The formation of memory CD8 T cells is an important goal of vaccination. However, although widespread use of booster immunizations in humans generates secondary and tertiary CD8 T cell memory, experimental data are limited to primary CD8 T cell memory. Here, we show that, compared with primary memory CD8 T cells, secondary memory CD8 T cells exhibit substantially delayed conversion to a central...

Although it is well documented that CD8 T cells play a critical role in controlling chronic viral infections, the mechanisms underlying the regulation of CD8 T-cell responses are not well understood. Using the mouse model of an acute and chronic lymphocytic choriomeningitis virus (LCMV) infection, we have examined the relative importance of peripheral T cells and thymic emigrants in the elicita...

Prolonged antiretroviral therapy (ART) with effective HIV suppression and reconstitution of CD4 T cells, fails to restore CD8 T cell lytic effector function that is needed to eradicate the viral reservoir. Better understanding of the phenotype and function of circulating CD8 cells in HIV patients will contribute to new targeted therapies directed at increasing CD8 T cell lytic effector function...

BACKGROUND We investigated respiratory syncytial virus (RSV)-specific CD8(+) memory T cell responses in healthy control participants (n=31) and in patients with chronic obstructive pulmonary disease (COPD) (n=9), with respect to frequency, memory phenotype, and proliferative requirements. METHODS The properties of RSV-specific CD8(+) T cells were analyzed by use of RSV tetramers. The prolifer...

Sézary syndrome (SS) is a leukemic variant of cutaneous T cell lymphoma (CTCL), and the neoplastic CD4+ T cells of SS patients undergo intense clonal proliferation. Although Sézary cells have been studied extensively, studies on adaptive immunity regarding CD8+T cells are scarce. This study aimed to investigate activation marker expression in CD8+ T cells according to the differentiation stages...

To understand the mechanism regulating the effector function of memory CD8 T cells, we examined expression and chromatin state of a key transcription factor (eomesodermin, EOMES) and two of its targets: perforin (PRF1) and granzyme B (GZMB). Accessible chromatin associated histone 3 lysine 9 acetylation (H3K9Ac) was found significantly higher at the proximal promoter and the first exon region o...

Programmed death-1 (PD-1) is a critical mediator of virus-specific CD8+ T-cell exhaustion. Here, we examined the expression of PD-1 on simian immunodeficiency virus (SIV)-specific CD8+ T cells and its possible involvement in regulation of cytokine production, proliferation, and survival of these cells. The majority of SIV-specific CD8+ T cells expressed a PD-1(high) phenotype, independent of th...

The important role of the CD8+ T-cells on HIV control is well established. However, correlates of immune protection remain elusive. Although the importance of CD8+ T-cell specificity and functionality in virus control has been underscored, further unraveling the link between CD8+ T-cell differentiation and viral control is needed. Here, an immunophenotypic analysis (in terms of memory markers a...

The activation, localization, phenotypic changes, and function of CFSE-labeled naive influenza-specific CD8(+) and CD4(+) T cells following influenza infection were examined. Response of adoptively transferred CD8(+) T cells was seen earliest in draining lymph node. Highly activated cells were found later in the lung, airways, and spleen, were cytolytic, and expressed IFN-gamma upon restimulati...

We investigated the effects of IL-18 on the development of CD8+ effector T cells in DBA/2 anti-BDF1 whole spleen cell MLC and compared the results with those of IL-12. Addition of IL-18 to the MLC resulted in a twofold increase in CD8/CD4 ratios compared with the control cultures when cells were expanded in IL-2-containing medium following MLC. Purified CD8+ T cells recovered from the IL-18-sti...