CD28 serves as a receptor for CD80 (B7.1) and CD86 (B7.2), proteins found on antigen-presenting cells (APCs). CD28 is the only B7 receptor consistently expressed on naive T cells. In the absence of CD28:B7 interaction, a naive T cell's TCR engagement with an MHC: antigen complex leads to anergy.

CD28 is critical for regulatory T cell survival and the maintenance of immune homeostasis. We outline the roles that CD28 and its family members play in human disease and we review the clinical efficacy of drugs that block CD28 ligands.

CD80 is the ligand for the proteins CD28 (for autoregulation and intercellular association) and CTLA-4 (for attenuation of regulation and cellular disassociation) found on the surface of T-cells. [6] [13] Interaction of CD80 with CD28 triggers costimulatory signals and results in enhanced and sustained T-cell activation. In contrast, contrary ...

For example, based on affinity data, CD80 is both the best ligand for CD28 and CTLA-4; therefore, it is conceivable that CD80 knockouts do not display a CTLA-4 KO-like phenotype because the proliferative drive via CD28–CD80 interactions has also been eliminated.

Nov 19, 2001 · CD28 interacts with CD80 (also known as B7-1) and CD86 (B7-2), which are expressed on the APC in response to activating signals that result from, for example, CD40 engagement.

Feb 3, 1997 · The structurally related T cell surface molecules CD28 and CTLA-4 interact with cell surface ligands CD80 (B7-1) and CD86 (B7-2) on antigen-presenting cells (APC) and modulate T cell antigen recognition.

CD28 is a prominent co-receptor in naïve and memory T-cell responses. Its blockade has been exploited clinically to dampen T-cell responses to self-antigen.

This article reviews the CD28/CTLA4 and CD80/CD86 families, and outlines the functional outcomes and biochemical signaling pathways recruited after CD28 ligation. T cell stimulation in the absence of a second, costimulatory signal can lead to anergy or the induction of cell death.

Jul 31, 2018 · In this study, we developed an agent-based model based on SBS and centripetal F-actin transport of molecules with the aim to determine the mechanisms driving the particular localization of CD28-CD80.

Dec 12, 2014 · However, in the presence of high, but not low, concentrations of CD80, Tregs form stationary, symmetrical synapses. Using blocking antibodies, we show that, while CTLA-4 is required for CD80 downmodulation, CD28-CD80 interactions are critical for modulating Treg motility in the presence of antigen.