Description
CD28 is a 44 kD glycoprotein and a member of the Ig superfamily. In its capacity as a costimulatory receptor, CD28 produces co-stimulatory signals necessary for T cell activation and survival. CD28 is the only B7 receptor constitutively expressed on naive T cells. Without having this CD28/B7 interaction, T cells will fail to respond to their specific antigen when coming in contact with an MHC/antigen complex and thus, are said to be anergic