CD86 Human Protein

This gene encodes a type I membrane protein that is a member of the immunoglobulin superfamily. This protein is expressed by antigen-presenting cells, and it is the ligand for two proteins at the cell surface of T cells, CD28 antigen and cytotoxic T-lymphocyte-associated protein 4. Binding of this protein with CD28 antigen is a costimulatory signal for activation of the T-cell. Binding of this protein with cytotoxic T-lymphocyte-associated protein 4 negatively regulates T-cell activation and diminishes the immune response. Alternative splicing results in several transcript variants encoding different isoforms.[provided by RefSeq, May 2011]

CD86: Receptor involved in the costimulatory signal essential for T-lymphocyte proliferation and interleukin-2 production, by binding CD28 or CTLA-4. May play a critical role in the early events of T-cell activation and costimulation of naive T-cells, such as deciding between immunity and anergy that is made by T- cells within 24 hours after activation. Isoform 2 interferes with the formation of CD86 clusters, and thus acts as a negative regulator of T-cell activation. 4 isoforms of the human protein are produced by alternative splicing.

Protein type: Membrane protein, integral; Immunoglobulin superfamily

Chromosomal Location of Human Ortholog: 3q21

Cellular Component: cell surface; intracellular membrane-bound organelle; plasma membrane; integral to membrane; external side of plasma membrane

Molecular Function: protein binding; coreceptor activity; receptor activity; receptor binding

Biological Process: positive regulation of lymphotoxin A biosynthetic process; negative regulation of T cell anergy; nerve growth factor receptor signaling pathway; viral reproduction; T cell activation; positive regulation of interleukin-2 biosynthetic process; positive regulation of transcription, DNA-dependent; myeloid dendritic cell differentiation; positive regulation of activated T cell proliferation; positive regulation of interleukin-4 biosynthetic process; positive regulation of T-helper 2 cell differentiation; cell-cell signaling; T cell proliferation during immune response; positive regulation of cell proliferation; response to yeast; defense response to virus; aging; epidermal growth factor receptor signaling pathway; response to drug; fibroblast growth factor receptor signaling pathway; phosphoinositide-mediated signaling; B cell activation; T cell costimulation; toll-like receptor signaling pathway; innate immune response; immune response