Western blot shows lysates of human spleen tissue. PVDF Membrane was probed with 2 µg/mL of Mouse Anti-Human CD21 Monoclonal Antibody (Catalog # MAB4909) followed by HRP-conjugated Anti-Mouse IgG Secondary Antibody (Catalog # HAF007). A specific band was detected for CD21 at approximately 145 kDa (as indicated). This experiment was conducted under non-reducing conditions and using Immunoblot Buffer Group 1. This antibody is recommended to be used under non-reducing conditions only.

Detection of CD21 in Human PBMCs by Flow Cytometry.

Human peripheral blood mononuclear cells (PBMCs) were stained with Mouse Anti-Human CD19 PE-conjugated Monoclonal Antibody (Catalog # FAB4867P) and either (A) Mouse Anti-Human CD21 Monoclonal Antibody (Catalog # MAB4909) or (B) Mouse IgG₁Isotype Control (Catalog # MAB002) followed by Allophycocyanin-conjugated Anti-Mouse IgG Secondary Antibody (Catalog # F0101B).

Applications for Human CD21 Antibody

Application

Recommended Usage

CyTOF-ready

Ready to be labeled using established conjugation methods. No BSA or other carrier proteins that could interfere with conjugation.

Flow Cytometry

0.25 µg/10⁶ cells
Sample: Human peripheral blood mononuclear cells (PBMCs)

Western Blot

2 µg/mL
Sample: Human spleen tissue, under non-reducing conditions only

Formulation, Preparation, and Storage

Purification

Protein A or G purified from hybridoma culture supernatant

Reconstitution

Reconstitute at 0.5 mg/mL in sterile PBS. For liquid material, refer to CoA for concentration.

Formulation

Lyophilized from a 0.2 μm filtered solution in PBS with Trehalose. *Small pack size (SP) is supplied either lyophilized or as a 0.2 µm filtered solution in PBS.

Shipping

Lyophilized product is shipped at ambient temperature. Liquid small pack size (-SP) is shipped with polar packs. Upon receipt, store immediately at the temperature recommended below.

Stability & Storage

Use a manual defrost freezer and avoid repeated freeze-thaw cycles.

12 months from date of receipt, -20 to -70 °C as supplied.
1 month, 2 to 8 °C under sterile conditions after reconstitution.
6 months, -20 to -70 °C under sterile conditions after reconstitution.

Background: CD21

CD21 (also called EBV receptor or CR2) is a 145 kDa 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 1013 amino acids (aa) in length. It is a type I transmembrane (TM) protein that contains a 951 aa extracellular domain (ECD) (aa 21-971) and a short 34 aa cytoplasmic tail. The ECD exhibits fifteen 60 aa SUSHI repeats. Soluble CD21 can be generated by cleavage near the TM domain. One potential splice variant shows a deletion of aa 847‑908, while another shows an insertion of 59 aa after Lys659. The ECD of human CD21 shares 71% aa identity with mouse CD21 ECD.

Alternate Names

C3DR, CD21, CR2

Entrez Gene IDs

1380 (Human); 12902 (Mouse); 289395 (Rat)

Gene Symbol

CR2

UniProt

P20023 (Human)

Additional CD21 Products

Product Documents for Human CD21 Antibody

Product Datasheets

Download Product Datasheets

COA

SDS

Download SDS

Product Specific Notices for Human CD21 Antibody

For research use only

Citations
Reviews

Calculators
Flow Cytometry

Human CD21 Antibody

R&D Systems, part of Bio-Techne | Catalog # MAB4909

Key Product Details

Species Reactivity

Validated:

Cited:

Applications

Validated:

Cited:

Label

Antibody Source

View all CD21 Antibodies »

Product Specifications

Immunogen

Specificity

Clonality

Host

Isotype

Scientific Data Images for Human CD21 Antibody

Detection of Human CD21 by Western Blot.