Anti-Hu CD8a, SK1, PE, 25tests

From STEMCELL Technologies, this PE-conjugated monoclonal antibody targets CD8a and is supplied as a mouse monoclonal IgG1, kappa reagent. The antibody was raised in BALB/c mice against human peripheral blood T lymphocytes and is produced by the SK1 clone. It reacts with CD8a of human, rhesus, cynomolgus, chimpanzee, African Green Monkey, Pigtailed Macaque, and Sooty Mangabey origin.

CD8a, also known as Leu2 or T8, is a 32–34 kDa type I transmembrane glycoprotein that forms the α subunit of CD8. CD8 exists as a disulfide-bonded αβ heterodimer with CD8b, or as an αα homodimer, and acts as a co-receptor to the T cell receptor during T cell activation by binding MHC class I molecules presented by an antigen-presenting cell. The CD8a chain binds to the α3 domain of class I MHC molecules, strengthening the TCR–MHC I–antigen interaction and amplifying downstream signalling through association with cytoplasmic tyrosine kinases such as Lck. CD8a is expressed by a majority of thymocytes, a subset of mature peripheral blood T cells (cytotoxic T cells), a proportion of γδ T cells, and at lower levels by NK cells, which predominantly express the CD8a homodimer. Published reports indicate that the SK1 antibody blocks MHC:peptide tetramer binding to the TCR and inhibits proliferation of Leu-2+ T cells in mixed leukocyte reactions.

The reagent has been verified for flow cytometry (FC), with additional reported use in FC. It is formulated as a phosphate-buffered solution at pH 7.2, containing 0.09% sodium azide and 0.2% (w/v) bovine serum albumin, and has been purified by affinity chromatography prior to PE conjugation; the supplied solution is free of unconjugated PE and unconjugated antibody. For flow cytometry, the manufacturer's suggested use is 5 µL per 1 × 10^6 cells in 100 µL, or per 100 µL of whole blood, with titration recommended for each application. The product should be stored undiluted at 2–8 °C, protected from prolonged exposure to light and not frozen. STEMCELL Technologies' quality management system is certified to ISO 13485, and the product is intended for research use only.