The inducible costimulator CD278 (ICOS) is similar to human CD28 (24% homology), and plays an analogous role in the T cell activation process. Secondary signaling through CD28 or CD278 results in discrete cytokine secretion profiles by the activated T cells.1 Signaling by either molecule is effectively down regulated by CD152 (CTLA-4) engagement.2 Human CD275 (ICOSL, GL50, B7-H2) is a member of the B7 family sharing ~20% homology with CD80 (B7-1) and CD86 (B7-2), and has been shown to be the ligand for CD278 (ICOS).3 Two RNA splice variants exist for this molecule, differing only in the cytoplasmic domain. 4
Isotype: Murine IgG1 Kappa
Immunogen: Human HPB-MLT cells, recombinant human CD278(ICOS)-muIg
Specificity: Antibody ANC6C6 binds to recombinant and cell surface CD278(ICOS)
Functional Application: Antibody ANC6C6 blocks binding of Recombinant CD275-muIg to CD278. It blocks CD28-superagonist/CD275(LICOS) mediated T cell proliferation in vitro(7).
1) Beier, K.C., R.A. Kroczek, et al. 2000, Eur J Immunol. 30(12):3707-3717.
2) Riley, J.L., C.H. June, et al. 2001, J. Immunol. 166: 4943-4948.
3) Ling, V., M. Collins, et al. 2000, J. Immunol. 164: 1653-1657.
4) Ling, V., M. Collins, et al. 2001, J. Immunol. 166: 7300-7308.