The activation of naive CD4+ T cells requires both TCR engagement and a second costimulatory signal mediated by the interaction of CD28 with CD80/CD86 expressed on professional APC. However, the situation for naive CD8+ T cells is less clear. Although evidence indicates that induction of CD8+ T cell responses is also dependent on professional APC, the ability of some tumors, which do not expres...

The purine analogs, fludarabine nucleoside (FdA), and cladribine (CdA) (1 μM, 24 hours), significantly changed the levels of some surface antigens on the human B-cell lines MEC2 and Raji. Changes in the surface proteins were identified using a Cluster of Differentiation (CD) antibody microarray that captures live cells and confirmed by flow cytometry. For Raji cells, CdA up-regulated CD10, CD54...

Although previous studies have shown that altered B7 costimulation plays a critical role in UV irradiation-induced regulation of immunity, the individual roles of the B7 receptors (CD28 and CTLA-4) or the B7 family members (CD80 and CD86) have not been explored. Thus, we investigated CTLA-4 signaling during photocarcinogenesis of chronically UV-B-exposed mice using an antagonistic anti-CTLA-4 A...

Abstract Monocyte exhaustion reflected in pathogenic inflammation and immune suppression underlies the pathogenesis of sepsis. The objective this study is to define novel approaches alleviating monocyte exhaustion, based on intriguing clinical reports that BCG components may be beneficial reducing polymicrobial infection-triggered sepsis severity. We recapitulated vitrothe development exhausted...

PURPOSE To examine the role of the CD28-CD80-CD86 pathway of T-lymphocyte costimulation in corneal allograft rejection and the effect of blockade of that pathway on graft survival. METHODS Kinetics of CD80 and CD86 expression in the cornea and draining lymph nodes were examined by RT-PCR and immunohistochemistry in untreated allograft recipients in a high-responder rat model. The effect of bl...

BACKGROUND The inflammatory nature of atherosclerosis provides a broad range of potential molecular targets for atherosclerosis imaging. Growing interest is focused on targets related to plaque vulnerability such as the co-stimulatory molecules CD80 and CD86. We investigated in this preclinical proof-of-concept study the applicability of the CD80/CD86-binding fusion protein belatacept as a prob...

T-cell activation is initiated after T-cell receptor binding to antigen, but also requires interactions between costimulatory molecules expressed on antigen-presenting cells. An important costimulatory molecule expressed by monocytes and activated B lymphocytes has been recently identified and termed B7-2 or B70. Independently, a new Cluster of Differentiation was defined in the Fifth Internati...

BACKGROUND Costimulation blockade has been proposed to induce allograft tolerance. We combined an antagonist anti-CD40 monoclonal antibody (mAb) with an antagonist anti-CD86 mAb in a rhesus monkey kidney allograft model. We chose this combination because it leaves CD80-CD152 signaling unimpaired, allowing for the down-regulatory effect of CD152 signaling to take place through this pathway. ME...