CD8 alpha is an important immune glycoprotein that serves as a coreceptor for MHC class I:peptide complexes, linking T cells to antigens presented by APCs.It interacts with TCR and MHC class I, recruits LCK kinase, and initiates multiple signaling pathways.CD8 alpha Protein, Rat (HEK293, Fc) is the recombinant rat-derived CD8 alpha protein, expressed by HEK293 , with C-hFc labeled tag.