Michael A. Matthias, PhD
George Palade Laboratories, Room 105
Michael A. Matthias, Ph.D., graduated from the University of the West Indies (UWI) with double first class honors in Biology and Chemistry in 1995, and was awarded the UWI Postgraduate Award that same year that funded his postgraduate work in Molecular and Medical Microbiology. He joined the UCSD Faculty as a member of the UCSD School of Medicine, Department of Medicine, Division of Infectious Diseases as Assistant Adjunct Professor of Medicine in 2009 with a research focus in Tropical Infectious Diseases.
Our research seeks to understand how microbial ecology and human genetics influence the transmission and clinical progression of leptospirosis using field and laboratory based studies that utilize molecular biology, biochemistry, immunology, cell biology, high throughput sequencing, metagenomics and comparative genomics approaches. Leptospirosis is perhaps the most widespread zoonotic disease worldwide with case fatality rates of 5 – 15%. The disease has gained recent attention as an emerging infectious disease due to flood-associated epidemics of severe pulmonary hemorrhage syndrome—a serious and often-fatal manifestation of leptospirosis—now recognized as a widespread and significant public health problem. Despite an improved understanding of leptospiral biology, there has been comparatively little progress made towards implementing effective public health responses and challenges with respect to diagnosis and clinical management persist globally. One of the important questions we are addressing is why some patients with leptospirosis develop mild “flu-like” illness, while others progress to acute renal failure, pulmonary hemorrhage, meningitis and/or myocarditis/heart failure. Our work at UCSD uses animal models to study the pathophysiology and immunopathogenesis of severe disease, while our studies in Iquitos include human and microbial ecology studies to gain mechanistic insights into the maintenance and transmission of leptospirosis, and are being done with collaborators at UCSD, the Universidad Peruana Cayetano Heredia, the J. Craig Venter Institute and Johns Hopkins University.
Klimpel GR, Matthias MA, Vinetz JM. Leptospira interrogans activation of human peripheral blood mononuclear cells: preferential expansion of TCR γδ+ T cells vs TCR αβ+ T cells. J Immunol. 2003 Aug 1; 171(3): 1447-55
Segura ER, Ganoza CA, Campos K, Ricaldi JN, Torres S, Silva H, Céspedes MJ, Matthias MA, Swancutt MA, López Liñán R, Gotuzzo E, Guerra H, Gilman RH, Vinetz JM; Peru-United States Leptospirosis Consortium. Clinical spectrum of pulmonary involvement in leptospirosis in a region of endemicity, with quantification of leptospiral burden. Clin Infect Dis. 2005 Feb 1; 40(3): 343-51. Epub 2005 Jan 10.
Matthias MA, Díaz MM, Campos KJ, Calderon M, Willig MR, Pacheco V, Gotuzzo E, Gilman RH, Vinetz JM. Diversity of bat-associated Leptospira in the Peruvian Amazon inferred by Bayesian Phylogenetic analysis of 16S ribosomal DNA sequences. Am J Trop Med Hyg. 2005 Nov; 73(5): 964-74
Viriyakosol S, Matthias MA, Swancutt MA, Kirkland TN, Vinetz JM. Toll-like receptor 4 protects against lethal Leptospira interrogans serovar Icterohaemorrhagiae infection and contributes to in vivo control of leptospiral burden. Infect Immun. 2006 Feb; 74(2): 887-95.
Ganoza CA, Matthias MA, Collins-Richards D, Brouwer KC, Cunningham CB, Segura ER, Gilman RH, Gotuzzo E, Vinetz JM. Determining risk for severe leptospirosis by molecular analysis of environmental surface waters for pathogenic Leptospira. PLoS Med. 2006 Aug; 3(8): e308
Barry M, Wisnewski AV, Matthias MA, Inouye SK, Vinetz JM. Suburban leptospirosis: atypical lymphocytosis and γδ-T cell response. Clin Infect Dis. 2006 Nov 15; 43(10): 1304-7. Epub 2006 Oct 16.
Matthias MA, Ricaldi JN, Cespedes M, Diaz MM, Galloway RL, Saito M,Steigerwalt AG, Patra KP, Ore CV, Gotuzzo E, Gilman RH, Levett PN, Vinetz JM. Human leptospirosis caused by a new, antigenically unique Leptospira associated with a Rattus species reservoir in the peruvian Amazon. PLoS Negl Trop Dis. 2008 Apr 2; 2(4): e213
Ganoza CA, Matthias MA, Saito M, Gotuzzo E and Vinetz, JM. A Cross-sectional Study of Human Asymptomatic Urinary Shedding of Leptospira in a Hyperendemic Region of the Peruvian Amazon. PLoS Negl Trop Dis. 2010 Feb 23; 4(2): e612
Agampodi SB, Matthias MA, Moreno AC and Vinetz JM. Utility of Quantitative PCR in Leptospirosis Diagnosis: Association of Level of Leptospiremia and Clinical Manifestations in Sri Lanka. CID. 2012; 54(9): 1249–55.
Ricaldi JN, Matthias MA, Vinetz JM and Lewis AL. Expression of sialic acids and other nonulosonic acids in Leptospira. BMC Microbiol. 2012 Aug 1; 12: 161.
Ricaldi, JN, Fouts DE, Selengut JD, Harkins DM, Moreno A, Lehmann JS, Patra KP, Purushe J, Sanka R, Torres M, Webster NJ, Vinetz JM and Matthias MA. Whole Genome Analysis of Leptospira licerasiae Provides Insight into Leptospiral Evolution and Pathogenicity. PLoS Negl Trop Dis. 2012 Oct 25; 6(10): e1853.
Agampodi SB, Moreno A, Vientz JM, Matthias MA. Utility and Limitations of Direct Multi-locus Sequence Typing on qPCR-Positive Blood to Determine Infecting Leptospira Strain. Am J Trop Med Hyg. 2012 Dec 3.