Biotinylated Recombinant Human/Cynomolgus/Rhesus macaque CD28(His-Avi Tag)

Description :
FAQ COA 已发表文献 CD28 and CTLA-4, together with their ligands, B7-1 and B7-2, constitute one of the dominant co-stimulatory pathways that regulate T and B cell responses. CD28 and CTLA-4 are structurally homologous molecules that are members of the immunoglobulin (Ig) gene superfamily. Both CD28 and CTLA-4 are composed of a single Ig V-like extracellular domain, a transmembrane domain and an intracellular domain. CD28 and CTLA-4 are both expressed on the cell surface as disulfide-linked homodimers or as monomers. The genes encoding these two molecules are closely linked on human chromosome 2 and mouse chromosome 1. Mouse CD28 is expressed constitutively on virtually 100% of mouse T cells and on developing thymocytes. Cell surface expression of mouse CD28 is down-regulated upon ligation of CD28 in the presence of PMA or PHA. In contrast, CTLA-4 is not expressed constitutively but is up-regulated rapidly following T cell activation and CD28 ligation. Cell surface expression of mouse CTLA-4 peaks approximately 48 hours after activation. Although both CTLA-4 and CD28 can bind to the same ligands, CTLA-4 binds to B7-1 and B7-2 with a 20-100 fold higher affinity than CD28. CD28/B7 interaction has been shown to prevent apoptosis of activated T cells via the up-regulation of bcl-XL. CD28 ligation has also been shown to regulate Th1/Th2 differentiation. 产品性质 别名 CD28 antigen (Tp44); CD28 molecule; CD28; MGC138290 Uniprot No. P10747 Recombinant Biotinylated Human/Cynomolgus/Rhesus macaque CD28Protein is expressed from HEK293Cellswith His tag and Avi tag at the N-terminal. It contains Asn19-Pro152. 分子量 Approximately 18.2 kDa. Due to glycosylation, the protein migrates to 38-50 kDa based on Tris-Bis PAGE result. > 95% as determined by SDS-PAGEand HPLC. ELISAData: Immobilized Anti-CD28 Antibody, hFc Tag at 2g/ml (100l/well) on the plate. Dose response curve for Biotinylated Human/Cynomolgus/Rhesus macaque CD28, His Tag with the EC50 of 24.4ng/ml determined by ELISA. 内毒素 1.0EU per 1g of the protein by the LAL method. Lyophilized from 0.22m filtered solution in PBS (pH 7.4). Normally 5% trehalose is added as protectant before lyophilization. 复溶 Centrifuge tubes before opening. Reconstituting to a concentration more than 100 g/mL is recommended (usually we use 1mg/mLsolution for lyophilization). Dissolve the lyophilized protein in distilled water.