CD8A
GeneName
CD8A
Summary
CD8A, also known as CD8 or Lyt-2, is a 26 kDa glycoprotein that is predominantly expressed on the surface of cytotoxic T cells and plays a vital role in the adaptive immune response. It functions as a co-receptor that enhances the interaction between T cells and antigen-presenting cells by binding to MHC class I molecules. CD8A is localised to the plasma membrane and is involved in T cell activation, cytotoxic T cell differentiation, and the signalling pathways associated with T cell receptor complexes. The protein can also be found in plasma membrane rafts and in the extracellular region, highlighting its role in cell communication and immune responses.
Importance
CD8A is relevant to: - T cell-mediated immunity, as it is essential for the recognition and elimination of infected or malignant cells - Understanding autoimmune diseases, where CD8+ T cells may contribute to tissue damage - Cancer immunotherapy, particularly in the context of enhancing CD8+ T cell responses against tumours - Vaccine development, where the efficacy of vaccines often relies on robust CD8+ T cell responses to provide long-lasting immunity
Top Products
For researchers investigating CD8A, we recommend two excellent primary antibodies that cater to different experimental needs. The first is the well-cited polyclonal antibody, Anti-CD8 alpha antibody (ab4055), which has garnered 233 citations and is particularly effective for immunohistochemistry (IHC). This product is a trusted choice for those focusing on tissue samples. In addition, we offer the recombinant monoclonal antibody, Anti-CD8 alpha antibody [CAL66] (ab237709). This versatile antibody has been validated for multiple applications, including flow cytometry (FC), IHC, immunocytochemistry (ICC), and immunoprecipitation (IP), making it an excellent option for researchers seeking reliable performance across various techniques. With 111 citations, it is also gaining recognition in the scientific community. Together, these antibodies provide robust tools for studying CD8A in diverse experimental contexts. The Human CD8A ELISA Kit (ab256393) is an excellent option for researchers looking to measure CD8A levels in their samples.
Abcam Product Citation Summary
The data indicates that CD8A is being studied in various human cancers, including prostate, gastric, breast, and colon cancers, as well as in head and neck squamous cell carcinoma. The use of immunohistochemistry and immunocytochemistry highlights the importance of CD8A in understanding tumor-infiltrating lymphocytes and immune cell interactions within the tumour microenvironment.
Abcam Product Citation Table
Function
The protein expressed by the gene CD8A is an integral membrane glycoprotein crucial for immune responses, operating mainly in T-cells as a coreceptor for MHC class I molecule:peptide complexes. These peptides originate from cytosolic proteins, unlike class II peptides, which are from extracellular proteins. CD8A interacts with the T-cell receptor (TCR) and MHC class I proteins on antigen-presenting cells, recruiting the Src kinase LCK to the TCR-CD3 complex. LCK phosphorylates substrates, triggering signaling pathways that lead to the production of lymphokines, enhanced motility, adhesion, and activation of cytotoxic T-lymphocytes (CTLs), thereby aiding in the recognition and elimination of infected or tumor cells. Additionally, in natural killer (NK) cells, CD8A homodimers on the cell surface provide a survival mechanism for conjugating with and lysing multiple target cells. CD8A homodimers also facilitate the survival and differentiation of activated lymphocytes into memory CD8 T-cells. This supplementary information is collated from multiple sources and compiled automatically.
Involvement in disease
Immunodeficiency 116
IMD116
An autosomal recessive immunologic defect characterized by absence of CD8+ cells, leading to recurrent bacterial infections.
None
The disease is caused by variants affecting the gene represented in this entry.
Post-translational modifications
Palmitoylated, but association with CD8B seems to be more important for the enrichment of CD8A in lipid rafts.
O-glycosylated.
Phosphorylated in cytotoxic T-lymphocytes (CTLs) following activation.
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 dendritic cells expresses CD8A homodimers. Expressed at the cell surface of plasmacytoid dendritic cells upon herpes simplex virus-1 stimulation.
Cellular localization
- Isoform 1
- Cell membrane
- Single-pass type I membrane protein
- CD8A localizes to lipid rafts only when associated with its partner CD8B.
- Isoform 2
- Secreted
Alternative names
CD8a, MAL, CD8A, T-cell surface glycoprotein CD8 alpha chain, T-lymphocyte differentiation antigen T8/Leu-2
Database links
swissprot:P01732 swissprot:P28907 omim:107270 omim:186730 omim:186760 omim:186910 swissprot:P10747 swissprot:P10966 entrezGene:940 entrezGene:952 entrezGene:926 entrezGene:925