CD21 Polyclonal antibody

CD21 Polyclonal Antibody for IF, IHC, ELISA

Host / Isotype

Rabbit / IgG







Cat no : 28206-1-AP


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

Tested Applications

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
Positive IF detected inhuman tonsillitis tissue

Recommended dilution

Immunohistochemistry (IHC)IHC : 1:50-1:500
Immunofluorescence (IF)IF : 1:50-1:500
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

28206-1-AP targets CD21 in IF, IHC, ELISA applications and shows reactivity with Human samples.

Tested Reactivity Human
Host / Isotype Rabbit / IgG
Class Polyclonal
Type Antibody
Immunogen CD21 fusion protein Ag27971
Full Name complement component (3d/Epstein Barr virus) receptor 2
Calculated Molecular Weight 1092 aa, 119 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
IHC protocol for CD21 antibody 28206-1-APDownload protocol
IF protocol for CD21 antibody 28206-1-APDownload protocol
Standard Protocols
Click here to view our Standard Protocols