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...

Multiple sclerosis (MS) is an immune-mediated demyelinating disease of the CNS, and CD8 T cells are the predominant T cell population in MS lesions. Given that transfer of CNS-specific CD8 T cells results in an attenuated clinical demyelinating disease in C57BL/6 mice with immunization-induced experimental autoimmune encephalomyelitis (EAE), we investigated the cellular targets and mechanisms o...

A substantial subgroup of patients with common variable immunodeficiency (CVI) exhibit an abnormal T-cell phenotype characterized by a low CD4/CD8 ratio associated with a significant increase in the absolute number of CD8+ T cells (CVI4/8low patients). In the present study, we examined the phenotypic and functional properties of purified T-cell subsets in this group of CVI patients. CD8+ T cell...

In experimental models in which the Ag-stimulation history of memory CD8 T cell populations was clearly defined (adoptive transfer of a known number of TCR-transgenic memory CD8 T cells), all facets of the ensuing CD8 T cell responses, including proliferative expansion, duration and extent of contraction, diversification of memory CD8 T cell transcriptomes, and life-long survival, were dependen...

What governs the increased apoptosis sensitivity of HIV-specific CD8(+) T cells is poorly understood. Here, we examined the involvement of mitochondria in this apoptosis. Remarkably higher mitochondrial mass (MM) was found in HIV-specific compared with CMV-specific CD8(+) T cells from HIV(+) patients and this could not be attributed to their different differentiation status. MM(High) phenotype ...

BACKGROUND CD8(+) T-cell activation, characterized by increased CD28 expression, reduces neointima formation after arterial injury in mice. The CD8(+)CD28(hi) phenotype is associated with increased effector function. In this study, we used a mouse model that has CD8(+) but no CD4(+) T cells (CD4-/-) to assess the role of CD8(+) T cells and test the function of CD8(+)CD28(hi) T cells in modulati...

PURPOSE Patients with cancer have an increased frequency of circulating apoptosis-sensitive CD8(+)CCR7(neg) T cells and few CD8(+)CCR7(+) T cells versus normal controls. The functional and clinical significance of this imbalance was investigated using peripheral blood of patients with squamous cell carcinoma of the head and neck (HNSCC). EXPERIMENTAL DESIGN The frequency of circulating CD8(+)...

CD154, one of the most extensively studied T cell costimulation molecules, represents a promising therapeutic target in organ transplantation. However, the immunological mechanisms of CD154 blockade that result in allograft protection, particularly in the context of alloreactive CD4/CD8 T cell activation, remain to be elucidated. We now report on the profound inhibition of alloreactive CD8(+) T...

The CD8 receptor plays a central role in the recognition and elimination of virally infected and malignant cells by cytolytic CD8(+) T cells. In conjunction with the TCR, the CD8 coreceptor binds Ag-specific class I MHC (MHC-I) molecules expressed by target cells, initiating signaling events that result in T cell activation. Whether CD8 can further function as an adhesion molecule for non-Ag MH...