Faculty bio page2
Tetsuro Ikegami, PhD

Tetsuro Ikegami, PhDAssociate Professor

Department of Pathology
Member, The Sealy Center for Vaccine Development
Member, The Center for Biodefense and Emerging Infectious Diseases
Member, Center for Tropical Diseases
Phone: (409) 772-2563

Tetsuro Ikegami, PhD

Rift Valley fever is a mosquito-borne zoonotic disease (ruminants and humans) endemic to Africa. Rift Valley fever virus (RVFV) is a segmented negative-stranded RNA virus, which belongs to the genus Phlebovirus of family Bunyaviridae. RVFV is classified as Category A Priority Pathogen by NIH/NIAID, and an overlap select agent by CDC and USDA. Vaccination is an efficient strategy to prevent RVFV spread. Our laboratory undertakes a basic research to understand the safety and efficacy of the live-attenuated MP-12 vaccine and the recombinant variants. Using reverse genetics, we identified attenuation mutations for MP-12 vaccine. We also characterized the efficacy of recombinant MP-12 lacking NSs gene for DIVA (differentiation of infectious from vaccinated animals) purpose. More recently, we identified temperature-sensitive mutations for MP-12 vaccine, and characterized the genetic stability of key mutations for MP-12 vaccine. As a part of vaccine development project, we also analyze the basic aspect of reassortant and recombination between RVFV and other buyaviruses. Using high containment facilities at UTMB, we generated several pathogenic RVFV strains by reverse genetics. We plan to study vaccine efficacy, viral pathogenesis, and host-virus interaction with established resource and environment.
BVSc (DVM equivalent) Azabu University, Kanagawa, Japan Veterinary Medicine 1999
PhD University of Tokyo, Tokyo, Japan Virology 2003
Post-Doctoral Fellow The University of Texas Medical Branch at Galveston, TX Virology 2008
2006-2008 The James W. McLaughlin postdoctoral fellowship. The University of Texas Medical Branch.
2009-2012 Career Development Award, Western Regional Center for Biodefense and Emerging Infectious Diseases Research, NIH/NIAID
1996-Present Japanese Society of Veterinary Science
1999-Present Japanese Society for Virology
2005-Present American Society for Virology
2008-Present American Society for Microbiology
2008-Present Member, Sealy Center for Vaccine Development, UTMB
2010-Present Member, Center for Biodefense and Emerging Infectious Diseases, UTMB
2011-Present Member, Center for Tropical Diseases, UTMB
2011-Present Academic Editor, PLoS ONE
2013-Present Associate Editor, Virology Journal
2013-Present Editorial Board Member, BioMed research International (Virology)
2015-Present Editorial Board Member (Review Editor), Frontier Microbiology (Virology)
  1. Ikegami T, Peters CJ, Makino S. Rift valley fever virus nonstructural protein NSs promotes viral RNA replication and transcription in a minigenome system. J Virol. 2005;79(9):5606-15. Epub 2005/04/14. doi: 79/9/5606 [pii] 10.1128/JVI.79.9.5606-5615.2005. PubMed PMID: 15827175; PMCID: 1082746.
  2. Ikegami T, Won S, Peters CJ, Makino S. Rift Valley fever virus NSs mRNA is transcribed from an incoming anti-viral-sense S RNA segment. J Virol. 2005;79(18):12106-11. Epub 2005/09/06. doi: 79/18/12106 [pii] 10.1128/JVI.79.18.12106-12111.2005. PubMed PMID: 16140788; PMCID: 1212623.
  3. Ikegami T, Won S, Peters CJ, Makino S. Rescue of infectious rift valley fever virus entirely from cDNA, analysis of virus lacking the NSs gene, and expression of a foreign gene. J Virol. 2006;80(6):2933-40. Epub 2006/02/28. doi: 80/6/2933 [pii] 10.1128/JVI.80.6.2933-2940.2006. PubMed PMID: 16501102; PMCID: 1395455.
  4. Won S, Ikegami T, Peters CJ, Makino S. NSm and 78-kilodalton proteins of Rift Valley fever virus are nonessential for viral replication in cell culture. J Virol. 2006;80(16):8274-8. Epub 2006/07/29. doi: 80/16/8274 [pii] 10.1128/JVI.00476-06. PubMed PMID: 16873285; PMCID: 1563821.
  5. Ikegami T, Won S, Peters CJ, Makino S. Characterization of Rift Valley fever virus transcriptional terminations. J Virol. 2007;81(16):8421-38. Epub 2007/06/01. doi: JVI.02641-06 [pii] 10.1128/JVI.02641-06. PubMed PMID: 17537856; PMCID: 1951372.
  6. Ikegami T, Makino S. Rift valley fever vaccines. Vaccine. 2009;27 Suppl 4:D69-72. Epub 2009/10/20. doi: S0264-410X(09)01054-8 [pii] 10.1016/j.vaccine.2009.07.046. PubMed PMID: 19837291; PMCID: 2764559.
  7. Ikegami T, Narayanan K, Won S, Kamitani W, Peters CJ, Makino S. Rift Valley fever virus NSs protein promotes post-transcriptional downregulation of protein kinase PKR and inhibits eIF2alpha phosphorylation. PLoS Pathog. 2009;5(2):e1000287. Epub 2009/02/07. doi: 10.1371/journal.ppat.1000287. PubMed PMID: 19197350; PMCID: 2629125.
  8. Ikegami T, Makino S. The Pathogenesis of Rift Valley Fever. Viruses. 2011;3(5):493-519. Epub 2011/06/15. doi: 10.3390/v3050493. PubMed PMID: 21666766; PMCID: 3111045.
  9. Kalveram B, Lihoradova O, Ikegami T. NSs Protein of Rift Valley Fever Virus Promotes Post-Translational Downregulation of the TFIIH Subunit p62. J Virol. 2011;85:6234-43. Epub 2011/05/06. doi: JVI.02255-10 [pii] 10.1128/JVI.02255-10. PubMed PMID: 21543505.
  10. Head JA, Kalveram B, Ikegami T. Functional analysis of Rift Valley fever virus NSs encoding a partial truncation. PLoS ONE. 2012;7:e45730.
  11. Ikegami T. Molecular biology and genetic diversity of Rift Valley fever virus. Antiviral Res. 2012;95(3):293-310. Epub 2012/06/20. doi: S0166-3542(12)00142-8 [pii] 10.1016/j.antiviral.2012.06.001. PubMed PMID: 22710362.
  12. Indran SV, Ikegami T. Novel approaches to develop Rift Valley fever vaccines. Front Cell Infect Microbiol. 2012;2:131. Epub 2012/11/01. doi: 10.3389/fcimb.2012.00131. PubMed PMID: 23112960; PMCID: 3481114.
  13. Lihoradova O, Kalveram B, Indran SV, Lokugamage N, Juelich TL, Hill TE, Tseng CT, Gong B, Fukushi S, Morikawa S, Freiberg AN, Ikegami T. The dominant-negative inhibition of double-stranded RNA-dependent protein kinase PKR increases the efficacy of Rift Valley fever virus MP-12 vaccine. J Virol. 2012;86(14):7650-61. Epub 2012/05/11. doi: JVI.00778-12 [pii] 10.1128/JVI.00778-12. PubMed PMID: 22573861; PMCID: 3416293.
  14. Lokugamage N, Freiberg AN, Morrill JC, Ikegami T. Genetic Subpopulations of Rift Valley Fever ZH548, MP-12 and Recombinant MP-12 Strains. J Virol. 2012;86:13566-75. Epub 2012/10/05. doi: JVI.02081-12 [pii] 10.1128/JVI.02081-12. PubMed PMID: 23035230.
  15. Gowen BB, Bailey KW, Scharton D, Vest Z, Westover JB, Skirpstunas R, Ikegami T. Post-exposure vaccination with MP-12 lacking NSs protects mice against lethal Rift Valley fever virus challenge. Antiviral Res. 2013;98(2):135-43. Epub 2013/03/26. doi: S0166-3542(13)00063-6 [pii] 10.1016/j.antiviral.2013.03.009. PubMed PMID: 23523764.
  16. Indran SV, Lihoradova OA, Phoenix I, Lokugamage N, Kalveram B, Head JA, Tigabu B, Smith JK, Zhang L, Juelich TL, Gong B, Freiberg AN, Ikegami T. Rift Valley fever virus MP-12 vaccine encoding Toscana virus NSs retains neuroinvasiveness in mice. J Gen Virol. 2013;94(Pt 7):1441-50. Epub 2013/03/22. doi: vir.0.051250-0 [pii] 10.1099/vir.0.051250-0. PubMed PMID: 23515022; PMCID: 3709633.
  17. Kalveram B, Ikegami T. Toscana Virus NSs Protein Promotes Degradation of Double-Stranded RNA-Dependent Protein Kinase. J Virol. 2013;87:3710-8. Epub 2013/01/18. doi: JVI.02506-12 [pii] 10.1128/JVI.02506-12. PubMed PMID: 23325696.
  18. Kalveram B, Lihoradova O, Indran SV, Lokugamage N, Head JA, Ikegami T. Rift Valley fever virus NSs inhibits host transcription independently of the degradation of dsRNA-dependent protein kinase PKR. Virology. 2013;435:415-24. Epub 2012/10/16. doi: S0042-6822(12)00472-2 [pii] 10.1016/j.virol.2012.09.031. PubMed PMID: 23063407.
  19. Lihoradova OA, Indran SV, Kalveram B, Lokugamage N, Head JA, Gong B, Tigabu B, Juelich TL, Freiberg AN, Ikegami T. Characterization of Rift Valley Fever Virus MP-12 Strain Encoding NSs of Punta Toro Virus or Sandfly Fever Sicilian Virus. PLoS Negl Trop Dis. 2013;7(4):e2181. Epub 2013/05/03. doi: 10.1371/journal.pntd.0002181 PNTD-D-12-01435 [pii]. PubMed PMID: 23638202; PMCID: 3630143.
  20. Ikegami T, Hill TE, Smith JK, Zhang L, Juelich TL, Gong B, Slack OA, Ly HJ, Lokugamage N, Freiberg AN. Rift Valley Fever Virus MP-12 Vaccine Is Fully Attenuated by a Combination of Partial Attenuations in the S, M, and L Segments. J Virol.89(14):7262-76. Epub 2015/05/08. doi: JVI.00135-15 [pii] 10.1128/JVI.00135-15. PubMed PMID: 25948740; PMCID: 4473576

NIH Biosketch