CD4 is a glycoprotein critical in immune responses that binds to interleukin-16 and forms a homodimer. It enhances helper T cell-mediated immune responses and regulates processes such as defense against Gram-negative bacteria and calcium signaling. CD4 Protein, Mouse (HEK293, His) is the recombinant mouse-derived CD4 protein, expressed by HEK293 , with C-His, C-6*His labeled tag.