CD21 Antibody

• Catalog Number: orb2641444
• Category: Antibodies
• Description: Recognizes a protein of 140kDa, which is identified as the complement receptor 2 (CR2)/CD21. Its epitope is located in 5-8 short consensus repeats (SCRs). This mAb is highly specific to CR2 and shows no cross-reaction with CR1. This protein is expressed strongly on mature B cells, follicular dendritic cells and weakly on immature thymocytes and T lymphocytes. In B-cell ontogeny, CD21 appears after the pre-B-stage, is maintained during peripheral B-cell development and is lost upon terminal differentiation into plasma cells. CD21 expression is also gradually lost after stimulation of B cells in vitro. CD21 functions as receptor for C3d, C3dg and iC3b Complement components, for EBV and for IFNalpha. CD21 binds to CD23 and associates with CD19, CD81 and Leu13 to form a large signal-transduction complex involved in B cell activation.
• Clonality: Monoclonal
• Species/Host: Mouse
• Isotype: Mouse IgG1, kappa
• Conjugation: Unconjugated
• Reactivity: Human
• Buffer/Preservatives: 0.2 mg/ml in 1X PBS with 0.1 mg/ml rAlbumin (US sourced) and 0.05% sodium azide
• Purity: Protein G affinity chromatography
• Immunogen: A portion of amino acids 142-240 from the human protein was used as the immunogen for the CD21 antibody.
• UniProt ID: P20023
• Tested applications: ELISA, FACS, IF, IHC-P, WB
• Dilution range: ELISA (order BSA/sodium azide-free format for coating),Flow cytometry: 1-2ug/million cells,Western blot: 1-2ug/ml,Immunofluorescence: 1-2ug/ml,Immunohistochemistry (FFPE): 1-2ug/ml for 30 min at RT
• Application notes: Optimal dilution of the CD21 antibody should be determined by the researcher.1. The prediluted format is supplied in a dropper bottle and is optimized for use in IHC. After epitope retrieval step (if required), drip mAb solution onto the tissue section and incubate at RT for 30 min.
• Antibody Type: Primary Antibody
• Clone Number: CR2/2754
• Formula: 0.2 mg/ml in 1X PBS with 0.1 mg/ml BSA (US sourced) and 0.05% sodium azide
• Storage: Maintain refrigerated at 2-8°C for up to 2 weeks. For long term storage store at -20°C in small aliquots to prevent freeze-thaw cycles.
• Hazard Information: This CD21 antibody is available for research use only.
• Note: For research use only

SDS-PAGE analysis of purified, BSA-free CD21 antibody (clone CR2/2754) as confirmation of integrity and purity.

Western blot testing of human Raji cell lysate with CD21 antibody (clone CR2/2754).

Analysis of HuProt (TM) microarray containing more than 19, 000 full-length human proteins using CD21 antibody (clone CR2/2754). These results demonstrate the foremost specificity of the CR2/2754 mAb. Z- and S- score: The Z-score represents the strength of a signal that an antibody (in combination with a fluorescently-tagged anti-IgG secondary Ab) produces when binding to a particular protein on the HuProt (TM) array. Z-scores are described in units of standard deviations (SD's) above the mean value of all signals generated on that array. If the targets on the HuProt (TM) are arranged in descending order of the Z-score, the S-score is the difference (also in units of SD's) between the Z-scores. The S-score therefore represents the relative target specificity of an Ab to its intended target.

IHC testing of FFPE human tonsil tissue with CD21 antibody (clone CR2/2754). HIER: boil tissue sections in pH6, 10mM citrate buffer, for 10-20 min followed by cooling at RT for 20 min.

Immunofluorescent staining of PFA-fixed human MOLT4 cells with CD21 antibody (clone CR2/2754, green) and Reddot nuclear stain (red).

Flow cytometry staining of PFA-fixed human MOLT4 cells with CD21 antibody; Red = isotype control, Blue = CD21 antibody.