Specificity
This antibody recognises the human CD8 antigen, a ~32 kD dimer expressed by a subset of T cells with cytotoxic/suppressor activity, and more weakly by NK cells.RPA-T4 is specific for the human CD4 antigen, a ~59 kDa cell surface glycoprotein expressed by the helper-inducer subset of T cells, and weakly by monocytes.