SummaryWe have previously reported that T cells bearing T cell receptors (TCRs) of 3`//$ type appear at a relatively early stage of primary infection with Listeria monocytogenes in mice. To characterize the early-appearing 3`//$ T cells during listeriosis, we analyzed the specificity and cytokine production of the 3`//$ T cells in the peritoneal cavity in mice inoculated intraperitoneally with a sublethal dose of L. monocytogenes. The early-appearing 3'//$ T cells, most of which were of CD4-CD8-phenotype, proliferated and secreted IFN-3' and macrophage chemotactic factor in response to purified protein derivative from Mycobacterium tuberculosis, or recombinant 65-kD heat-shock protein derived from M. bov/s but not to heat-killed Listeria.
SUMMARYCytomegalovirus (CMV) causes severe opportunistic infection in immunocompromised hosts. The importance of conventional ab T cells in protection against CMV infection has been well documented. However, the role of the second T-cell population (which express the cd T-cell receptor) in CMV infection is not known. In the present study, we analysed the function and protective role of cd T cells in a murine cytomegalovirus (MCMV) infection model. After intraperitoneal infection with MCMV, the number of cd T cells increased in the liver and peritoneal cavity from day 3, and reached a peak on day 5. The cd T cells showed an activated T-cell phenotype and predominantly expressed Vc1, which is known to be expressed by heat-shock protein 65 (hsp 65)-speci®c cd T cells. Analysis of cytokine expression demonstrated that the MCMV-induced cd T cells expressed interferon-c (IFN-c) and tumour necrosis factor-a (TNF-a) but not interleukin-4 (IL-4), implying their participation in the cell-mediated immune response against MCMV. Depletion of cd T cells by anti-T-cell receptor (TCR) cd monoclonal antibody (mAb) treatment resulted in signi®cant increase of virus titre and decrease of IFN-c in the liver on day 3 after MCMV infection, which further supports the importance of cd T cells in early protection against infection. Finally, the MCMV-induced cd T cells produced IFN-c in vitro in response to hsp 65. Our results suggest that cd T cells participate in early protection against MCMV infection through recognition of hsp 65 and production of IFN-c.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.