The CD8 co-receptor can modulate CD8 T cell function through its contributions to T cell receptor (TCR) binding and signaling. Here we show that IFNand IL-4 exert opposing effects on the expression of CD8 mRNA and surface CD8 protein during CD8 T cell activation. IL-4 caused down-regulation of surface CD8 on ovalbumin (OVA)257–264-specific TCR-transgenic OT-I CD8 T cells activated with OVA257–2...

Antitumor immune response is usually inhibited by immunosuppressive tumor microenvironment. CD8+CD28T lymphocyte (Ts; or CD8+ Treg) is another regulatory T cell apart from CD4+CD25highCD127low Treg, and it has been detected infiltrating in tumor tissue of various types as well. The aim of this study is to investigate possible role of both Tregs in peripheral circulation of non small cell lung c...

Elimination of lymphoid tissue reservoirs is a key component of HIV eradication strategies. CD8+ T cells play a critical role in control of HIV, but their functional attributes in lymph nodes (LNs) remain unclear. Here, we show that memory, follicular CXCR5+, and HIV-specific CD8+ T cells from LNs do not manifest the properties of cytolytic CD8+ T cells. While the frequency of follicular CXCR5+...

Protection against many intracellular pathogens is provided by CD8 T cells, which are thought to need CD4 T cell help to develop into effective memory CD8 T cells. Because murine CD8 T cells do not transcribe MHC class II (MHC-II) genes, several models have proposed antigen presenting cells (APCs) as intermediaries required for CD4 T cells to deliver their help to CD8 T cells. Here, we demonstr...

BACKGROUND & AIMS The requirement for costimulation of CD8 T-cell priming and restimulation by nonprofessional antigen-presenting cells is unresolved. Here, we investigated whether B7-H1 (CD274, PD-L1) on hepatocytes (HC) is involved in the specific activation of naive CD8 T cells or activated CD8 T blasts. METHODS Naive or activated CD8 T cells from transgenic OT-I mice were primed/restimula...

immune system, dendritic cells (DCs) are specialized Ag-presenting cells that have a dominant role in the initiation of T cell responses. For this, DCs present intracellular Ags in MHC class I molecules to CD8 T cells or extracellular Ags in MHC class II to CD4 T cells, respectively. Next to these two classical Ag-presentation pathways, DCs are also able to cross-present extracellular Ags in th...

The two-colour flow cytometry method applied in a routine enumeration of peripheral blood T lymphocyte subsets reveals that in some patients the entire population of CD4+ lymphocytes seems to express CD8 determinants as well. However, expression of the CD8 antigens on the cell surface is much lower in comparison with typical CD8+ cells. Moreover, in one-colour staining with an anti-CD8 antibody...

BACKGROUND Chronic antigenic stimulation by cytomegalovirus (CMV) is thought to increase "immunosenesence" of aging, characterized by accumulation of terminally differentiated CD28- CD8+ T cells and increased CD57, a marker of proliferative history. Whether chronic HIV infection causes similar effects is currently unclear. METHODS We compared markers of CD8+ T cell differentiation (e.g., CD28...

NKG2D mediates an important costimulatory pathway in CD8 T cells. In HIV infection, the authors found that NKG2D expression on both total CD8 and HIV-specific CD8 T cells was significantly lower in viremic patients than in HIV controllers. Antiretroviral therapy partially restored NKG2D expression on HIV-specific CD8 T cells. The authors observed a negative correlation between the respective ex...