Hu Recom CD40 Ligand, ACF, 10 µg

This recombinant human protein from STEMCELL Technologies is supplied as an animal component-free preparation of cluster of differentiation 40 ligand (CD40L), a type II transmembrane glycoprotein belonging to the tumor necrosis factor (TNF) superfamily. The ligand forms a bioactive homotrimer that exists as both soluble and membrane-bound forms. CD40 ligand is expressed on T cells, monocytes, basophils, eosinophils, platelets, dendritic cells, and endothelial cells, while its receptor CD40 is expressed on B cells, dendritic cells, macrophages, monocytes, platelets, endothelial cells, and epithelial cells.

Binding of CD40 ligand to CD40 stimulates B cell proliferation, immunoglobulin class switching, antibody secretion, and T cell-dependent humoral responses. Dysregulation of CD40 ligand has been linked to immune deficiency in HIV and AIDS, and the protein has also been associated with the pathology of atherosclerosis, atherothrombosis, and restenosis. The product is produced in E. coli, with a predicted molecular mass of 16.3 kDa and a purity of ≥ 95%.

Specific activity is ≥ 1 x 10^4 units/mg (EC50 ≤ 100 ng/mL), as determined by the ability to induce bioluminescence in engineered CD40L bioassay cells. Endotoxin level is ≤ 0.1 EU/μg protein as measured by kinetic Limulus amebocyte lysate (LAL) analysis. The protein is lyophilized from a sterile-filtered solution containing sodium phosphate at pH 7.5 and should be stored at -20 to -80°C, where it remains stable for 12 months from the date of receipt.