CD5, also known as Leu-1, Ly-1, and T1, is a 67 kDa transmembrane glycoprotein in the scavenger receptor superfamily. CD5 has been shown to interact homophilically, with CD72 on B cells, and with beta-glucan components of fungal cell walls. CD5 expression on developing thymocytes is positively regulated by signaling through the T cell antigen receptor (TCR) and is upregulated on tolerized peripheral CD4+ cells. It inhibits TCR signaling and promotes T cell nonresponsiveness and survival. CD5 signaling inhibits the generation of regulatory T cells but promotes the development of Th17 cells. Within the B cell lineage, CD5 is expressed on B-1a cells, anergic B cells, and IL-10 producing regulatory B cells. Similarly to on T cells, it negatively regulates signaling through the B cell antigen receptor and supports peripheral B cell survival, anergy, and tolerance. B cells can produce an intracellularly-retained form of CD5 which lacks the signal peptide and a portion of the first SRCR domain. CD5 is also involved in the cellular entry of hepatitis C virus into T cells. Specifications Synonyms CD5 molecule; CD5; LEU1; T1; CD5 antigen Uniprot No. P06127 Source Recombinant Human CD5 Protein is expressed from HEK293 Cells with hFc tag and Avi tag at the C-terminal. It contains Arg25-Asn371. Molecular Weight Approximately 67.1 kDa. Due to glycosylation, the protein migrates to 75-82 kDa based on Tris-Bis PAGE result. Purity > 95% as determined by SDS-PAGE and HPLC. Activity ELISA Data: Immobilized Human CD5 at 0.5μg/ml (100μl/Well) on the plate. Dose response curve for Biotinylated Anti-CD5 Antibody, hFc Tag with the EC50 19.6ng/ml determined by ELISA. Endotoxin < 1.0 EU per 1μg of the protein by the LAL method. Formulation Lyophilized from 0.22 μm filtered solution in PBS (pH 7.4). Normally 5% trehalose is added as protectant before lyophilization. Reconstitution Centrifuge tubes before opening. Reconstituting to a concentration more than 100 μg/mL is recommended (usually we use 1 mg/mL solution for lyophilization). Dissolve the lyophilized protein in distilled water. Storage The product should be stored at -20~-80℃ for 1 year from date of receipt. 2-7 days, 2 ~8 °C under sterile conditions after reconstitution. 3-6 months, -20~-80℃ under sterile conditions after reconstitution. Recommend to aliquot the protein into smaller quantities when first used and avoid repeated freeze-thaw cycles. Note 1.Avoid repeated freezing and thawing. 2.Please operate with lab coats and disposable gloves, for your safety. 3.This product is for research use only. Product Data
