CD8 beta

CD8B, also named P37 and LEU2, serves as the beta subunit of CD8 molecule with one Ig-like V-type domain. It mainly expresses on cytotoxic T lymphocytes and forms a heterodimer with CD8α. As an essential co-receptor, it cooperates with TCR to recognize MHC class I-restricted antigens on APCs and stabilizes immune cell interactions. The CD8B gene generates multiple spliced variants encoding membrane-bound and secreted isoforms, and participates in T cell activation and cytotoxic immune responses.