T-cell-specific surface glycoprotein CD28 (CD28) (CD28)

CD28 is a critical co-stimulatory receptor constitutively expressed on the surface of T cells, playing a central role in the adaptive immune response [1, 11]. It belongs to the immunoglobulin superfamily and provides the essential "second signal" required for full T cell activation, proliferation, and survival upon binding to its ligands, CD80 (B7-1) and CD86 (B7-2), on antigen-presenting cells [1, 10]. This signaling pathway is vital for the production of cytokines like interleukin-2 and for preventing T cell anergy [1, 11]. In therapeutic contexts, CD28 is a major target for immunomodulation; its blockade using agents like Abatacept is employed to treat autoimmune disorders such as rheumatoid arthritis and to prevent organ transplant rejection [8, 10]. Conversely, CD28 signaling domains are frequently incorporated into chimeric antigen receptor (CAR) T-cell therapies to enhance their persistence and anti-tumor efficacy [17, 18]. However, therapeutic manipulation of CD28 carries significant risks, as superagonistic activation can trigger life-threatening cytokine release syndrome and multiple organ failure [1, 15].

Other names

Tp44CD28 antigenCD28 moleculeT-cell-specific surface glycoprotein CD28

Co-stimulation blockade through competitive inhibition of B7-1 (CD80) and B7-2 (CD86) ligand binding; direct agonism or superagonism to induce T cell activation and expansion.