Recombinant Human T-cell surface glycoprotein CD8 alpha chain (CD8A), Truncated

Uniprot Id

P01732

Target Species

Human

Target Name

CD8A

Target Full Name

T-cell surface glycoprotein CD8 alpha chain

Target Function

Integral membrane glycoprotein that plays an essential role in the immune response and serves multiple functions in responses against both external and internal offenses. In T-cells, functions primarily as a coreceptor for MHC class I molecule:peptide complex. The antigens presented by class I peptides are derived from cytosolic proteins while class II derived from extracellular proteins. Interacts simultaneously with the T-cell receptor (TCR) and the MHC class I proteins presented by antigen presenting cells (APCs). In turn, recruits the Src kinase LCK to the vicinity of the TCR-CD3 complex. LCK then initiates different intracellular signaling pathways by phosphorylating various substrates ultimately leading to lymphokine production, motility, adhesion and activation of cytotoxic T-lymphocytes (CTLs). This mechanism enables CTLs to recognize and eliminate infected cells and tumor cells. In NK-cells, the presence of CD8A homodimers at the cell surface provides a survival mechanism allowing conjugation and lysis of multiple target cells. CD8A homodimer molecules also promote the survival and differentiation of activated lymphocytes into memory CD8 T-cells.

Target Involvement

CD8 deficiency, familial (CD8 deficiency)

Target Subcellular Location

[Isoform 1]: Cell membrane; Single-pass type I membrane protein.; [Isoform 2]: Secreted.

Target Tissue Specificity

CD8 on thymus-derived T-cells usually consists of a disulfide-linked alpha/CD8A and a beta/CD8B chain. Less frequently, CD8 can be expressed as a CD8A homodimer. A subset of natural killer cells, memory T-cells, intraepithelial lymphocytes, monocytes and

Target Research Area

Immunology

Target Synonyms

alpha polypeptide (p32); CD8; CD8 antigen alpha polypeptide; CD8 antigen alpha polypeptide (p32); CD8a; CD8A antigen; CD8A molecule; CD8A_HUMAN; Leu2; Leu2 T lymphocyte antigen; Ly3; LYT3; MAL; OKT8 T cell antigen; OTTHUMP00000160760; OTTHUMP00000160764; OTTHUMP00000203528; OTTHUMP00000203721; p32; T cell antigen Leu2; T cell co receptor; T-cell surface glycoprotein CD8 alpha chain; T-lymphocyte differentiation antigen T8/Leu-2; T8 T cell antigen; T8/Leu-2 T-lymphocyte differentiation antigen

Target Background

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 acts as a coreceptor with the T-cell receptor on the T lymphocyte to recognize antigens displayed by an antigen presenting cell in the context of class I MHC molecules. The coreceptor functions as either a homodimer composed of two alpha chains or as 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 alpha chain. Multiple transcript variants encoding different isoforms have been found for this gene.