CD8b Antibody – Mouse Monoclonal

The CD8 antigen is a cell surface glycoprotein found on most cytotoxic T lymphocytes that mediates efficient cell-cell interactions within the immune system. The CD8 antigen, acting as a coreceptor, and the T-cell receptor on the T lymphocyte recognize antigens displayed by an antigen presenting cell (APC) in the context of class I MHC molecules. The functional coreceptor is either a homodimer composed of two alpha chains, or a heterodimer composed of one alpha and one beta chain. Both alpha and beta chains share significant homology to immunoglobulin variable light chains. This gene encodes the CD8 beta chain isoforms. Multiple alternatively spliced transcript variants encoding distinct membrane associated or secreted isoforms have been described. A pseudogene, also located on chromosome 2, has been identified. [provided by RefSeq, May 2010]

Function: Identifies cytotoxic/suppressor T-cells that interact with MHC class I bearing targets. CD8 is thought to play a role in the process of T-cell mediated killing.

Subunit structure: In general heterodimer of an alpha and a beta chain linked by two disulfide bonds.

Subcellular location: Isoform 1: Cell membrane; Single-pass type I membrane protein

Probable. Isoform 2: Cell membrane; Single-pass type I membrane protein

Probable. Isoform 3: Secreted

Probable. Isoform 4: Cell membrane; Single-pass type I membrane protein

Probable. Isoform 5: Cell membrane; Single-pass type I membrane protein

Probable. Isoform 6: Secreted

Probable. Isoform 7: Secreted

Probable. Isoform 8: Secreted

Probable.

Tissue specificity: Isoform 1, isoform 3, isoform 5, isoform 6, isoform 7 and isoform 8 are expressed in both thymus and peripheral CD8+ T-cells. Expression of isoform 1 is higher in thymus CD8+ T-cells than in peripheral CD8+ T-cells. Expression of isoform 6 is higher in peripheral CD8+ T-cells than in thymus CD8+ T-cells. Ref.7

Post-translational modification: Phosphorylated as a consequence of T-cell activation

Potential.

Sequence similarities: Contains 1 Ig-like V-type (immunoglobulin-like) domain.

Sequence caution: The sequence AAD13877.1 differs from that shown. Reason: Erroneous gene model prediction.