CD21 Polyclonal antibody

CD21 Polyclonal Antibody for WB, IHC, ELISA

Host / Isotype

Rabbit / IgG







Cat no : 24374-1-AP


C3DR, CD21, Complement C3d receptor, Complement receptor type 2, CR2, EBV receptor, Epstein Barr virus receptor, SLEB9

Tested Applications

Positive WB detected inRaji cells
Positive IHC detected inhuman tonsillitis tissue
Note: suggested antigen retrieval with TE buffer pH 9.0; (*) Alternatively, antigen retrieval may be performed with citrate buffer pH 6.0

Recommended dilution

Western Blot (WB)WB : 1:500-1:1000
Immunohistochemistry (IHC)IHC : 1:20-1:200
It is recommended that this reagent should be titrated in each testing system to obtain optimal results.
Sample-dependent, Check data in validation data gallery.

Product Information

24374-1-AP targets CD21 in WB, IF, IHC, ELISA applications and shows reactivity with human samples.

Tested Reactivity human
Cited Reactivityhuman
Host / Isotype Rabbit / IgG
Class Polyclonal
Type Antibody
Immunogen CD21 fusion protein Ag18058
Full Name complement component (3d/Epstein Barr virus) receptor 2
Calculated Molecular Weight 1092 aa, 119 kDa
Observed Molecular Weight145 kDa
GenBank Accession NumberBC136394
Gene Symbol CR2
Gene ID (NCBI) 1380
Conjugate Unconjugated
Form Liquid
Purification MethodAntigen affinity purification
Storage Buffer PBS with 0.02% sodium azide and 50% glycerol pH 7.3.
Storage ConditionsStore at -20°C. Stable for one year after shipment. Aliquoting is unnecessary for -20oC storage. 20ul sizes contain 0.1% BSA.

Background Information

CD21, also known as complement receptor type 2 (CR2), complement C3d receptor, and Epstein-Barr virus receptor, is a transmembrane protein that contains a small cytoplasmic domain, a transmembrane region and an extracellular domain consisting of 15 tandem short consensus repeat sequences (PMID: 6230668; 2551147). It is expressed on B cells, follicular dendritic cells, thymocytes and a subset of peripheral T cells (PMID: 26119182). CD21 binds complement fragments C3d, C3dg and iC3b and acts as a receptor for the Epstein-Barr virus (PMID: 7753047). On B cells, together with CD19 and CD81, CD21 forms a complex that functions as a co-receptor to the BCR (PMID: 7542009). It is involved in B cells activation and functions.


Product Specific Protocols
WB protocol for CD21 antibody 24374-1-APDownload protocol
IHC protocol for CD21 antibody 24374-1-APDownload protocol
Standard Protocols
Click here to view our Standard Protocols



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