Bcl-2 plays a critical role in regulating cell survival and apoptosis. We examined Bcl-2 expression in virus-specific CD8 T cells during the expansion, death, and memory phases of the T cell response following infection of mice with lymphocytic choriomeningitis virus (LCMV). Naive CD8 T cells expressed a basal level of Bcl-2 that was down-regulated in effector CD8 T cells just before the death ...

CD8 T cells play an important role in controlling viral infections. We investigated the in situ localization of simian immunodeficiency virus (SIV)-specific T cells in lymph and genital tissues from SIV-infected macaques using MHC-class I tetramers. The majority of tetramer-binding cells localized in T cell zones and were CD8(+). Curiously, small subpopulations of tetramer-binding cells that ha...

BACKGROUND CD8(+) T cell responses develop rapidly during infection and are swiftly reduced during contraction, wherein >90% of primed CD8(+) T cells are eliminated. The role of apoptotic mechanisms in controlling this rapid proliferation and contraction of CD8(+) T cells remains unclear. Surprisingly, evidence has shown non-apoptotic activation of caspase-3 to occur during in vitro T-cell prol...

The lungs are frequently challenged by viruses, and resident CD8(+) T cells likely contribute to the surveillance of these pathogens. To obtain insight into local T cell immunity to respiratory viruses in humans, we determined the specificity, phenotype, and function of lung-residing CD8(+) T cells and peripheral blood CD8(+) T cells in a paired analysis. The lung contained markedly higher freq...

background: cd8+ cytotoxic t lymphocytes have been recently divided based on their cytokine expression profile. objective: to evaluate the percentages of cd8+ lymphocytes and their effector subsets including tc1, tc2 and tc17 in the tumor draining lymph nodes (tdlns) of patients with breast cancer. methods: single cell suspensions were obtained from tdlns of 42 patients with breast cancer. stai...

Expression of the IL-7 receptor α-chain (CD127) is decreased on CD8 T-cells in HIV infected patients and partially recovers in those receiving antiretroviral therapy with sustained viral suppression. We have shown that soluble HIV Tat protein down regulates CD127 expression on CD8 T-cells isolated from healthy HIV-negative individuals. Tat is taken up by CD8 T-cells via endocytosis, exits the e...

During infection with viruses that establish latency, the immune system needs to maintain lifelong control of the infectious agent in the presence of persistent Ag. By using a gamma-herpesvirus (gammaHV) infection model, we demonstrate that a small number of virus-specific central-memory CD8+ T cells develop early during infection, and that virus-specific CD8+T cells maintain functional and pro...

background: regulatory t cells have been suggested to have a protective role against acute rejection in allograft recipients. however, there is little information available about their contribution to chronic rejection process. the role of transforming growth factor-beta 1 (tgf- β1) as a profibrogenic and/or immunoregulatory cytokine in renal allografts is also controversial. objectives: to eva...

Although CD8 T cell-mediated immunosuppression has been a well-known phenomenon during the last three decades, the nature of primary CD8 T suppressor cells and the mechanism underlying their generation remain enigmatic. We demonstrated that naive CD8 T cells primed with allogeneic CD40 ligand-activated plasmacytoid dendritic cells (DC)2 differentiated into CD8 T cells that displayed poor second...