Anti-CD21 (CR2, C3d Receptor, EBV Receptor)

CD21 (also EBV receptor and CR2) is a 145kD member of the RCA (receptors of complement activation) family of proteins. It is expressed on T cells, B cells, and follicular dendritic cells. On the B cell surface, it combines with the BCR and CD19 to form a B cell activating complex. Mature human CD21 is 1011aa in length. It is a type I transmembrane (TM) protein that contains a 951aa extracellular domain (ECD) (aa21-971) and a short 34aa cytoplasmic tail. The ECD exhibits fifteen 60aa SUSHI repeats. Soluble CD21 is apparently generated by cleavage near the TM domain. One potential splice variant shows a deletion of (aa 847-908), while another shows an insertion of 59aa after Lys659. The ECD of human CD21 is 71% aa identical to mouse CD21 ECD. Applications: Suitable for use in Flow Cytometry, ELISA, Western Blot. Other applications not tested. Recommended Dilution: Flow Cytometry: 25ug/ml, Direct ELISA: 0.5-1ug/ml, Western Blot: 2ug/ml, Optimal dilutions to be determined by the researcher. Hybridoma: Myeloma cells with B cells from Balb/c mice. Storage and Stability: Lyophilized powder may be stored at -20°C. Stable for 12 months at -20°C. Reconstitute with sterile PBS. Aliquot to avoid repeated freezing and thawing. Store at -20°C. Reconstituted product is stable for 12 months at -20°C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.