Academy of Sciences
2011 The 2011 Innovator of the Year Award, OSU
2009-pesent Elected, American Academy of Microbiology Fellow
2005-present Elected, The American Association for the Advancement of Science (AAAS) Fellow
2004-2007 David White Research Award, OSU, CVM
2001 Teaching Excellence Award for Graduate Education (OSU/CVM)
1999 Distinguished Scholar Award, OSU
1997 Pfizer Animal Health Award for Research Excellence (OSU/CVM)
1992 Smith Kline-Beecham Award for Reseach Excellence (OSU/CVM)

Academic and Professional Honors

Honorary Member, American Society for Rickettsiology
The Society elect to honorary membership such persons who are deemed deserving of this honor on the basis of contributions to the fields of interest and endeavor encompassed by the purposes of this Society. Honorary membership shall be a lifetime membership and shall not require payment of dues or Conference registration fees.

American Society for Rickettsiology

2019

Recognition of Reaching a key Commercialization Milestone in 2018

Total Royalty Received from the Rikihisa’s patents and licenses by The Ohio State University

(No.1 at OSU)

The Ohio State University Cooperate Engagement Office

2019

UK Kennel Club Charitable Trust International Canine Health Awards

The International Award will be presented to an individual who is currently involved in world class innovation but with much still to contribute. The Award prize fund is intended to finance future projects and to reward the winner's outstanding contribution in the field of canine health and welfare. The Prize Fund offered for this award is £40,000.

The Kennel Club Charitable Trust Supported by Vernon and Shirley Hill, London, UK

2018

Stanton Youngberg Endowed Professor in Veterinary Medicine

The college’s first endowed faculty position and was established in 1973 for recognition of research, successful commercialization, and longstanding contributions to college

The Ohio State University

Election by The College of Veterinary Medicine

2016-2020

National Academy of Inventors

Elected for having demonstrated a highly prolific spirit of innovation in creating or facilitating outstanding inventions that have made a tangible impact on quality of life, economic development, and the welfare of society

National Academy of Inventors

Election by The NAI Fellows Selection Committee

2015

Distinguished University Professor

The permanent, honorific title of Distinguished University Professor on a competitive basis to full professors who have truly exceptional records in teaching, in research, scholarly or creative work, and in service

The Ohio State University

Election by The Office of Academic Affairs

2014

National Academy of Sciences

Elected for distinguished scientific and engineering research dedicated to the furtherance of science and technology and to their use for the public good

National Academy of Sciences

Election by Current Members

2012

Innovator of Year 2011

Recognize an Ohio State researcher who is working actively to promote commercialization of university intellectual property, through invention disclosures filed, patents applied for and/or received, technologies licensed, or spinoff companies formed

The Ohio State University

Election by The Office of Research

2011

Japan Society of Promotion of Science

Award for Lectures

Lectures at University of Tokyo, National Institutes of Infectious Diseases, University of Osaka, University of Hokkaido, Japan

2010

(October 8-30)

Fellow American Academy of Microbiology

Elected for pioneering studies entail the molecular and cellular mechanisms of invasion and survival of intracellular bacteria, concentrating mainly upon Ehrlichia, Anaplasma and Neorickettsia.

American Society for Microbiology (AAM)

Election by AAM Council after nomination

by three AAM Fellows

2009

Fellow of AAAS (Biological Sciences)

Elected for distinguished contributions to the field of rickettsiology,

particularly for fundamental studies of the cellular and molecular biology of

Ehrlichia, Anaplasma, and Neorickettsia species

American Association for the

Advancement of Science (AAAS)

Election by AAAS Council after nomination

by three AAAS Fellows

2005

David White Research Award

OSU College of Veterinary Medicine

(provides faculty awardee with support for a postdoctoral fellow for 3 years, $210,000)

College of Veterinary Medicine

The Ohio State University

2004-07

Teaching Excellence Award for Graduate Education

College of Veterinary Medicine

The Ohio State University

2001

Human Science Foundation, Emerging and Reemerging Infectious Diseases Award for Lectures

Lectures at University of Nagoya, University of Kagoshima, Conference on Tick-borne Diseases, and Meeting of Veterinary Microbiology, Japan

2000

(June 28-July 11)

Distinguished Scholar Award

The Ohio State University

1999

Pfizer Animal Health Award for Research Excellence

The Ohio State University

College of Veterinary Medicine

1997

Japan Society of Promotion of Science

Award for Lectures

Lectures at University of Azabu, National Institutes of Infectious Diseases, University of Kanazawa, University of Niigata, Japan

1997

(July 1- August 28)

Smith Kline-Beecham Award

for Research Excellence

The Ohio State University

College of Veterinary Medicine

1992

Asian American Honoree

The Ohio State University

1992

World Bank Higher Education XVII, Award

Sponsored by Midwestern Universities Consortium for International Activities, Inc. (MUCIA) for consultation and lectures at Inter-University Center in Biotechnology, Indonesia

1989

(Nov.1-30)

Teaching Excellence Award

College of Veterinary Medicine,

Virginia Polytechnic Institute and State University

1984

Publications

Budachetri, K., M. Lin, Q. Yan, R. C. Chien, L. D. Hostnik, G. Haanen, M. Leclèred, W. Waybright, J. D. Baird, L. G. Arroyo, and Y. Rikihisa (2022) Real-Time PCR Differential Detection of Neorickettsia findlayensis and N. risticii in Cases of Potomac Horse Fever. J. Clin. Microbiol. e0025022.
Rikihisa, Y. (2022) The “Biological Weapons” of Ehrlichia chaffeensis: Novel Molecules and Mechanisms to Subjugate Host Cells. Front. Cell. Infect. Microbiol. 11: 11: 830180. [PMCID: PMC8834651]
Huang, W, Q. Xiong, M. Lin, Rikihisa Y. (2021) Anaplasma phagocytophilum Hijacks Flotillin and NPC1 Complex To Acquire Intracellular Cholesterol for Proliferation, Which Can Be Inhibited with Ezetimibe. mBio. 12: e022992 [PMCID: PMC8546544]
Arroyo, L.G., A. Moore, S. Bedford, D. E. Gomez, O. Teymournejad, Q. Xiong, K. Budachetri, H. Bekebrede, Y. Rikihisa, J. D. Baird (2021) Potomac Horse Fever in Ontario: Clinical, Geographic and Diagnostic Aspects. Can. Vet. J. 62: 622-628. PMID: 34219771
Yan, Q., W. Zhang, M. Lin, O. Teymournejad, K. Budachetri, J. Lakritz, and Y. Rikihisa. (2021) Iron Robbery by Intracellular Pathogen Via Bacterial Effector–induced Ferritinophagy. Proc. Natl. Acad. Sci. 118: e2026598118. [PMCID: PMC8201858]
Zhang, W., M. Lin, Qi Yan, K. Budachetri, L. Hou, A. Sahni, H. Liu, Nien-Ching Han, J. Lakritz, D. Pei, and Y. Rikihisa (2021) An Intracellular Nanobody Targeting T4SS Effector Inhibits Ehrlichia Infection. Proc. Natl. Acad. Sci. 118: e2024102118. [PMCID: PMC8106314]
Duan, N., X. Ma, H. Cui, Z. Wang, Y. Feng, Z. Chai, J. Yan, X. Li, Y. Jin, F. Bai, W. Wu, Y. Rikihisa and Z. Cheng. (2021) Insights into the regulatory mechanism of the P28-OMP outer membrane protein differential expression in obligatory intracellular pathogen Ehrlichia chaffeensis. Emerg Microbes Infect. 2021 Dec;10(1):461-471. doi: 10.1080/22221751.2021.1899054. PMID: 33660592
Klionsky, D.J., ---H. Niu, Y. Rikihisa---- >50 others (2021) Guidelines for the Use and Interpretation of Assays for Monitoring Autophagy (4th edition) Autophagy. 2021 Jan;17(1):1-382. doi: 10.1080/15548627.2020.1797280. Epub 2021 Feb 8. PubMed PMID: 33634751; PubMed Central PMCID: PMC7996087.
Lin, M., Q. Xiong, M. Chung, S. C. Daugherty, S. Nagaraj, N. Sengamalay, S. Ott, A. Godinez, L. J. Tallon, L. Sadzewicz, C. Fraser, J. C. D. Hotopp, and Y. Rikihisa (2021) Comparative Analysis of Genome of Ehrlichia sp. HF, a Model Bacterium to Study Fatal Human Ehrlichiosis. BMC Genomics. 22: 1-22. BMC Genomics. 2021 Jan 6;22(1):11. doi: 10.1186/s12864-020-07309-z. PMID: 33407096
Budachetri, K, O. Teymournejad, M. Lin, Q. Yan, M. Mestres-Villanueva, G. N. Brock, and Y. Rikihisa. (2020) An Entry-Triggering Protein of Ehrlichia Is a New Vaccine Candidate against Tick-borne Human Monocytic Ehrlichiosis. mBio. 11: e00895-20. [PMCID: PMC7387794]
Teymournejad, O. and Y. Rikihisa (2020) Ehrlichia chaffeensis Uses an Invasin to Suppress Reactive Oxygen Species Generation by Macrophages in CD147-Dependent Inhibition of Vav1 and Rac1 Activation. mBio. 11: e00267-20 [PMCID: PMC7175088]
Lin, M., G. Grandinetti, L. Hartnell, D. Bliss, S. Subramaniamb, and Y. Rikihisa (2020) Host Membrane Lipids Are Trafficked to Membranes of Intravacuolar Ehrlichia chaffeensis. Proc. Natl. Acad. Sci. 117: 8032-8043.
Bekebrede, H., M. Lin, O. Teymournejad, and Y. Rikihisa (2020) Discovery of in vivo Virulence Genes of Obligatory Intracellular Bacteria by Random Mutagenesis. Front. Cell. Infect. Microbiol. 10: 1-16.
Teymournejad, O, M. Lin, H. Bekebrede, A. Kamr, R. E. Toribio, L. G. Arroyo, J. D. Baird, and Y. Rikihisa (2020) Isolation and molecular analysis of a novel Neorickettsia species that causes Potomac horse fever. mBio. 11: e03429-19. (Validation List 195, International Journal of Systematic and Evolutionary Microbiology 2020, 70: 4844-4847).
Xiong, X., M. Lin, W. Huang, and Y. Rikihisa (2019) Infection by Anaplasma phagocytophilum requires recruitment of LDL-cholesterol by flotillin. mBio. 10: e02783-18. [PMCID: PMC6437059]
Yan, Qi, M. Lin, W. Huang, O. Teymournejad, J. M. Johnson, F. A. Hays, Z. Liang, G. Li, and Y. Rikihisa (2018) An Ehrlichia type IV secretion system effector Etf-2 binds to active RAB5 and delays endosome maturation. Proc. Natl. Acad. Sci. 115: E8977-E8986. [PMCID: PMC6156607]
Rikihisa, Y. (2018) Role and Function of Type IV Secretion Systems in Anaplasma and Ehrlichia species. In: Type IV secretion in Gram-negative and Gram-positive bacteria. Ed. Steffen Backert & Elisabeth Grohmann. “Current Topics in Microbiology and Immunology” (CTMI) by Springer International Publishing AG Switzerland. 413: 297-321.
Teymournejad, O., M. Lin, and Y. Rikihisa (2017) Ehrlichia chaffeensis and Its Invasin EtpE Block Reactive oxygen Species Generation by Macrophages in a DNase X–Dependent Manner. mBio. 8: e01551-17. DOI: 10.1128/mBio.01551-17. PMID: 29162709
Rikihisa, Y. (2017) Subversion of RAB5-Regulated Autophagy by the Intracellular Pathogen Ehrlichia chaffeensis. Small GTPase. 0: 1-7. PMID: 28650718 DOI: 10.1080/21541248.2017.1332506
Sharma, P., O. Teymournejad, and Y. Rikihisa (2017) Peptide Nucleic Acid Knockdown and Intra-Host Cell Complementation of Ehrlichia Type IV Secretion System Effector. Front. Cell. Infect. Microbiol. 7: 228 PMCID: PMC5461285 DOI: 10.3389/fcimb.2017.00228
Lin, M., K. Bachman, Z. Cheng, S.C. Daugherty, S. Nagaraj, N. Sengamalay, S. Ott, Al Godinez, L. J. Tallon, L. Sadzewicz, C. Fraser, J. C. Dunning Hotopp, and Y. Rikihisa. (2017) Analysis of Complete Genome Sequence and Major Surface Antigens of Neorickettsia helminthoeca, Causative Agent of Salmon Poisoning Disease. Microb. Biotechnol. 10:933-957. DOI: 10.1111/1751-7915.12731
Pritt, B.S., Allerdice M. E. J., L. M. Sloan, C. D. Paddock, U. G. Munderloh, Y. Rikihisa, T. Tajima, S. M. Paskewitz, D. F. Neitzel, D. K. H. Johnson, E. Schiffman, J. P. Davis, C. S. Goldsmith, C. M. Nelson, S. E. Karpathy. (2017) Proposal to reclassify Ehrlichia muris as Ehrlichia muris subsp. muris subsp. nov. and description of Ehrlichia muris subsp. eauclairensis subsp. nov., a newly recognized tick-borne pathogen of humans Int. J. Syst. Evol. Microbiol. 67:2121-2126. doi: 10.1099/ijsem.0.001896
Kumar, N., M. Lin, X. Zhao, S. Ott, I. Santana-Cruz, S. Daugherty, Y. Rikihisa, L. Sadzewicz, L. J. Tallon, C. M. Fraser, and J. C. Dunning Hotopp. (2016) Efficient Enrichment of Bacterial mRNA from Host-Bacteria Total RNA Samples. Scientific Reports, 5: 34850.
Xiong, Q., H. Bekebrede, P. Sharma, L. G. Arroyo, J. D. Baird, and Y. Rikihisa. (2016) An ecotype of Neorickettsia risticii causing Potomac Horse Fever in Canada. Appl. Environ. Microbiol. 82: 6030-6036.
Lai, T-H, M.E. Parraga, E. Alvarez, and Y. Rikihisa. (2016) Anaplasma platys Immunoblot Test Using Major Surface Antigens. Vector-Borne and Zoonotic Diseases. 16: 581-587.
Lin, M., H. Liu, Q. Xiong, H. Niu, Z. Cheng, A. Yamamoto, and Y. Rikihisa (2016) Ehrlichia secretes Etf-1 to induce autophagy and capture nutrients for its growth through RAB5 and class III phosphatidylinositol 3-kinase. Autophagy. 12: 1-22.
Greiman, S., Y. Rikihisa, J. Cain, J. Vaughan, and V. Tkach (2016) Germs within worms: Localization of Neorickettsia sp. within life cycle stages of digenean Plagiorchis elegans. Appl. Environ. Microbiol. 82: 2356-2362.
Ge, Y., H. Yin, Y. Rikihisa, W. Pan, and H. Yin. (2016) Molecular detection of tick- borne pathogens in Rickettsiales in goats and sheep from southeastern China. Vector- Borne and Zoonotic Dis. 16: 309-316.
Klionsky, D.J., ---H. Niu, Y. Rikihisa---- >50 others (2016) Guidelines for the Use and Interpretation of Assays for Monitoring Autophagy (3rd edition) Autophagy. 12: 1-222.
Mohan-Kumar, D., M. Lin, Q. Xiong, M. J. Webber, C. Kural, and Y. Rikihisa. (2015) EtpE Binding to DNase X Induces Ehrlichial Entry via CD147 and hnRNP-K Recruitment, Followed by Mobilization of N-WASP and Actin. mBio. 6: e01541-15.
Rikihisa, Y. (2015) Molecular Pathogenesis of Ehrlichia chaffeensis Infection. Ann. Rev. Microbiol. 69: 283-304.
Harasawa, R., H. Fujita, T. Kadosaka, S. Ando, and Y. Rikihisa (2015) Proposal for ‘Candidatus Mycoplasma haemomuris subsp. musculi’ in mice, and ‘Candidatus Mycoplasma haemomuris subsp. ratti’ in rats. Int. J. Syst. Evol. Microbiol. 65: 734-737.
Cheng, Z., M. Lin, and Y. Rikihisa (2014) Ehrlichia chaffeensis proliferation begins with NtrY/NtrX and PutA/GlnA upregulation and CtrA degradation induced by proline and glutamine. mBio. 5: e02141-14.
Niu, H. and Y. Rikihisa (2014) Investigating interference with apoptosis induction by bacterial proteins. Methods in Molecular Biology. Ed. David O’ Callaghan and Annette Vergunst. 1197: 169-184.
Mohan-Kumar, D., M. Yamaguchi, K. Miura, M. Lin, M. Los, J. F. Coy, and Y. Rikihisa (2013) Ehrlichia chaffeensis uses its surface protein EtpE to bind GPI-anchored protein DNase X and trigger entry into mammalian cells. PLoS Pathog. 9: e1003666
Wang, P., P. Dadhwal, Z. Cheng, M. R. Zianni, Y. Rikihisa, F. T. Liang, and X. Li (2013) Borrelia burgdorferi Oxidative Stress Regulator BosR Directly Represses Lipoproteins Primarily Expressed in the Tick during Mammalian Infection. Mol. Microbiol. 89: 1140-1153.
Niu, H., and Y. Rikihisa (2013) Ats-1, a novel bacterial molecule that links autophagy to bacterial nutrition. Autophagy, 9: 1-2.
Niu, H., Q. Xiong, A. Yamamoto, M. Hayashi-Nishino, and Y. Rikihisa (2012) Autophagosomes Induced by a Bacterial Beclin 1-binding Protein Facilitate Obligatory Intracellular Infection. Proc. Natl. Acad. Sci. 109:20800-20807.
Liu, H., W. Bao, M. Lin, H. Niu, and Y. Rikihisa (2012) Ehrlichia chaffeensis Type IV Secretion Effector ECH0825 is Translocated to Mitochondria, and Inhibits Apoptosis by upregulating Host MnSOD. Cell. Microbiol. 14: 1037-1050.
Rahman, M. A., J. Matsuo, Z. Cheng and Y. Rikihisa (2012) Penicillin-Binding Protein of Ehrlichia chaffeensis: Cytokine Induction Through MyD88-Dependent Pathway. J. Infect. Dis. 206: 110-116.
Xiong, Q. and Y. Rikihisa (2012) Subversion of NPC1 pathway of cholesterol transport by Anaplasma phagocytophilum. Cell. Microbiol. 14: 560-576.
Cheng, Z. K. Miura, V. L. Popov, Y. Kumagai and Y. Rikihisa (2011) Insights into the CtrA Regulon in Development of Stress-resistance in Obligatory Intracellular Pathogen Ehrlichia chaffeensis. Mol. Microbiol. 82: 1217-1234.
Miura, K., J. Matsuo, M. A. Rahman, Y. Kumagai, X. Li and Y. Rikihisa (2011) Ehrlichia chaffeensis Induces Monocyte Inflammatory Responses Through MyD88, ERK and NF-κB, but not through TRIF, IL-1R1/IL-18R1, or TLRs. Infect. Immun. 79: 4947-4956.
Kumagai, Y., J. Matsuo, Z. Cheng, Y. Hayakawa, and Y. Rikihisa (2011) c-di-GMP Signaling Regulates Intracellular Aggregation, Sessility, and Growth of Ehrlichia chaffeensis Infect. Immun. 79: 3905-3912.
Rikihisa, Y. (2011) Mechanisms of obligatory intracellular infection with Anaplasma phagocytophilum. Clin. Microbiol. Rev. 24: 469-489.
Gibson, K., G. Pastenkos, S. Moesta, and Y. Rikihisa (2011) Neorickettsia risticii surface-exposed proteins: Proteomics identification, recognition by naturally-infected horses and strain variations. Vet. Res. 42: 71.
Ge, Y. and Y. Rikihisa (2011) Subversion of host cell signalings by Orientia tsutsugamushi. Microbes Infect. 13: 638-648.
Xiong, Q and Y. Rikihisa (2011) The prenylation inhibitor manumycin A reduces the viability of Anaplasma phagocytophilum. J. Med. Microbiol. 60: 744-749.
Lai, T., N. G. Orellana, Y. Yuasa, and Y. Rikihisa (2011) Cloning of the Major OMP Expression Locus in Anaplasma platys and Seroreactivity of a Species-Specific Antigen. J. Bacteriol. 193: 2924–2930.
Lin, M., T. Kikuchi, H.M. Mottaz-Brewer, A. D. Norbeck, and Y. Rikihisa (2011) Global Proteomic Analysis of Two Tick-borne Emerging Zoonosis Agents: Anaplasma phagocytophilum and Ehrlichia chaffeensis. Front. Cell. Infect. Microbiol. 2:24.
Gibson, K, Y. Kumagai, and Y. Rikihisa (2010) Proteomic Analysis of N. sennetsu Surface-exposed Proteins and Porin Activity of the Major Surface Protein P51. J. Bacteriol. 192: 5898-5905.
Kumagai, Y, Matsuo, J., Y. Hayakawa, and Y. Rikihisa (2010) c-di-GMP Regulates Ehrlichia chaffeensis Surface Proteins and Intracellular Infection. J. Bacteriol. 192:4122-33.
Rikihisa, Y., M. Lin, and H., Niu (2010) Type IV Secretion in Obligatory Intracellular Bacterium, Anaplasma phagocytophilum. Cell. Microbiol. 12:1213-21.
Rikihisa, Y. (2010) Anaplasma phagocytophilum and Ehrlichia chaffeensis, subversive manipulaters of host cells. Nature Rev., Microbiol. 8: 328-339.
Rikihisa, Y. (2010) Editorial: Diagnosis of canine monocytic ehrlichiosis: Development of advanced techniques to combat a global disease. Vet, J. 14: 250–251
Niu, H., V. Kozjak-Pavlovic, T. Rudel, and Y. Rikihisa (2009) Anaplasma phagocytophilum Ats-1 is Imported into Host Cell Mitochondria and Interferes with Apoptosis Induction. PLoS Pathogens 6: e1000774.
Rikihisa, Y. and M. Lin. (2010) Ehrlichia/Anaplasma Type IV Secretion and Ank Proteins. Current Opinion Microbiol. 13: 59-66.
O’Connor, T. P., J. Saucier, D. Daniluk, B. A. Stillman, R. Krah, Y. Rikihisa, Q. Xiong, M.J. Yabsley, D.S. Adams, P. V.P. Diniz, E. B. Breitschwerdt, S. Gaunt, R. Chandrashekar. (2010) Evaluation of peptide- and recombinant protein-based assays for detection of anti-Ehrlichia ewingii antibodies in experimentally and naturally infected dogs. J. Am.Vet. Res. 71:1195-1200.
Rikihisa, Y. (2010) Molecular events involved in cellular invasion by ehrlichia and anaplasma. Vet. Parasitol. 167: 155-166.
Kawahara, K, T. Tajima, H. Torii, M. Yabutani, J. Ishii, M. Harasawa, E. Isogai and Y. Rikihisa (2009) Ehrlichia chaffeensis Infection of Sika Deer from Nara Park, Japan. Emerg. Infect. Dis. 15: 1991-1993.
Lin, M., C. Zhang, K. Gibson, and Y. Rikihisa (2009) Analysis of Complete Genome Sequence of Neorickettsia risticii: the Causative Agent of Potomac Horse Fever. Nuc. Acid Res. 37: 6076-6091.
Xiong, Q., M. Lin., and Y. Rikihisa (2009) Anaplasma phagocytophilum acquires cholesterol through low-density lipoprotein uptake pathway. PLoS Pathogens. 5:e1000329
Grieg, J., Y. Rikihisa, and M. Wellman (2009) Importance of the use of PCR in confirmation of Ehrlichia ewingii infection. Vet. Clin. Pathol. 38: 406-410.
Rikihisa, Y. M. Lin, H. Niu, and Z. Cheng (2009) Type IV Secretion System of Anaplasma phagocytophilum and Ehrlichia chaffeensis. Ed. by K.E. Hechemy and D. A. Raoult. Ann N Y Acad Sci. 1166: 106-111.
Miura. K. and Y. Rikihisa (2009) Liver microarray profiles associated with strain-specific Ehrlichia chaffeensis–induced hepatitis in mice. Infect. Immun. 77: 245-254.
Lai, T-H., Y. Kumagai, M. Hyodo, Y. Hayakawa, and Y. Rikihisa. (2009) Anaplasma phagocytophilum PleC histidine kinase and PleD diguanylate cyclase two-component system and role of cyclic di-GMP in host-cell infection. J. Bacteriol. 191: 693-700. Selected to be highlighted by a Commentary.
Bao, W.†, H. Kumagai†, M. Niu, Y. Yamaguchi, K. Miura, and Y. Rikihisa. (2009) Four VirB6 Paralogs and VirB9 are Expressed and Interact in Ehrlichia chaffeensis-containing vacuole. J. Bacterial. 191; 278-286. (†equally contributed)
Unver, A., Y. Rikihisa, M. Karaman, and H. Ozen. (2008) An acute severe ehrlichiosis in a dog experimentally infected with a new virulent strain of Ehrlichia canis. Clin Microbiol. Infect. Dis. 15 (Suppl.1) 1-3.
Delos Santos, J. R., M. Oglesbee M, Y. Rikihisa., R. W. Stich (2008) Pathologic Evidence of Ehrlichiosis in Calves Inoculated with Ehrlichia chaffeensis Animal Biodiversity and Emerging Diseases: Ann. N.Y. Acad. Sci. 1149: 103–106.
Schaefer, J. J., J. Kahn, G. R. Needham, Y. Rikihisa, S. A. Ewing and R. W. Stich. (2008) Antibiotic Clearance of Ehrlichia canis from Dogs Infected by Intravenous Inoculation of Carrier Blood. Animal Biodiversity and Emerging Diseases: Ann. N.Y. Acad. Sci. 1149: 263–269.
Mottaz-Brewer, Heather M., A. D. Norbeck, J. N. Adkins, N. P. Manes, C. K. Ansong, L. Shi, Y. Rikihisa, T. Kikuchi, S. W. Wong, R. D. Estep, F. Heffron, L. Pasa-Tolic, and R. D. Smith (2008) Optimization of proteomic sample preparation procedures for comprehensive protein characterization of pathogenic systems. J. Biomol. Tech. 19: 285-295.
Huang, H†., M. Lin†, X. Wang, T. Kikuchi, H. Mottaz, A. Norbeck, and Y. Rikihisa (2008) Proteomic Analysis of and Immune Responses to Ehrlichia chaffeensis Lipoproteins. Infect. Immun. 76: 3405-3414. (†equally contributed)
Gibson, K. E. andY. Rikihisa (2008) Molecular link of different stages of the trematode host of Neorickettsia risticii. Environ. Microbiol. 10: 2064-20
Kumagai, Y., H. Huang, and Y. Rikihisa (2008) Expression and Porin Activity of P28 and OMP-1F during intracellular Ehrlichia chaffeensis Development. J. Bacteriol. 190: 3597-3605.
Cheng, Z., X. Wang, and Y. Rikihisa (2008) Regulation of Type IV secretion apparatus genes during Ehrlichia chaffeensis intracellular development by a previously unidentified protein. J. Bacteriol. 190: 2096-2105.
Zhang, C., Q. Xiong, T. Kikuchi, and Y. Rikihisa (2008) Identification of 19 polymorphic major outer membrane protein genes and their immunogenic peptides in Ehrlichia ewingii for use in a serodiagnostic assay. Clin. Vaccine Immunol. 15: 402-411.
Xiong, Q., W. Bao, Y. Ge, and Y. Rikihisa (2008) Ehrlichia ewingii Infection Delays Spontaneous Neutrophil Apoptosis Through Stabilization of Mitochondria. J. Infect. Dis. 197:1110-1118.
Niu, H., M. Yamaguchi, and Y. Rikihisa (2008) Subversion of cellular autophagy by Anaplasma phagocytophilum. Cell. Microbiol., 10: 593-605.
Delos Santos, J..R., K. Boughan, W.G. Bremer, B. Rizzo B, J.J. Schaefer, Y. Rikihisa, G. R. Needham, L.A. Capitini, D. E. Anderson, M. Oglesbee M, S. A. Ewing, R. W. Stich (2007) Experimental infection of dairy calves with Ehrlichia chaffeensis. J Med Microbiol. 56:1660-1668.
Xiong, Q., X. Wang, and Y. Rikihisa. (2007) High-Cholesterol Diet Facilitates Anaplasma phagocytophilum Infection and Up-regulates MIP-2 and CXCR2 Expression in Apolipoprotein E-Deficient Mice. J. Infect. Dis. 195: 1497-1503.
Huang, H., X. Wang, T. Kikuchi, Y. Kumagai, and Y. Rikihisa. (2007) Porin Activity of Anaplasma phagocytophilum Outer Membrane Fraction and Purified P44. J. Bacteriol. 189: 1998-2006. [PMCID: PMC1855737]
Wang, X., Z. Cheng, C. Zhang, T. Kikuchi, and Y. Rikihisa (2007) Anaplasma phagocytophilum p44 mRNA expression is differentially regulated in mammalian and tick host cells: Involvement of the DNA binding protein ApxR. J. Bacteriol. 189:8651-8659.
Ge, Y. and Y. Rikihisa (2007) Identification of Novel Surface Proteins of Anaplasma phagocytophilum by Affinity Purification and Proteomics. J. Bacteriol. 189: 7819-7828.
Schaefer, J. J., J. Kahn, G. R. Needham, Y. Rikihisa, S. A. Ewing and R. W. Stich (2007) Antibiotic clearance of Ehrlichia canis from dogs infected by intravenous inoculation of carrier blood. Antimicrob. Agents Chemother., 51:3394-3396.
Lin, M., A. den Dulk-Ras, and P. J. J. Hooykaas, and Y. Rikihisa (2007) Anaplasma phagocytophilum AnkA Secreted by Type IV Secretion System is Tyrosine Phosphorylated by Abl-1 to Facilitate Infection. Cell. Microbiol. 9: 2644-2657.
Wang, X., T. Kikuchi, and Y. Rikihisa. (2007) Proteomic Identification of A Novel Anaplasma phagocytophilum DNA Binding Protein That Regulates A Putative Transcription Factor. J. Bacteriol. 189: 4880-4886.
Ge, Y. and Y. Rikihisa. (2007) Surface-exposed proteins of Ehrlichia chaffeensis. Infect. Immun. 75: 3833-3841.
Miura, K. and Y. Rikihisa (2007) Virulence potential of Ehrlichia chaffeensis strains of Distinct Genome Sequences. Infect. Immun. 75: 3604-3613.
Lin, M and Y. Rikihisa (2007) Degradation of p22phox and Inhibition of Superoxide Generation by Ehrlichia chaffeensis in Human Monocytes. Cell. Microbiol. 9:861-874.
Kumagai, Y. Cheng, Z., M, Lin, and Y. Rikihisa (2006) Biochemical Activities of Three Pairs of Ehrlichia chaffeensis Two-Component Regulatory System Involved in Inhibition of Lysosomal Fusion. Infect. Immun 74: 5014-5022.
Unver, A., H. Huang, and Y. Rikihisa,(2006)Cytokine Gene Expression by Peripheral Blood Leukocytes in Dogs Experimentally Infected with a New Virulent Strain of Ehrlichia canis. Ed. by K.E. Hechemy and D. A. Raoult. Ann N Y Acad Sci. 1078: 482-486.
Perez, M., M. Bodor, C. Zhang, Q. Xiong, and Y. Rikihisa (2006) Human Infection with Ehrlichia canis Accompanied By Clinical Signs In Venezuela. Ann N Y Acad Sci. 1078: 110-117.
Rikihisa, Y. (2006) New Findings on Members of the Family Anaplasmataceae of Veterinary Importance. Ann N Y Acad Sci. 1078:438-445.
Ge, Y and Y. Rikihisa (2006) Anaplasma phagocytophilum delays spontaneous human neutrophil apoptosis by modulation of multiple apoptotic pathways. Cell. Microbiol. 8: 1406-1416.
Cheng, Z., Y. Kumagai, M. Lin, C. Zhang, and Y. Rikihisa (2006) Intra-leukocyte expression of two-component systems in Ehrlichia chaffeensis and Anaplasma phagocytophilum and effects of the histidine kinase inhibitor closantel. Cell Microbiol. 8: 1241-1252.
Dunning Hotopp, J. M. Lin, R. Madupu, J. Crabtree, S. Angiuoli, J. Eisen, R. Sesahdri, Q. Ren, T. R. Utterback, S. Smith, M. Lewis,H. Khouri, C. Zhang, N. Hua, Q. Lin, N. Ohashi, N. Zhi, W. Nelson, L. M. Brinkac, R. J. Dodson, M. J. Rosovitz, J. Sundaram, S. C. Daugherty, T. Davidsen, A. Durkin, M. Gwinn, D. H. Haft, J. D. Selengut, S.A. Sullivan, N. Zafar, L. Zhou, F. Benahmed, H. Forberger, R. Halpin, S. Mulligan, J. Robinson,Y. Rikihisa, H. Tettelin (2006) Comparative Genomics of Emerging Human Ehrlichioisis Agents. PLoS Genetics. 2: e21 1-16.
Lin, Q. C. Zhang, and Y. Rikihisa (2006) Analysis of p44 recombination intermediate in Anaplasma phagocytophilum and in E. coli using plasmid encoding p44 expression and donor loci. Infect. Immun. 74: 2052-2062.
Rikihisa, Y. (2006) Ehrlichia subversion of host innate immune responses. Current Opinion Microbiol. 9: 95-101.
Huang, H., A. Unver, M. J. Perez, N. G. Orellana, and Y. Rikihisa (2006) Prevalence and molecular analysis of Anaplasma platys from dogs in Lara, Venezuela. Brazilian J. Microbiol. 36: 211-216.
Wang, X., T. Kikuchi, and Y. Rikihisa (2006) Two neutralization sites defined by epitope-mapping and monoclonal antibody inhibition analysis on P44 major surface proteins of Anaplasma phagocytophilum. Infect. Immun. 74: 1873-1882.
Perez, M., M. Bodor, C. Zhang,and Y. Rikihisa (2006) Human infection with Ehrlichia canis accompanied by Clinical Signs In Venezuela. Ann.New York Acad. Sci., in press.
Unver, A., H. Huang, and Y. Rikihisa,(2006)Cytokine Gene Expression by Peripheral Blood Leukocytes in Dogs Experimentally Infected with a New Virulent Strain of Ehrlichia canis. Ann. New York Acad. Sci., in press.
Rikihisa, Y. (2006) New Findings on Members of the Family Anaplasmataceae of Veterinary Importance. Ann. New York Acad. Sci., in press.
Kawahara, M, Y. Rikihisa, Q. Lin, E. Isogai, K. Tahara, A. Itagaki, Y. Hiramitsu, and T. Tajima. (2006) Genetic variants of Anaplasma phagocytophilum, Anaplasma bovis, Anaplasma centrale and Ehrlichia species in wild deer on two major islands in Japan. Appl. Env. Microbiol. 72: 1102-1109.
Niu, H, Y. Rikihisa, M. Yamaguchi, and N. Ohashi (2006) Differential Expression of VirB9 and VirB6 During Lifecycle of Anaplasma phagocytophilum in Human Leukocytes is Associated with Differential Binding and Avoidance of Lysosome Pathway. Cell Microbiol. 8: 523-534.
Tajima, T. and Y. Rikihisa. (2005) Cytokine responses in Ehrlichia canis-infected dogs. Ann. New York Acad. Sci., 1063:429-32.
Unver, A., Y. Rikihisa, K. Borku, Y. E. Ozkanlar, and B. Hanedan. (2005) Molecular detection and characterization of Ehrlichia canis from dogs in Turkey. Berl. Münch.Tierärztl.Wschr. 118, 300-304.
Bremer WG, Schaefer JJ, Wagner ER, Ewing SA, Rikihisa Y, Needham GR, Jittapalapong S, Moore DL, Stich RW. (2005) Transstadial and intrastadial experimental transmission of Ehrlichia canis by male Rhipicephalus sanguineus. Vet Parasitol. 131: 95-105.
Lin, Q. and Y. Rikihisa. (2005) Establishment of cloned Anaplasma phagocytophilum and analysis of p44 Gene conversion within infected horse and SCID mice. Infect. Immun. 73:5106-5114.
Gibson, K. E. Y. Rikihisa, C. Zhang, and C. Martin (2005) Neorickettsia risticii is vertically transmitted in the trematode Acanthatrium oregonense and horizontally transmitted to bats. Environ. Microbiol. 7: 203-212.
Ge, Y., K. Yoshiie, F. Kuribayashi, M. Lin and Y. Rikihisa (2005) Anaplasma phagocytophilum inhibits human neutrophil apoptosis via upregulation of bfl-1, maintenance of mitochondrial membrane potential, and prevention of caspase 3 activation. Cell. Microbiol. 7: 29-38.
Wang, X., Y. Rikihisa, T. Lai, Y. Kumagai, N. Zhi, and S. M. Reed (2005) Rapid sequential changeover of expressed p44 genes during the acute phase of Anaplasma phagocytophilum infection in horses. Infect. Immun. 72: 6852-6859.
Lin, Q., Y. Rikihisa. R. F. Massung, and Z. Woldehiwet (2004) Polymorphism and transcription at the p44-1/p44-18 genomic locus in Anaplasma phagocytophilum strains from diverse geographic regions. Infect. Immun. 72: 5574-5581.
Wang, X., Y. Rikihisa, T. Lai, Y. Kumagai, N. Zhi, and S. M. Reed (2004) Rapid sequential changeover of expressed p44 genes during the acute phase of Anaplasma phagocytophilum infection in horses. Infect. Immun. 72: 6852-6859.
Lin, Q., Y. Rikihisa. R. F. Massung, and Z. Woldehiwet (2004) Polymorphism and transcription at the p44-1/p44-18 genomic locus in Anaplasma phagocytophilum strains from diverse geographic regions. Infect. Immun. 72: 5574-5581.
Rikihisa, Y., C. Zhang, M. Kanter, Z. Cheng, N. Ohashi, and T. Fukuda (2004) Analysis of p51, groESL, and the major antigen P51 in various species of Neorickettsia, an obligatory intracellular bacterium of trematodes and mammals. J. Clin. Microbiol. 42: 3823-3826.
Kawahara, M., Y. Rikihisa, E. Isogai, M. Takahashi, H. Misumi, C. Suto, S. Shibata, C. Zhang and M. Tsuji. (2004) Ultrastructure and phylogenetic analysis of ‘Candidatus Neoehrlichia mikurensis’ in the family Anaplasmataceae isolated from wild rats and found in Ixodes ovatus ticks. Int. J. Syst. Evol. Microbiol. 54: 1837-1843.
Lin, Q., Y. Rikihisa, S.Felek, X. Wang, R. F. Massung, and Z. Woldehiwet. (2004) Anaplasma phagocytophilum has functional msp2 distinct from p44. Infect Immun. 72: 3883-3889.
Wagner, E., W.G. Bremer, Y. Rikihisa, S.A. Ewing, G.R. Needham, A. Unver, X. Wang, R.W. Stich. (2004) Development of a p28-based PCR assay for Ehrlichia chaffeensis. Mol. Cell Probes. 18:111-116.
Zhang, C., and Y. Rikihisa. (2004) Proposal to transfer ‘Aegyptianella ranarum’, an intracellular bacterium of frog red blood cells, to the family Flavobacteriaceae as ‘Candidatus Hemobacterium ranarum’ comb. nov. Environ. Microbiol. 6: 568-573.
Felek,S., S.Telford IIIrd, R. C. Falco, and Y. Rikihisa (2004) Sequence analysis of p44 homologs expressed by Anaplasma phagocytophilum in infected ticks feeding on naïve hosts and in mice infected by tick attachment. Infect. Immun. 72: 659-666.
Lin, M. and Y. Rikihisa (2004) Ehrlichia chaffeensis Down Regulates Surface Toll-like Receptors 2/4 and CD14 and Transcription Factors PU.1 in Host Monocytes Subsequent to Inhibition of p38 MAPK, ERK 1/2, and NF-kB Pathways. Cell. Microbiol. 6:175-186.
Lin, M. and Y. Rikihisa (2003) Obligate intracellular parasitism by human monocytic and granulocytic ehrlichiosis agents involves caveolae and glycosylphosphatidylinositol-anchored proteins. Cell. Microbiol. 5: 809-820.
Rikihisa, Y., C. Zhang, and B. M. Christensen. (2003) Molecular characterization of Aegyptianella pullorum (Rickettsiales, Anaplasmataceae). J. Clin. Microbiol. 41: 5294-5297.
Lin, Q., Y. Rikihisa, N. Ohashi, and N. Zhi (2003) Mechanisms of Variable p44 Expression by Anaplasma phagocytophilum. Infect. Immun. 71: 5650-5661.
Felek, S, H. Huang, and Y. Rikihisa (2003) Sequence and expression analysis of virB9 of the type IV secretion system of Ehrlichia canis strains in ticks, dogs, and cultured cells. Infect. Immun. 71: 6063-6067.
Lin, M. and Y. Rikihisa (2003) Ehrlichia chaffeensis and Anaplasma phagocytophilum lack genes for Lipid A biosynthesis and incorporate cholesterol for their survival. Infect. Immun. 71: 5324-5331.
Felek, S., R. Greene, and Y. Rikihisa. (2003) Transcriptional analysis of p30 major outer membrane protein genes of Ehrlichia canis in naturally infected ticks and sequence analysis of p30-10 of E. canis from diverse geographic regions. J. Clin. Microbiol. 41: 886-888.
Okada, H., H. Usuda, T.Tajima, M. Kawahara, T. Yoshino, and Y. Rikihisa. (2003) Detection and localization of Ehrlichia sp. HF strain most closely related to Ehrlichia chaffeensis in a mouse model by in situ hybridization. J. Comp. Pathol. 128: 182-187.
Rikihisa, Y. (2003) Mechanisms to create a safe haven by members of the family Anaplasmataceae. Ann. New York Acad. Sci., 990: 548-555.
Unver, A., Y. Rikihisa, M. Kawahara, and S. Yamamoto. (2003). Analysis of 16S rRNA Gene Sequences of Ehrlichia canis, Anaplasma platys, and Wolbachia Species from the Blood of Dogs in Japan. Ann. New York Acad. Sci., 990: 692-698.
Harasawa, Y., M. Kawahara, and Y. Rikihisa. (2002) Characteristics of the 16S-23S rRNA intergenic spacer region of Mycoplasma haemomuris, previously classified as Haemobartonella muris. J.Vet.Med.Sci. 64: 1161-1164.
Zhi, N., N. Ohashi, and Y. Rikihisa. (2002) Activation of a p44 pseudogene in Anaplasma phagocytophila by bacterial RNA splicing: A novel mechanism for posttranscriptional regulation of a multigene family encoding immunodominant major outer membrane proteins. Mol. Microbiol. 46:135-146.
Lin, Q. N. Zhi, N. Ohashi, H. W. Horowitz, M.E. Aguero-Rosenfeld, J. Ruffalli, G. P.Wormser, and Y. Rikihisa. (2002) Diverse p44 Gene expression by Anaplasma phagocytophila in acutely infected patients. J. Clin. Microbiol. 40: 2981-2988.
Kim, H-Y. J. Mott, N. Zhi, T. Tajima, Y. Rikihisa. (2002) Cytokine gene expression by peripheral blood leukocytes in horses during experimental infection with Anaplasma phagocytophila. Clin. Diag. Lab. Immunol. 9: 1079-1084.
Liddell, A.M., Sumner JW, Paddock CD, Rikihisa Y, Unver A, Buller RS, and Storch GA (2002) Reinfection with Ehrlichia chaffeensis in a Liver Transplant Recipient. Clin. Infect. Dis. 34: 1644-1647.
Unver, A., Y. Rikihisa, R.W. Stich, N. Ohashi, and S. Felek. (2002) The omp-1 Major Outer Membrane Multigene Family of Ehrlichia chaffeensis is Differentially Expressed in Canine and Tick Hosts. Infect. Immun. 70: 4701-4704.
Kim, Y-H, and Y. Rikihisa. (2002) Roles of p38 Mitogen-Activated Protein Kinase, NF-kB and Protein Kinase C in Proinflammatory Cytokine mRNA Expression by Human Peripheral Blood Leukocytes in Response to Anaplasma phagocytophila. Infect. Immun. 70: 4132-4141.
Zhang, C., and Y. Rikihisa. (2002) Evaluation of Sensitivity and Specificity of Mycoplasma haemomuris-Specific PCR. Comp. Med. 52: 204-206.
Neimark, H., K-E Johansson, Y. Rikihisa, and J. Tilly. (2002) Revision of haemotrophic Mycoplasma species names. Int. J. Syst. Evol. Microbiol. 52: 683.
Stich, R. W. Y.Rikihisa, S.A. Ewing, G.R. Needham, D. L. Grover and S. Jittapalapong (2002) Detection of Ehrlichia canis in Canine Carrier Blood and in Individual Experimentally Infected Ticks with a p30-Based PCR Assay . J. Clin.Microbiol. 40: 540-546.
Ohashi, N., N. Zhi, Q. Lin, and Y. Rikihisa. (2002) Characterization and Transcriptional Analysis of Gene Clusters for a Type IV Secretion Machinery in Human Granulocytic and Monocytic Ehrlichiosis Agents. Infect. Immun. 70: 2128-2138.
Zhi, N., N. Ohashi, T. Tajima, J. Mott, R. W. Stich, D. Grover, S. R. Telford III, Q. Lin, and Y. Rikihisa. (2002) Transcript Heterogeneity of p44 Multigene Family in Human Granulocytic Ehrlichiosis Agent Transmitted by Ticks. Infect. Immun. 70: 1175-1184.
Mott, J., Y. Rikihisa and S. Tsunawaki (2002) Effects of Anaplasma phagocytophila on NADPH Oxidase Components in Human Neutrophils and HL-60 cells. Infect. Immun. 70: 1359-1366.
Mott, J, Y. Muramatsu, E. Seaton, C. Martin, S. Reed, and Y. Rikihisa. (2002) Molecular Analysis of Ehrlichia risticii in Adult Aquatic Insects in Pennsylvania, in Horses Infected by Ingestion of Insects, and Isolated in Cell Culture. J. Clin. Microbiol. 40: 690-693.
Lin, M., M. X. Zhu, and Y. Rikihisa. (2002) Activation of PLC-g2, Increase in Cytosolic Free Calcium, Recruitment of PLC-g2 and Tyrosine Phosphorylated Proteins to Its Inclusion by Ehrlichia chaffeensis for Intracellular Growth in THP-1 Cells. Infect. Immun. 70: 889-898.
Dumler, J. S., A. F. Barbet, C. P. J. Bekker, G.A. Dasch, G. H. Palmer, S. C. Ray, Y. Rikihisa, and F.R. Rurangirwa (2001) Reorganization of Genera in the Families Rickettsiaceae and Anaplasmataceae in the order Rickettsiales; Unification of some species of Ehrlichia with Anaplasma, Cowdria with Ehrlichia, and Ehrlichia with Neorickettsia; Description of six New Species Combinaions; and Designation of Ehrlichia equi and "HGE agent" as Subjective Synonyms of Ehrlichia phagocytophila. Int. J. Syst. Evol. Microbiol. 51: 2145-2165.
Neimark, H., K-E Johansson, Y. Rikihisa, and J. Tilly. (2001) Proposal to transfer some members of the genera Haemobartonella and Eperythrozoon to the Genus Mycoplasma with descriptions of ‘Candidatus Mycoplasma hemofelis’, ‘Candidatus Mycoplasma hemomuris’, ‘Candidatus Mycoplasma hemosuis’ and ‘Candidatus Mycoplasma wenyonii’. Int. J. Syst. Evol. Microbiol. 51: 891-899.
Okada, H., T. Tajima, M. Kawahara, and Y. Rikihisa. (2001) Ehrlichial proliferation in endothelial cells and lethal liver necrosis in immunocompetent mice experimentally infected with HF strain most closely related to Ehrlichia chaffeensis. J. Comp. Pathol. 124: 165-171.
Felek, S., A. Unver, R.W. Stich, and Y. Rikihisa. (2001) Sensitive detection of Ehrlichia chaffeensis in cultured cells, blood, and ticks by RT-PCR. J. Clin. Microbiol. 39: 460-463.
Ohashi, N., Y. Rikihisa, and A. Unver. (2001) Analysis of transcriptionally active gene clusters of major outer membrane protein multigene family in Ehrlichia canis and E. chaffeensis. Infect. Immun. 69: 2083-2091.
Unver, A., Felek, S., N. Zhi, C. Paddock, H. W. Horowitz, G. P.Wormser, and Y. Rikihisa. (2001) Western Immunoblot Analysis of HME and HGE dual reactive sera. J. Clin. Microbiol. 39: 3982-3986.
Unver, A., M., N. Ohashi, T. Tajima, R.W. Stich, D. Grover, and Y. Rikihisa (2001). Transcriptional Analysis of p30 Major Outer Membrane Multigene Family of Ehrlichia canis in Dogs, Ticks, and Cell Culture at Different Temperatures. Infect. Immun. 69: 6172-6178.
Unver, A., M. Perez,N..Orellana, H. Huang, and Y. Rikihisa. (2001) Molecular and antigenic comparison of Ehrlichia canis from dogs, ticks, and a human in Venezuela. J. Clin. Microbiol. 39: 2788-2793.
Yoshiie, K., Kim, Y-H, Mott, J., and Y. Rikihisa (2000) Intracellular infection by human granulocytic ehrlichiosis agent inhibits human neutrophil apoptosis. Infect. Immun. 68: 1125-1133.
Mott, J., and Y. Rikihisa. (2000) Human granulocytic ehrlichiosis agent inhibits superoxide anion generation by human neutrophils. Infect. Immun. 68: 6697-6703.
Walker, D.H., J. Bakken, P. Brouqui, J. Childs, L. Cullman, J. Dawson, J.S. Dumler, V. Fingerle, J. Goodman, P. Hogan, W. Hogrefe, J. Liz, L.A. Magnarelli, J. Markley, R. Massung, E.J. Masters, C. Murphy, J. Olano, C. Padoock, M. Petrovec, Y. Rikihisa, S. Standaert, G. P. Wormser, X-Y. Yu, T.A. Zupanic. (2000) Consensus on Diagnosis of Human Ehrlichioses. ASM News. 66: 287-290. (authors are listed in alphabetical order except for Walker, D.H. the organizer)
Kanter, M., J. Mott, N. Ohashi, B. Fried, S. Reed, Y. Lin, and Y. Rikihisa. (2000) Analysis of 16S rRNA and 51-kDa antigen gene and transmission in mice of Ehrlichia risticii in virgulate trematodes from Elimia livescens snails in Ohio. J. Clin. Microbiol. 38: 3349-3358.
Rikihisa, Y. (2000) Diagnosis of Emerging Ehrlichial Diseases of Dogs, Horses, and Humans. Editorial. J. Vet. Int. Med. 14: 250-251.
Tajima, T., N. Zhi, Q. Lin, Y. Rikihisa, H.W. Horowitz, J. Ralfalli, G.P. Womser, and K. Hechemy. (2000) Enzyme-linked immunosorbent assay using major outer membrane protein of the human granulocytic ehrlichiosis agent. Clin. Diag. Lab. Immunol. 7: 652-657.
Sumner, J.W., G.A. Storch, R.AS. Buller, A.M. Liddell, S.L. Stockham, Y.Rikihisa, S. Messenger, J.E. Childs, and C.D. Paddock. (2000) PCR amplification and phylogeneticc analysis of groESL operon sequences from Ehrlichia ewingii and Ehrlichia muris. J. Clin. Microbiol. 38: 2746-2749.
Kim, Y-H, and Y. Rikihisa. (2000) Expression of interleukin-1β, tumor necrosis factor-α, and IL-6 in human peripheral blood leukocytes exposed to viable human granulocytic ehrlichiosis agent or recombinant major surface antigen P44. Infect. Immun. 68: 3394-3402.
Shibata, S., M. Kawahara, Y. Rikihisa, H. Fujita, Y. Watanabe, C. Suto, and T.Ito (2000) New Ehrlichia sp. closely related with E. chaffeensis isolated from Ixodes ovatus ticks in Japan. J. Clin. Microbiol. 38: 1331-1338.
Buller, R.S., M. Arens, S. P. Hmiel, C. Paddock, J.W. Sumner, Y. Rikihisa, A. Unver, M. Graudreauls-Keener, F. A. Marinian, A. M. Liddell, N. Schmulewitz, and G. Storch. (1999) Ehrlichia ewingii, a newly recognized agent of human ehrlichiosis. New Engl. J. Med. 341: 148-155.
Zhi, N., N. Ohashi, and Y. Rikihisa. (1999) mRNA expression of the multigene family encoding 44-kDa major outer membrane proteins of the human granulocytic ehrlichiosis agent. J. Biol. Chem. 274:17828-17836.
Barnewall, R., N. Ohashi, and Y. Rikihisa (1999) Ehrlichia chaffeensis and E. sennetsu, but not the Human granulocytic ehrlichiosis agent colocalize with transferrin receptor and up-regulate transferrin receptor mRNA by activating iron-responsive protein 1. Infect Immun. 67: 2258-2265.
Mott, J., R. Barnewall, and Y. Rikihisa. (1999) Human granulocytic ehrlichiosis agent and Ehrlichia chaffeensis reside in different cytoplasmic compartments in HL-60 cells. Infect. Immun. 67: 1368-1378.
Kawahara, M., T. Ito, C. Suto, S. Shibata, Y. Rikihisa, K. Hara, and K. Hirai. (1999) Comparison of Ehrlichia muris isolated from wild mice and ticks, and serologic evidence of human and animal exposure to E. muris. J. Clin.Microbiol. 37: 1123-1129.
Unver, A., Y. Rikihisa, N. Ohashi, L.C. Cullman, R. Buller, and G.A. Storch. (1999) Western and dot blotting analysis of Ehrlichia chaffeensis IFA-positive and negative sera using native and recombinant E. chaffeensis and E. canis antigen. J. Clin. Microbiol. 37: 3888-3895.
Rikihisa, Y. (1999) Clinical and biological aspects of infections caused by Ehrlichia chaffeensis. Microb. Infect. 1: 367-376.
Ohashi, N., N. Zhi, Y. Zhang, and Y. Rikihisa. (1998) Immunodominant major outer membrane proteins of Ehrlichia chaffeensis are encoded by a polymorphic multigene family. Infect. Immun. 66:132-139.
Barlough, J.E., G.H. Reubel, J.E. Madigan, L.K. Vredevoe, P.E. Miller, and Y. Rikihisa. (1998) Detection of Ehrlichia risticii, the agent of Potomac horse fever, in freshwater stream snails (Pleuroceridae: Juga spp.) of Northern California. J. Appl. Environ. Microbiol. 64: 2888-2893.
Zhi, N., N. Ohashi, Y. Rikihisa, H.W. Horowitz, G.P. Womser, K. Hechemy. (1998) Cloning and expression of 44-kDa major outer membrane protein antigen gene of human granulocytic ehrlichiosis agent and application of the recombinant protein to serodiagnosis. J. Clin. Microbiol. 36: 1666-1673.
Zhang, Y., N. Ohashi, and Y. Rikihisa. (1998) Cloning of the heat shock protein 70 (HSP70) of Ehrlichia sennetsu and differential expression of HSP70 and HSP60 mRNA after temperature upshift. Infect. Immun. 66: 3106-3112.
Horowitz, H.W., M.E. Aguero-Rosenfeld, D.F. McKenna, D. Holmgren, T-Z. Hsieh, S. A. Varde, S.J. Dumler, J. M. Wu, I. Schwartz, Y. Rikihisa, and G. P. Wormser. (1998) Clinical and laboratory spectrum of culture-proven human granulocytic ehrlichiosis: Comparison with cculture-negative cases. Clin. Infect. Dis. 27: 1314-1317.
Lee, E. and Y. Rikihisa. (1998) Protein kinase A-mediated inhibition of interferon-gamma-induced tyrosine phosphorylation of Janus kinases and latent cytoplasmic transcription factors in human monocytes by Ehrlichia chaffeensis. Infect. Immun. 66: 2514-2520.
Kim, Y-H, and Y. Rikihisa. (1998) Characterization of monoclonal antibodies against the major outer membrane protein of human granulocytic ehrlichiosis agent. J. Clin. Microbiol. 36: 3278-3284.
Ohashi, N., Unver, A., and Y. Rikihisa. (1998) Cloning and characterization of multigenes encoding immunodominant 30-kDa major outer membrane protein of Ehrlichia canis and application of the recombinant protein for serodiagnosis. J. Clin. Microbiol. 36:2671-2680.
Rikihisa, Y., N. Zhi, G. Wormser, B. Wen, H.W. Horowitz, and K.E. Hechemy. (1997) Ultrastructural and Antigenic Characterization of a Granulocytic Ehrlichiosis Agent Directly Isolated and Stably Cultivated from a Patient in New York State J. Infect. Dis. 175: 210-213.
Barlough, J.E., Y. Rikihisa, and J.E. Madigan. (1997) Nested polymerase chain reaction for detection of Ehrlichia risticii genomic DNA in infected horses. Vet. Parasitol. 68: 367-373.
Zhang, Y., N. Ohashi, E. Lee, and Y. Rikhisa. (1997) Ehrlichia sennetsu groE operon and antigenic properties of the groEL homolog. FEMS Immunol. Med. Microbiol. 18: 39-46.
Rikihisa, Y., M. Kawahara, B. Wen, G. Kociba, P. Fuerst, F. Kawamori, C. Suto, S. Shiba, and M. Futohashi. (1997) Western immunoblot analysis of Haemobartonella muris and comparison of 16SrDNA sequences of H. muris, H. felis, and Eperythrozoon suis. J. Clin. Microbiol. 35: 823-829.
Barnewall, R.E., Y. Rikihisa, and E.H. Lee. (1997) Ehrlichia chaffeensis inclusions are early endosomes which selectively accumulate transferrin receptor. Infect. Immun. 65: 1455-1461.
Mott, J.,Y. Rikihisa, Y. Zhang, S. M. Reed, C.Y. Yu.. (1997) Polymerase chain reaction and Southern blot analysis of E. risticii in the blood and feces of horses. J. Clin. Microbiol. 35: 2215-2219.
Lee, E. and Y. Rikihisa. (1997) Anti-Erhlichia chaffeensis antibody induces potent proinflammatory cytokine mRNA expression in human monocytes exposed to E. chaffeensis through sustained reduction of IkB-α and activation of NF-kB. Infect. Immun. 65: 2890-2897.
Zhang, Y. and Y. Rikihisa. (1997) Tyrosine phosphorylation is required for ehrlichial internalization and replication in P388D1 cells. Infect. Immun. 65: 2959-2964.
Wen, B., Y. Rikihisa, N. Zhi, R. Greene, and R. Bartsch. (1997) Nested polymerase chain reaction for detection of Ehrlichia canis infection in dogs. J. Clin. Microbiol. 35: 1852-1855.
Zhi, N., Y. Rikihisa, H.Y. Kim, G.P. Wormser, and H.W. Horowitz. (1997) Comparison of major antigenic proteins of six strains of human granulocytic ehrlichiosis agents by Western immnoblot analysis. J. Clin. Microbiol. 35: 2606-2611.
Madigan, J.E., J.E. Barlough, Y. Rikihisa, B. Wen, P.E. Miller, and T.J. Sampson. (1996) Identification of the "Shasta River Crud" syndrome as Potomac horse fever (Equine monocytic ehrlichiosis). J. Equine Vet. Sci. 17: 270-272.
Wen, B., Y. Rikihisa, S. Yamamoto, and P. Fuerst. (1996) Characterization of SF agent, an Ehrlichia sp. isolated from Stellantchasmus falcatus fluke, by 16S rRNA base sequence, serological, and morphological analysis. Int. J. Syst. Bacteriol. 46, 149-154.
Kawahara, M., C. Suto, S. Shibata,M. Futohashi, and Y. Rikihisa. (1996) Impaired antigen specific responses and enhanced polyclonal stimulation in mice infected with Ehrlichia muris. Microbiol. Immunol. 40:575-581.
Lee, E. and Y. Rikihisa. (1996) Absence of TNF-α, IL-6, and GM-CSF but presence of IL-1β, IL-8, and IL-10 expression in human monocytes exposed to viable or killed Ehrlichia chaffeensis. Infect. Immun. 64:4211-4219.
Perez, M., Y. Rikihisa, and B. Wen. (1996) Antigenic and genetic characterization of an Ehrlichia canis-like agent isolated from a human in Venezuela. J. Clin. Microbiol. 34:2133-2139.
Rikihisa, Y., Y. Zhang, and J. Park (1995) Role of Ca2+ and calmodulin on ehrlichial survival in macrophages. Infect. Immun. 63, 2310-2316.
Rikihisa, Y. (1995) Ehrlichial Diseases. In Zoonotic Diseases. Clin. Microbiol. 22, 413-419 (In Japanese).
Wen, B., Y. Rikihisa, J. Mott, P.A. Fuerst, and M. Kawahara. (1995) Ehrlichia muris sp. nov., a new species of Ehrlichia, identified on the basis of 16SrRNA base sequence, serological, morphological, and biological characteristics. Int. J. Syst. Bacteriol. 45, 250-254.
Pretzman, C., D. Ralph, D. Stotherd, P. Fuerst, and Y. Rikihisa. (1995) 16SrRNA sequence relatedness of Neorickettsia helminthoeca to Ehrlichia risticii and Ehrlichia sennetsu. Int. J. Syst. Bacteriol. 45, 207-211.
Wen, B., Y. Rikihisa, P.A. Fuerst, and W. Chaichanasiriwithaya. (1995) Analysis of 16SrRNA genes of ehrlichial organisms isolated from horses with clinical signs of Potomac horse fever. Int. J. Syst. Bacteriol. 45, 315-318.
Madigan, J.E., Y. Rikihisa, J. Palmer, E. DeRock, and J. Mott. (1995) Evidence for a high rate of false positive results with the indirect fluorescent antibody test for Ehrlichia risticii antibody in horses. Am. J. Vet. Med. Assoc. 207, 1448-1453.
Yamamoto, S., S. Miyaji, K. Otabe, K. Mukawa, E. Momotani, and Y. Rikihisa. (1994) Preparation of anti-canine serum amyloid (SAA) serum and purification of SAA from canine high density lipoprotein. Vet. Immunol. Immunopathol. 41, 41-53.
Yamamoto, S., S. Miyaji, Y. Ashida, Y. Nishimura, H. Niizeki, and Y. Rikihisa. (1994) Serosurvey of anti-Ehrlichia canis antibody in dogs. J. Japanese Small Animal Veterinary Med. Assoc. 47, 765-767. (In Japanese).
Rikihisa, Y., S. Yamamoto, I. Kwak, Z. Iqbal, J. Mott, and G. Kociba. (1994) Plasma C reactive protein and α1-acid glycoprotein concentrations in dogs infected with Ehrlichia canis. J. Clin. Microbiol. 32, 912-917.
Rikihisa, Y., S.A. Ewing, and J.C. Fox. (1994) Western immunoblot analysis of Ehrlichia chaffeensis, E. canis, or E. ewingii infection of dogs and human. J. Clin. Microbiol. 32, 2107-2112.
Iqbal, Z., and Y. Rikihisa. (1994) Reisolation of Ehrlichia canis from blood and tissues of dogs after treatment with doxycycline. J. Clin. Microbiol. 32, 1644-1649.
Messick, J.B. and Y. Rikihisa. (1994) Inhibition of binding, entry or survival of Ehrlichia risticii in P388D1 cells by anti-E. risticii IgG and Fab fragments. Infect. Immun. 62, 3156-3161.
Iqbal, Z., W. Chaichanasiriwithaya, and Y. Rikihisa. (1994) Comparison of PCR and Western immunoblot analysis in early diagnosis of canine ehrlichiosis. J. Clin. Microbiol. 32, 1658-1662.
Iqbal, Z. and Y. Rikihisa. (1994) Application of polymerase chain reaction for detection of Ehrlichia canis in tissues of dogs. Vet. Microbiol. 42, 281-287.
Barnewall, R. and Y. Rikihisa. (1994) Abrogation of interferon-γ induced inhibition of Ehrlichia chaffeensis infection in human monocytes with iron transferin. Infect. Immun. 62, 4804-4810.
Lin, Y.C., A. Sambuissho, S. Coskun, Y. Rikihisa. (1994) Inhibition of in vitro fertilization and early embryogenic development in hamsters by gossypol. Life. Sci. 55, 1139-1145.
Chaichanasiriwithaya, W., Y. Rikihisa, S. Yamamoto, S.M. Reed, L.E. Perryman, T.B. Crawford, and G. Palmer. (1994) Antigenic, morphologic, and molecular characterization of 9 new Ehrlichia risticii isolates. J. Clin. Microbiol. 38, 3026-3033.
Rikihisa, Y., Y. Zhang, and J. Park. (1994) Role of clathrin, microfilament, and microtubule on infection of mouse peritoneal macrophages with Ehrlichia risticii. Infect. Immun. 62, 5126-5132.
Yamamoto, S., T. Shida, K. Otabe, E. Furukawa, Y. Isayama, and Y. Rikihisa. (1994) Serum C-reactive protein and immune responses in dogs inoculated with Bordetella bronchiseptica (phase I cells). Vet. Res. Commun. 18, 347-357.
Rikihisa, Y., R. Wada, S.M. Reed, and S. Yamamoto. (1993) Development of neutralizing antibodies in horses infected with Ehrlichia risticii. Vet. Microbiol. 36, 139-147.
Kawahara, M., C. Suto, and Y. Rikihisa. (1993) Characterization of Ehrlichial organisms isolated from a wild mouse. J. Clin. Microbiol. 31, 89-96.
Kulp, S.K., Y. Rikihisa, Y.C. Lin, P.P. Moh, P.K. Li, and Y. Gu. (1993) In vitro uptake and autoradiographic localization of 3H-gossypol in Taenia taeniaeformis metacestode. Parasitol. Res. 79, 279-285.
Messick, J.B. and Y. Rikihisa. (1993) Characterization of Ehrlichia risticii binding, internalization, and growth in host cells by flow cytometry. Infect. Immun. 61, 3803-3810.
van Heeckeren, A., Y. Rikihisa, J. Park, and R. Fertel. (1993) Tumor necrosis factor-α, Interleukin-1β, Interleukin-6 and prostaglandin E2 production in murine peritoneal macrophages infected with Ehrlichia risticii. Infect. Immun. 61, 4333-4337.
Messick, J.B. and Y. Rikihisa. (1992) Suppression of I-Ad on P388D1 cells by Ehrlichia risticii infection in response to gamma interferon. Vet. Immunol. Immunopathol. 32, 225-241.
Rikihisa, Y., G.J. Johnson, Y.-Z. Wang, S.M. Reed, R. Fertel, and H.J. Cooke. (1992) Loss of adsorptive capacity for sodium chloride as a cause of diarrhea in Potomac horse fever. Res. Vet. Sci. 52, 353-362.
Riond, J.-L., J.E. Riviere, W.M. Duckett, C.E. Atkins, A.D. Jernigan, Y. Rikihisa, and S.L. Spurlock. (1992) Cardiovascular effects and fatalities associated with intravenous administration of doxycycline to horses. Equine Vet. J. 24, 41-45.
Rikihisa, Y., S.A. Ewing, J.C. Fox, A.G. Siregar, F.H. Pasaribu, and M.B. Malole. (1992) Enzyme-linked immunosorbent assay and western immunoblot analysis of E. canis and canine granulocytic Ehrlichia. J. Clin. Microbiol. 30, 143-148.
Budiarso, I.T. and Y. Rikihisa. (1992) Pulmonary vascular lesions in Jembrana disease. Vet. Pathol. 29, 210-215.
Messick, J.B. and Y. Rikihisa. (1992) Presence of parasite antigens on the surface of P388D1 cells infected with Ehrlichia risticii. Infect. Immun. 60, 3079-3086.
Park, J. and Y. Rikihisa. (1992) L-arginine-dependent killing of intracellular Ehrlichia risticii by macrophages treated with interferon-gamma. Infect. Immun. 60, 3504-3508.
Chen, C.J.A., Y.C. Lin, R.W. Brueggemeier, and Y. Rikihisa. (1992) Morphometric analysis renal cortex changes induced by diethylstilbestrol (DES) in syrian hamsters. Research Communications in Chemical Pathology and Pharmacology. 78, 341-358.
Kiper, M.L., Traub-Dargtz, J., Salman, M.D., and Y. Rikihisa. (1992) Risk factors for equine monocytic ehrlichiosis seropositivity in horses in Colorado. Preventive Medicine 13, 251-259.
Lin, Y.C., P. Rajamahendran and Y. Rikihisa (1991) Inhibition of rat embryo implantation in the gossypol-treated uterine horn. Theriogenology. 35, 769-777.
Dawson, J.E., Y. Rikihisa, S. Ewing and D.B. Fishbein (1991) Serologic diagnosis of human ehrlichiosis using two Ehrlichia canis isolates. J. Infect. Dis. 163, 564-567.
Coskun, S., A. Sunbuissho, Y.C. Lin and Y. Rikihisa (1991) Fertilizability and subsequent developmental ability of bovine oocyte matured in medium containing epidermal growth factor (EGF). Theriogenology. 36, 485-494.
Gu, Y., P.K. Li, Y.C. Lin, Y. Rikihisa and R.W. Brueggemeier (1991) Gossypolone suppresses progesterone synthesis in cultured bovine luteal cells. J. Steroid Biochem. Mol. Biol. 38, 709-715.
Rikihisa, Y. (1991) Protection against murine Potomac horse fever by an inactivated Ehrlichia risticii vaccine. Vet. Microbiol. 28: 339-350.
Rikihisa, Y., H. Stills, and G. Zimmerman. (1991) Isolation and continuous culture of Neorickettsia helminthoeca in a macrophage cell line. J. Clin. Microbiol. 29, 1928-1933.
Park, J. and Y. Rikihisa. (1991) Inhibition of Ehrlichia risticii growth in murine peritoneal macrophage by gamma interferon, calcium ionophore, and concanavalin A. Infect. Immun. 59, 3418-3423.
Rikihisa, Y. (1991) Cross-reacting antigens between Neorickettsia helminthoeca and Ehrlichia spp. shown by immunofluorescence and Western immunoblotting. J. Clin. Microbiol. 29, 2024-2029.
Rikihisa, Y. (1991) The tribe Ehrlichieae and ehrlichial diseases. Clin. Microbiol. Rev. 4:286-308.
Lin, Y.C., Y. Gu, R.W. Brueggemeier, and Y. Rikihisa. (1991) Binding of 3H-gossypol in organelles in cultured bovine luteal cells. Life Sci 50, 443-447.
Lin, Y.C., M. Chitcharoenthum, Y. Rikihisa and F.C. Gwazdauska (1990) Effect of gossypol on thyroid hormones in young female rats. Contraception 41, 431-440.
Gu, Y., .G. Chang, Y. Rikihisa and Y.C. Lin (1990) Inhibitory effect of gossypol on human chorionic hormone (hCG)-induced progesterone secretion in cultured bovine luteal cells. Life Sciences. 47, 407-414.
Lin, Y.C., Y. Rikihisa, H. Kono, and Y. Gu (1990) Effect of larval tapeworm (Taenia taeniaeformis) infection on reproductive functions in male and female host rats. Exp. Parasitol. 70, 344-352.
Rikihisa, Y., Y.C. Lin, P.L. Garber, and Y. Gu (1990) Taenia taeniaeformis: Inactivation of metacestode by gossypol in vitro. Exp. Parasitol. 71, 135-145.
Rikihisa, Y., S.M. Reed, R.A. Sams, J.C. Gordon and C.I. Pretzman (1990) Serosurvey of horses with evidence of equine monocytic ehrlichiosis (Potomac horse fever). J. Am. Vet. Med. Assoc. 197, 1327-1332.
Gu. Y, Y.C. Lin, and Y. Rikihisa (1990). Inhibitory effect of gossypol on steroidogenic pathways in cultured bovine luteal cells. Biochem. Biophys. Res. Commun. 169, 455-461.
Rikihisa, Y. (1990) Growth of Ehrlichia risticii in human colonic epithelial cells. In: Rickettsiology: Current issues and perspectives. New York Acad. Sci. 590, 104-110.
Rikihisa, Y. and Y.C. Lin (1989) Effect of gossypol on the thyroid in young rats. J. Comp. Pathol. 100, 411-417.
Lin, Y.C., R. Rajamahendran, Y. Rikihisa and F.C. Gwazdauskas (1989) Effect of gossypol and its metabolite on in vitro early development of mouse embryos. Theriogenology 31, 727-740.
Rikihisa, Y. and B.M. Jiang (1989) Effect of antibiotics on clinical, gross pathologic, and immunologic responses of mice infected with Ehrlichia risticii; Protective effects of doxycycline. Vet. Microbiol. 19, 253-262.
August, J.R., W.R. Chickering and Y. Rikihisa (1988) Congenital ichthyosis in a dog: Comparison with the human ichthyosiform dermatoses. Compendium of Continuing Education 10, 40-45.
Rikihisa, Y. and Y.C. Lin (1988) Ultrastructural changes in testes and epididymides of Japanese quail (Coturnix coturnix japonica) after gossypol treatment. Poult. Sci., 67, 961-972.
Lin, Y.C., T. Dietrick and Y. Rikihisa (1988) Antifertility effect of gossypol in male Japanese quail (Coturnix coturnix japonica). Life Sci. 42, 2283-2292.
Rikihisa, Y. and B.M. Jiang (1988) In vitro susceptibility of Ehrlichia risticii to eight antibiotics. Antimicrobial Agents & Chemotherapy 32, 986-991.
Wells, M.Y. and Y. Rikihisa (1988) Lack of lysosomal fusion with phagosomes containing Ehrlichia risticii in P388D1 cells: Abrogation of inhibition with oxytetracycline. Infect. Immun. 56, 3209-3215.
Rikihisa, Y., C.I. Pretzman, G.C. Johnson, S.M. Reed, S. Yamamoto and F. Andrews (1988) Clinical and immunological responses of ponies to Ehrlichia sennetsu and subsequent Ehrlichia risticii challenge. Infect. Immun. 56, 2960-2966.
Lin, Y.C., M. Chitcharoenthum and Y. Rikihisa (1987) Effect of gossypol on spermatozoal lactate dehydrogenase‑X (LDH‑X) in male rats. Contraception, 36, 581‑592.
Lin, Y.C. and Y. Rikihisa (1987) Antiandrogenic activity of gossypol metabolites in young male rats. In: "Cell Biology of the Testis and Epididymis." Ann. New York Acad. Sci.. 83‑85.
Pretzman, C.I., Y. Rikihisa and D. Ralph (1987) Enzyme‑linked immunosorbent assay for detecting Potomac horse fever disease. J. Clin. Microbiol. 25, 31‑36.
Rikihisa, Y., G.J. Johnson and C.J. Burger (1987) Reduced immune responsiveness and lymphoid depletion in mice infected with Ehrlichia risticii. Infect. Immun. 55, 2215‑2222.
Rikihisa, Y., Y.C. Lin and A. Walton (1986) Taenia taeniaeformis: Immunoperoxidase localization of metacestode culture product(s) in hyperplastic gastric mucosa. Exp. Parasitol. 61, 134‑137.
Perry, B.D., J.E.Palmer, H.F. Troutt, J.B. Birch, D. Morris and Y. Rikihisa (1986) A case‑control study of Potomac horse fever. Prev. Vet. Med. 4, 69‑82.
Cordes, D.O., B.D. Perry, Y. Rikihisa and W.R. Chickering (1986) Enterocolitis caused by Ehrlichia sp. in the horse (Potomac horse fever). Vet. Pathol. 23, 471‑477.
Steele, K., Y. Rikihisa and A. Walton (1986) Demonstration of Ehrlichia in Potomac horse fever using a silver stain. Vet. Pathol. 23, 531‑533.
Burger, C.J., Y. Rikihisa and Y.C. Lin (1986) Taenia taeniaeformis inhibition of mitogen‑induced proliferation and interleukin 2 production in rat splenocytes by larval in vitro product. Exp. Parasitol. 62, 216‑222.
Rikihisa, Y. and Y.C. Lin (1986) Taenia taeniaeformis: Inhibition of metacestode development in the rat by gossypol. Exp. Parasitol. 61, 127‑133.
Lin, Y.C., T. Fukaya, Y. Rikihisa and A. Walton (1985) Gossypol in female fertility control: ovum implantation and early pregnancy inhibited in rats. Life Science 37, 39‑47.
Blohowiak, C.C., T.L. De Santo, Y. Rikihisa and Y.C. Lin (1985) Diurnal, premating and postmating testosterone levels in chickens genetically selected for mating frequency. Poultry Sci. 64, 1028‑1030.
August, J.R., A.S. Loar, G.K. Saunders and Y. Rikihisa (1985) Membranous glomerular nephropathy and nephrotic syndrome in a cat. Compendium of Continuing Education 7, 363‑368.
Rikihisa, Y. and Y.C. Lin (1985) Taenia taeniaeformis: Inhibition of testosterone production by culture excretory‑secretory product of larvae. Exp. Parasitol. 59, 390‑397.
Rikihisa, Y. and B.D. Perry (1985) Causative ehrlichial organisms in Potomac Horse Fever. Infect. Immun. 49, 513‑517.
King, C.S., Y.C. Lin, T. Fukaya and Y. Rikihisa (1985) In vivo and in vitro inhibition of HCG‑induced testosterone production in rat testes by bursa of fabricius extract. Poultry Sci. 64, 1223‑1226.
Lin, Y.C., T. Fukaya, Y. Rikihisa and T. DeSanto (1985) Inhibitory effect of gossypol on human chorionic gonadotropin induced testosterone secretion in young male rats. Adv. Contraceptive Deliv. Syst. 200‑207.
Rikihisa, Y. (1985) Ultrastructural localization of carbonic anhydrase in lysosomes. Anat. Rec. 211, 1‑8.
Rikihisa, Y., B.D. Perry and D.O. Cordes (1985) Ultrastructural study of rickettsial organisms in the large colon of ponies experimentally infected with Potomac Horse Fever. Infect. Immun. 49, 505‑512.
Lin, Y.C., T. Fukaya and Y. Rikihisa (1985) Age related human chorionic gonadotropin responsiveness for testosterone production in young male rats. Life Science 37, 481‑488.
Rikihisa, Y., Y.C. Lin and A. Walton (1985) Histopathologic changes of uterus in gossypol‑treated early‑pregnant rat. Anat. Rec. 213, 72‑76.
Perry, B.D., Y. Rikihisa and G. Saunders (1985) Transmission of Potomac Horse Fever by intradermal route. Vet. Rec. 116, 246‑247.
Hammerberg, C., M. Hollingshead, Y. Rikihisa and R.DeBuysscher (1985) Porcine lymphoblastoid cell lines of B‑cell origin. Vet. Immunol. Immunopathol. 10, 367‑380.
Rikihisa, Y. (1984) Glycogen autophagosomes in polymorphonuclear leukocytes induced by rickettsiae. Anat. Rec. 208, 319‑327.
Rikihisa, Y. and Y.C. Lin (1984) Taenia taeniaeformis: Increased cell growth and neutral mucus production in the gastric mucosa of the rat infected with the larvae. Exp. Parasitol. 58, 147‑155.
Rikihisa, Y., T. Letonja, N. Pratt and Y.C. Lin (1984) Taenia taeniaeformis: Characterization of larval metabolic product and growth of host gastric cells in vitro. Exp. Parasitol. 58, 230‑238.
Hammerberg, B., Y. Rikihisa and M.W. King (1984) Immunoglobulin interactions with surfaces of sheathed and unsheathed microfilariae. Parasite Immunol. 6, 421‑434.
Rikihisa, Y., B.D. Perry and D. Cordes (1984) Rickettsial link with acute equine diarrhea. Vet. Rec. 115, 390.
Rikihisa, Y. and B.D. Perry (1984) Causative agent of Potomac Horse Fever. Vet. Rec. 115, 554.
Letonja, T., Rikihisa, Y. and C. Hammerberg (1984) Differential cellular response of resistant and susceptible rodents to the early stage of infection of Taenia taeniaeformis. Intl. J. Parasitol. 14, 551‑558.
Rikihisa, Y. and S. Ito (1983) Effect of antibody on entry of Rickettsia tsutsugamushi into polymorphonuclear leukocytes. Infect. Immun. 39, 928‑938.
Rikihisa, Y. and S. Ito (1982) Mechanism of entry of Rickettsia tsutsugamushi into polymorphonuclear leukocytes. Infect. Immun. 38, 343‑350.
Rikihisa, Y. and S. Ito (1980) Localization of electron dense tracers during entry of Rickettsia tsutsugamushi into polymorphonuclear leukocytes. Infect. Immun. 30, 231‑242.
Onitsuka, M., Y. Rikihisa and H.B. Maruyama (1979) Biochemical and topological studies on Escherichia coli cell surface IV. Giant spheroplast formation from filamentous cell. J. Bacteriol. 138, 567‑574.
Rikihisa, Y., T.R. Rota, A.B. MacDonald and S. Ito (1979) Changes in immunoferritin labeling of Rickettsia tsutsugamushi after serial cultivation in 60Co‑irradiated BHK cells. Infect. Immun. 26, 638‑650.
Rikihisa, Y. and S. Ito (1979) Intracellular localization of R. tsutsugamushi in polymorphonuclear leukocytes. J. Exp. Med. 150, 703‑708.
Rikihisa, Y. and D. Mizuno (1978) Different perturbations of phagolysosome membranes depending on the particles phagocytized: Observations with markers of the two sides of plasma membrane. Exp. Cell Res. 111, 437‑449.
Rikihisa, Y. and D. Mizuno (1977) Demonstration of myosin on the cytoplasmic side of plasma membrane of guinea pig polymorphonuclear leukocytes. Exp. Cell Res. 110, 87‑92.
Rikihisa, Y. and D. Mizuno (1977) Binding of markers of either side of plasma membranes to the cytoplasmic side of paraffin oil‑loaded phagolysosomes. Exp. Cell Res. 110, 93‑102.
Rikihisa, Y. and D. Mizuno (1977) Binding of markers of either side of plasma membranes to the cytoplasmic side of lysosomes. Exp. Cell Res. 110, 103‑110.
Rikihisa, Y., S. Ohkuma and D. Mizuno (1976) Improved immunoferritin technique to remove nonspecific binding. Cell Structure and Function 1, 251‑258.
Rikihisa, Y., S. Ohkuma and D. Mizuno (1976) Antigenic difference between the outer and inner surfaces of plasma membranes of polymorphonuclear leukocytes shown with immunoferritin. Exp. Cell Res. 100, 23‑30.

Book Chapters

Rikihisa, Y. (2019) Salmon poisoning disease and Elokomin fluke fever. In: Merck Veterinary Manual. Veterinary professionals, Generalized Conditions, Rickettsial Diseases. [http://www.merckmanuals.com/vet/generalized_conditions/ rickettsial_diseases/salmon_poisoning_disease_and_elokomin_fluke_fever.html]
Rikihisa, Y. (2017) The family Anaplasmataceae. In: Pathogenic bacteria, Virus. Ed. Hiroshi Oda, Hokkaido University Press. (In Japanese). PP. 120-124.
Thomas, S., W. Alexander, J. Gilligan, and Y. Rikihisa. (2016) Importance of Rickettsiales infections. In: Rickettsiales. Biology, Molecular Biology, Epidemiology, and Vaccine Development. Ed. Sunil Thomas. Springer International Publishing AG Switzerland. PP.3-22.
Niu, H. and Y. Rikihisa (2016) Chapter 8. Intracellular Bacterium Anaplasma phagocytophilum Induces Autophagy by Secreting Substrate Ats-1 that neutralizes the Beclin 1-ATG14L Autophagy Initiation Pathway. In: AUTOPHAGY: Cancer, Other Pathologies, Inflammation, Immunity, Infection, and Aging. Ed. M. A. Hayat. Elsevier Publishing Company Amsterdam, Netherlands. volume 9 Human Diseases and Autophagosome: PP 308-314.
Rikihisa, Y. (2015) Salmon poisoning disease and Elokomin fluke fever. In: Merck Veterinary Manual. Veterinary professionals, Generalized Conditions, Rickettsial Diseases. [http://www.merckmanuals.com/vet/generalized_conditions/ rickettsial_diseases/salmon_poisoning_disease_and_elokomin_fluke_fever.html]
Rikihisa, Y. (2009) Ehrlichia, Anaplasma. In: Intracellular Niches of Pathogens—A microbe’s Guide through the host cell. Ed. Ulrich E. Schaible and Albert Haas. Wiley-VCH Publishers. pp. 301-314.
Hechemy, K.E. and Y. Rikihisa (2007) Rickettsiology: Present and Future. In: Contemporary State of The Rickettsioses in the World and in Bulgaria. Ed. By Emil Alexandrov. pp. 17-26.
Hechemy, K.E. Y. Rikihisa, K. Macaluso, A. W. O. Burgess, B. E. Anderson, and H. A. Thompson. (2006) The Rickettsiaceae, Anaplasmataceae, Bartonellaceae, and Coxiellaceae. In 7th ed. Manual of Clinical Laboratory Immunology. American Society for Microbiology Press, Washington, D.C. pp. 526-539.
Dumler, J.S., Y. Rikihisa, and G.A. Dasch. Anaplasmataceae. In Brenner, Krieg, Staley and Garrity (Editors), The Proteobacteria, Part C, Bergey's Manual of Systematic Bacteriology, 2nd. Ed., Vol. 2, Springer, New York, NY (2005), p. 117.
Dumler, J.S., Y. Rikihisa, and G.A. Dasch. Anaplasma. In Brenner, Krieg, Staley and Garrity (Editors), The Proteobacteria, Part C, Bergey's Manual of Systematic Bacteriology, 2nd. Ed., Vol. 2, Springer, New York, NY (2005), pp. 117-125.
Dumler, J.S., Y. Rikihisa, and G.A. Dasch. Ehrlicihia. In Brenner, Krieg, Staley and Garrity (Editors), The Proteobacteria, Part C, Bergey's Manual of Systematic Bacteriology, 2nd. Ed., Vol. 2, Springer, New York, NY (2005), pp. 125-131
Rikihisa, Y. J.S. Dumler and G.A. Dasch. Neorickettsia. In Brenner, Krieg, Staley and Garrity (Editors), The Proteobacteria, Part C, Bergey's Manual of Systematic Bacteriology, 2nd. Ed., Vol. 2, Springer, New York, NY (2005), pp. 132-137
Rikihisa, Y. and J.P. Kreier. Aegyptianella. In Brenner, Krieg, Staley and Garrity (Editors), The Proteobacteria, Part C, Bergey's Manual of Systematic Bacteriology, 2nd. Ed., Vol. 2, Springer, New York, NY (2005), pp. 143-145.
Rikihisa, Y. (2004) Rickettsial diseases. In: Equine Internal Medicine. 2nd Edition. Ed. by S.M. Reed,W. Bayly and D.C. Sellon eds. W.B. Saunders. PP. 96-109.
Waites, K. B., Y. Rikihisa, and D. Taylor-Robinson (2003) Mycoplasma and Ureaplasma. .In Manual of Clinical Microbiology, 8th Edition. Ed., by P.A. Murray. American Society for Microbiology, Washington, D.C. PP. 972-990
Hechemy, K.E. and Y. Rikihisa. (2002) Immunoserology of Rickettsiales, Bartonella, and Coxiella. In 6th ed. Manual of Clinical Laboratory Immunology. Ed., by N.R. Rose, R.G. Hamilton, B. Detrick. ASM Press, Wasington, D.C. pp.528-541.
Rikihisa, Y. (2000) Ehrlichial strategy for survival and proliferation in the leukocytes. In: Subcellular Biochemistry: Bacterial invasion into eukaryotic cells. eds. J. Hacker and T. Olschlger. Plenum Publishing Co. 33: 517-538.
Rikihisa, Y. (2000) Analysis of pathogenesis of human ehrlichiosis, In: Eds. By T. Kurata and F. Amano. Latent Pathogen, 5: Saikon publishing Co., Tokyo (In Japanese). PP. 197-212.
Rikihisa, Y. (1999) Ehrlichiae of Veterinary Importance. In: Rickettsiae and Rickettsial Diseases at the Turn of the Third Millenium. Eds. by D. Raoult and P. Brouqui. Elsevior, Paris. 393-405.
Rikihisa, Y. (1997) Rickettsial diseases in horses. In Equine Internal Medicine. Ed. by W. Bayly and S.M. Reed. eds. W.B. Saunders. 112-123.
Rikihisa, Y. (1996) Ehrlichiae. In: Rickettsiae and Rickettsial Diseases (Bratislava, Slovak Republic). Slovak Academy of Sciences, Bratislava, Slovak Republic: International Society of Rickettsiae and Rickettsial Diseases, pp 272-286.
Rikihisa, Y. and G. Zimmerman. (1995) Salmon poisoning disease. In Current Veterinary Therapy XII Small Animal Practice Ed. by Kirk and Bonagura. P. 297-300. W.B. Saunders Co., Philadelphia.
Rikihisa, Y. (1995) Chapter 1. Classification and Morphology of Bacteria and Fungi. In: Essentials of Veterinary Bacteriology, Mycology, and Virology by G.R. Carter, Lee and Febiger, Philadelphia, P. 3-15.
Rikihisa, Y. (1990) Ultrastructure of rickettsiae with special emphasis on ehrlichia. In: Ehrlichiosis: A vector-borne Disease of Animals and Humans. In Current Topics in Veterinary Medicine and Animal Sciences, 54, p. 22-31. Ed. by J.C. Williams and I. Kakoma, Kluwer Publishing Co., Norwell, MA.
Rikihisa, Y. (1986) Chapter 1. Classification and Morphology of bacteria and fungi. In: Essentials of Veterinary Bacteriology and Mycology by G.R. Carter, Lea and Febiger, Philadelphia, pp 3‑15.
Rikihisa, Y. (1986) Ultrastructural studies of ehrlichial organisms in the organs of ponies with equine monocytic ehrlichiosis (synonym, Potomac horse fever). In H. Winkler and M. Ristic eds. Microbiology 1986 American Society for Microbiology, Washington, D.C., pp. 200‑202.
Rikihisa, Y. and S. Ito (1981) Outer membrane vesicles of Rickettsia tsutsugamushi in baby hamster kidney cells. In: Rickettsiae and Rickettsial Diseases. Eds. Willy Burgdorfer and Robert L. Anacker. Academic Press, pp. 229‑240.
Ito, S. and Y. Rikihisa (1981) Techniques for electron microscopy of rickettsiae. In: Rickettsiae and Rickettsial Diseases. Eds. Willy Burgdorfer and Robert L. Anacker. Academic Press, pp. 213‑227.

Proceedings

Kawahara, M and Y. Rikihisa. (2002) Ehrlichiosis in Japanese Society for Microbiology (in Japanese) website (http://wwwsoc.nii.ac.jp/jsb/topix/ehrlichia/INDEX.HTM).
Rikihisa, Y. (1997) Ehrlichiae, emerging human pathogens. In: Proceedings of the 2nd International Symposium on Lyme Disease. Shizuoka, Japan, pp.332-345.
Rikihisa, Y., W. Chaichanasiriwithaya, S.M. Reed, and S. Yamamoto. (1995) Distinct antigenic differences of new Ehrlichia risticii isolates. In: Proc. 7th International Conferences on Equine Infectious Diseases. 1994, Tokyo, Japan. R&W Publishing, Newmarket, U.K. P. 211-215.
Rikihisa, Y. and J. Park (1991) Ehrlichiacidal mechansism by macrophage Ca2+ mobilization. In J. Kazân and D. Raoult, eds., Proc. IVth International Symposium Rickettsiae and Rickettsial diseases. Pub. Slovak Acad. Sci., Blatislava, Czechoslovakia, P. 758-761.
Rikihisa, Y., G.C. Johnson and S.M. Reed (1988) Immune responses and intestinal pathology of ponies experimentally infected with Potomac horse fever. In: Proc. Symposium on Potomac Horse Fever. Veterinary Learning systems, Lawrenceville, NJ. 27‑31.
Rikihisa, Y., S.M. Reed, R. Sams, J. Gordon and K. Korn (1988) Serological survey and clinical management of horses with Potomac horse fever. In: Proc. Symposium on Potomac Horse Fever. Veterinary Learning Systems, Lawrenceville, NJ. 41‑47.
Whitlock, R.H., B. Perry, A. Jenny, J. Palmer, M. Ristic, E. Schmidtmann, C. Holland, J. Sessions, M. Robb, Y. Rikihisa, C. Benson, S. Dutta and R. Meinersmann (1986) Potomac horse fever: Update and research priorities. Proceedings of the 89th Annual Meeting of the United States Animal Health Association, Milwaukee, Wisconsin. pp 23‑29.
Rikihisa, Y. and L.L. Logan (1986) Unusual peptidoglycan substance in Cowdria ruminantium in the endothelial cells of the choroid plexus of the goat. Proc. XIth Int. Cong. on Electron Microscopy. pp. 3345‑3346.
Whitlock, R.H., B. Perry, A. Jenny, J. Palmer, M. Ristic, E. Schmidtmann, C. Holland, J. Sessions, M. Robb, Y. Rikihisa, C. Benson, S. Dutta and R. Meinersmann (1986) Potomac horse fever: Update and research priorities. Proceedings of the 89th Annual Meeting of the United States Animal Health Association, Milwaukee, Wisconsin. pp 23‑29.
Rikihisa, Y., S.M. Reed and R.A. Sams (1986) Potomac horse fever. Ohio Thoroughbred. Sep/Oct. pp. 34‑37.
Rikihisa, Y., L. Fainter and Y.C. Lin (1985) X‑ray microanalysis of metacestode hooks and calcareous corpuscles. Proceedings of Electron Microscopy Society of America. 518‑519.
Rikihisa, Y., and Y.C. Lin (1984) Tufts of modified microvilli of tapeworm inserted into liver tissue. Proceedings Electron Microscopy Society of America, pp. 318‑319.

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Yasuko Rikihisa

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