Anti-CD28 Monoclonal Antibody (Clone:JJ319)

CD28 is the critical T cell costimulatory receptor which provides to the cell the important second activation signal by binding CD80 and CD86 that are expressed by antigen presenting cells. Besides its costimulation role CD28 functions in preventing T cells from anergic hyporesponsive state or from undergoing premature apoptotic cell death. Its analog CTLA-4, expressed on the surface of activated T cells, has higher affinity to CD80 and CD86 than CD28 and downregulates T cell activity.