Human CD154 (CD40 Ligand) is a member of the tumor necrosis factor (TNF) family and is expressed on the surface of activated T cells. Interaction of CD154 and CD40 is essential for isotype switching in B cells. Known genetic defects that alter this interaction lead to impaired immune system function (1). CD154 has been shown to be hyperexpressed by B and T cells in SLE patients (4). CD154 has been reported to be expressed on vascular endothelial cells, smooth muscle cells and macrophages indicating a possible role for the CD40-CD154 immunoregulatory signaling mechanism during inflammation and immunity in atherogenesis (6).
Isotype: Murine IgG1
Immunogen: Human sgp39 fusion protein
Specificity: Antibody 24-31 immunoprecipitates a CD154 (gp39) molecule of about 39 kd. This clone has been reported to cross react with Cynomolgus and Rhesus Monkey CD154. Binding avidity of clone 24-31 to CD154 was reported to be 8.5 nM Kd (11).
Functional Application: The antibody 24-31 will block MLR, sgp39 induced human B cell proliferation and T cell dependent B cell differentiation (9).
1. D. Gray, et al, (1994) Seminars in Immunol 6: 303-310.
2. F. Pietravalle, et al, (1996) J Biol Chemistry 271: 5965-5967.
3. R.J. Noelle, (1996) Immunity 4: 415-419.
5. I.S. Grewal and R.A. Flavell, (1996) Immunol Today 17: 410-414.
6. F. Mach, et al, (1997) Proc Natl Acad Sci USA 94:1931-1936.
7. F. Pietraville, et al, (1996) Eur J. Immunol 26:725-728.