Faculty Affairs: Faculty Interests Database Christopher M. Snyder, PhD
|Microbiology & Immunology|
|Mailing Address||Contact Information|
233 S. 10th Street, BLSB 526
Philadelphia, Pennsylvania 19107
|Expertise and Research Interests|
|Our lab is interested in understanding how T cells respond to chronic antigen stimulation during persistent viral infections, particularly cytomegalovirus (CMV) infections. CMV is a ubiquitous herpesvirus that infects most people world-wide and persists for life. In healthy individuals, CMV is continuously controlled by the immune system and causes little or no pathology, thanks largely to a potent and systemic T cell surveillance effort. In contrast, CMV is a major pathogen for immunocompromised individuals, causing severe morbidity and death. In addition, if CMV is transmitted to a developing fetus, the results can be devastating. In fact, CMV is a major congenital pathogen and a leading cause of birth defects in the developed world. For this reason, a vaccine that prevents CMV transmission would be enormously beneficial. CMV is a highly species specific pathogen and human CMV (HCMV) will not replicate in non-human cells. Therefore, to study the immune response to HCMV, we use murine CMV (MCMV), a homologue of HCMV and a natural mouse pathogen. Both viruses have evolved remarkably similar overall relationships with their hosts and thus MCMV is an excellent model to study HCMV immunobiology. Currently we focus on three broad areas of research:
1) We are investigating CMV-specific T cells in the salivary gland. This mucosal tissue serves as a major site of CMV release and transmission to new hosts. We are currently investigating the migration, localization, differentiation and function of CMV-specific T cells in this unique mucosal environment, as well as whether they can be effectively induced by vaccination.
2) The systemic surveillance of CMV-infected targets has profound effects on the responding T cell populations. Most notably, these cells increase in number over the life of the host. In fact, CMV-specific T cells are the largest known populations in the blood of healthy adults, comprising 4% to 5% of all T cells in circulation. A second overarching goal of our lab is to understand this remarkable accumulation of functional T cells, a process known as "memory inflation".
3) Because CMV stimulates such large numbers of T cells, we and others have proposed using it as a vaccine vector. Indeed, large numbers of T cells can be elicited by recombinant antigens encoded in the CMV genome and we have shown that a non-pathogenic, spread-defective version of MCMV can sustain large numbers of T cells. Therefore, a third goal of our lab is to investigate CMV-based vaccines that stimulate tumor-specific immunity.
|T cells; CD8; cytomegalovirus; CMV; MCMV; murine cytomegalovirus; immune memory; chronic infection; immunology; microbiology; herpesvirus|
Last Updated by Christopher Snyder, PhD: Thursday, January 5, 2012 11:25:12 AM