anti-CD28 (human), mAb (ANC28.1/5D10)

Human CD28 is an important costimulatory molecule found on all CD4+ T cells and on about half of the CD8+ T cells. T cell activities attributed to CD28 include prevention of anergy, induction of cytokine gene transcription, stabilization of cytokine mRNA and activation of CD8+ cytotoxic T lymphocytes. The ligands for CD28 identified as CD80 (B7-1) and CD86 (B7-2) are immunglobulin superfamily monomeric transmembrane glycoproteins of 60kDa and 80kDa respectively. Anti-CD28 antibodies have been shown to have a strong adjuvant effect when conjugated to an immunogen. Monovalency of the CD28 receptor for its natural ligands is essential to provide costimulation without inducing responses in the absense of TCR engagement.