CD8b Brilliant Violet 711 (341, Mouse) - Reactivity: Rat

The 341 monoclonal antibody specifically recognizes the β chain of the CD8 antigen on most thymocytes and a subpopulation of mature T lymphocytes (ie, MHC class I-restricted T cells, including most T suppressor/cytotoxic cells). The CD8 α and β chains (CD8a and CD8b, respectively) form a heterodimer on the surface of most thymocytes and thymus-dependent T suppressor/cytotoxic cells, whereas intestinal intraepithelial lymphocytes, many CD8+ T cells of athymic rats, many activated CD4+ T cells, and most NK cells express CD8a without CD8b.  It has been suggested that the expression of the CD8a/CD8b heterodimer is restricted to thymus-derived T lymphocytes.  CD8 is an antigen co-receptor on the T cell surface which interacts with MHC class I molecules on antigen-presenting cells.  It participates in T-cell activation through its association with the T-cell receptor complex and protein tyrosine kinase lck.  Macrophages have also been reported to express CD8 α and β chains, which are involved in signal transduction.  The 341 mAb blocks proliferative and cytotoxic in vitro responses of CD8+ effectors to allogeneic cells.