anti-CD28 (human), Rabbit Monoclonal (RM404)

CD28 is a homodimeric T cell specific surface glycoprotein. CD28 is a cell adhesion molecule of the immunoglobulin superfamily which is constitutively expressed on most peripheral blood T lymphocytes. Moreover, CD28 is the critical T cell costimulatory receptor that provides the cell the important second activation signal by binding CD80 and CD86 which are expressed by antigen presenting cells. In addition to its co-stimulation role, CD28 functions by preventing T cells from entering an anergic-hyporesponsive state or from undergoing premature apoptotic cell death. In murine peripheral lymphoid organs and in the blood, all CD4+ and CD8+ T cells express CD28. Diseases associated with CD28 dysfunction include mycosis fungiodes and Sezary's Disease.