Abcam, ab227668, Anti-CD21 antibody [SP199]

Size: 100µL / 500µL / 1mL
Rabbit Recombinant Monoclonal CD21 antibody. Suitable for Flow Cyt (Intra), WB, IHC-P and reacts with Human samples. Cited in 2 publications.
Key facts
Host species:Rabbit,
Clonality:Monoclonal,
Clone number:SP199,
Isotype:IgG,
Carrier free:No,
Reacts with:Human,
Applications:WB, Flow Cyt (Intra), IHC-PSee reactivity dataSee the reactivity data table below for information on validated species and application combinations.,
Immunogen:The exact immunogen used to generate this antibody is proprietary information.

Properties and Storage Information:
Form-Liquid, Purification technique-Affinity purification Protein A/G, Purification notes-Purified from TCS by protein A/G., Storage buffer-pH: 7.6Preservative: 0.1% Sodium azideConstituents: PBS, 1% BSA, Shipped at conditions-Blue Ice, Appropriate short-term storage duration-1-2 weeks, Appropriate short-term storage conditions-+4°C, Appropriate long-term storage conditions--20°C, Aliquoting information-Upon delivery aliquot, Storage information-Avoid freeze / thaw cycle

Supplementary Information:
This supplementary information is collated from multiple sources and compiled automatically.
CD21 also known as complement receptor type 2 (CR2) or BU32 is a protein primarily expressed on the surface of B cells and some T cells. It functions as a receptor for complement component C3d EBV (Epstein-Barr Virus) and IFN-α. CD21 weighs approximately 145 kDa and belongs to the membrane protein family. Detection of CD21 can be done via immunohistochemistry (IHC) and blood tests. This marker is valuable for identifying cell populations that have roles in immune responses.
Biological function summary
Complement receptor type 2 is key in the immune system by facilitating B cell activation and proliferation. CD21 forms complexes with CD19 and CD81 increasing the sensitivity of B cells to antigens. This interaction enhances signal transduction enabling B lymphocytes to respond effectively to pathogens. The protein also plays a role in regulating immune tolerance and maintaining humoral immunity being important not only in immune defense but also in preventing autoimmunity.
Pathways
CD21 interacts with complement activation and immune response pathways. It connects with CD19 in a pivotal role where it further amplifies signaling in B lymphocytes. This interaction strengthens the downstream signaling of BCR (B cell receptor) important for antibody production. CD21 contributes to bridging the innate and adaptive immunological pathways by engaging components like C3d.
CD21 shows significant relevance in systemic lupus erythematosus (SLE) and some B cell lymphomas. Deficiencies or mutations in CD21 can lead to defective immune responses and increased susceptibility to autoimmune conditions such as SLE where CD19 is also implicated. Furthermore in Epstein-Barr Virus infections CD21 serves as an entry receptor facilitating pathogen establishment which can result in chronic conditions or even malignancies.