Background: CD4+ and CD8+ T cells are the main types of lymphocytes in cell-mediated immunity and play a central role in the induction of efficient immune responses against tumors. The frequencies of T cell subtypes in the peripheral blood and tumor tissues, and draining lymph nodes (dLN) can be considered as useful markers for evaluation of the immune system in cancers. Methods: In this study,...

B6.K(b-)D(b-) mice are devoid of class Ia but express normal levels of class Ib molecules. They have low levels of CD8 T cells in both the thymus as well as peripheral T cell compartments. Although the percentage of splenic CD8 alpha alpha T cells is increased in these animals, approximately 90% of CD8 T cells are CD8 alpha beta. In contrast to B6 animals, most of the CD8 T cells from these mic...

behcet disease (bd) is a systemic inflammatory disease of the unknown etiology. there is however, some evidence to suggest that immunological abnormalities are important in its pathogenesis, furthermore several t-cell abnormalities which may be quite relevant to autoimmune origin of the disease have been described. we report here our study of t-cell subsets, b and nk cells in 68 patients with b...

The adaptive immune response of human CD8 T cells to invading pathogens involves the differentiation of naive cells into memory and effector cells. However, the lineage relationship between memory and effector cells and the differentiation of CD8 T cells into distinct subsets of effector cell subpopulations are subjects of considerable debate. CD7 identifies three populations of CD8 T cells: CD...

We previously showed that CD8+ T cells are required for optimal primary immunity to low dose Leishmania major infection. However, it is not known whether immunity induced by low dose infection is durable and whether CD8+ T cells contribute to secondary immunity following recovery from low dose infection. Here, we compared primary and secondary immunity to low and high dose L. major infections a...

The roles(s) of CD8 T cells during infections by intracellular bacteria that reside in host cell endocytic compartments are not well understood. Our previous studies in a mouse model of human monocytotropic ehrlichiosis indicated that CD8 T cells are not essential for immunity. However, we have observed an unexpected role for these cells during challenge infection. Although immunocompetent mice...

Recently, we identified two subsets of CCR7(-) memory CD8(+) T cells expressing high and low levels of the IL-7R alpha-chain (IL-7Ralpha) that is essential for memory T cell survival in human peripheral blood. IL-7Ralpha(low)CCR7(-) memory CD8(+) T cells that produce effector cytokines and perforin have impaired proliferation and survival in response to TCR triggering and IL-7, respectively. Th...

CD4+ T cells enhance tumor destruction by CD8+ T cells. One benefit that underlies CD4+ T cell help is enhanced clonal expansion of newly activated CD8+ cells. In addition, tumor-specific CD4+ help is also associated with the accumulation of greater numbers of CD8+ T cells within the tumor. Whether this too is attributable to the effects of help delivered to the CD8+ cells during priming within...

Background: Cytotoxic CD8+ T cells, as essential parts of the adaptive immune system, play pivotal roles in anti-tumor immune responses. It is well documented that cytokine expression profiles and activation status of these cells during anti-tumor immune responses affect the outcome of host-tumor interaction. Objective: To investigate the percentages of CD8+ lymphocytes and their subsets in...