• Species Reactivity

  Human

• Specificity

  Detects human FCRL1/FcRH1 in direct ELISAs and Western blots. In Western blots, no cross-reactivity with recombinant human (rh) FCRL2, 3, 4, or 5 is observed.

• Source

  Monoclonal Mouse IgG    ₁ Clone # 282415

• Purification

  Protein A or G purified from hybridoma culture supernatant

• Immunogen

  Mouse myeloma cell line NS0-derived recombinant human FCRL1/FcRH1    
  Ala17-His304    
  Accession # Q96LA6

• Formulation

  Supplied in a saline solution containing BSA and Sodium Azide.

• Label

  Phycoerythrin

Applications

• 
  

  Recommended    
  Concentration

  Sample

• Flow Cytometry

  10 µL/10    ⁶ cells

  See below

• 
  

Please Note: Optimal dilutions should be determined by each laboratory for each application.  are available in the Technical Information section on our website.

Data Examples

Preparation and Storage

• Shipping

  The product is shipped with polar packs. Upon receipt, store it immediately at the temperature recommended below.

• Stability & Storage

  Protect from light.    Do not freeze.    

• 12 months from date of receipt, 2 to 8 °C as supplied.

Background: FCRL1/FcRH1

Fc Receptor-Like 1 (FCRL1), also known as FcRH1, and IRTA5, is an approximately 50 kDa protein with sequence homology to classical Fc receptors. The type 1 transmembrane FCRL proteins contain from three to nine immunoglobulin-like domains. They are differentially expressed within the B cell lineage and can either promote or inhibit B cell proliferation and activation (1, 2). According to R&D Systems testing, FCRL1 binds to purified human IgG. Mature human FCRL1 consists of a 291 amino acid (aa) extracellular domain (ECD) with three Ig-like domains, a 21 aa transmembrane segment, and a 101 aa cytoplasmic domain with two immunotyrosine activation motifs (ITIMs) (3, 4). A charged glutamic acid within the transmembrane segment may mediate association with other signaling proteins. Alternative splicing may generate an isoform that lacks the transmembrane segment and an isoform that largely consists of the first two Ig-like domains (5). Mouse FCRL1 contains only two Ig-like domains, but it shares 62% aa sequence identity with homologous regions of the human FCRL1 ECD. FCRL1 is expressed on pre-B cells and naive B cells (6, 7). It is down‑regulated upon B cell activation but up‑regulated on memory B cells (6, 8). FCRL1 is expressed on many B cell lymphoma and leukemia tumor cells with the exception of B cell acute lymphoblastic leukemia (9‑11). Antibody crosslinking of FCRL1 triggers its tyrosine phosphorylation and augments B cell proliferation induced by the B cell receptor (6).

• References:

1. Davis, R.S. et al. (2007) Annu. Rev. Immunol. 25:525.

2. Maltais, L.J. et al. (2006) Nat. Immunol. 7:431.

3. Miller, I. et al. (2002) Blood 99:2662.

4. Davis, R.S. et al. (2001) Proc. Natl. Acad. Sci. 98:9772.

5. Accession # Q96LA6.

6. Leu, C.-M. et al. (2005) Blood 105:1121.

7. Li, F.J. et al. (2008) Blood 112:179.

8. Polson, A.G. et al. (2006) Int. Immunol. 18:1363.

9. Du, X. et al. (2008) Blood 111:338.

10. Kazemi, T. et al. (2008) Int. J. Cancer 123:2113.

11. Kazemi, T. et al. (2009) Cancer Immunol. Immunother. 58:989.

• Long Name:

  Fc Receptor-like 1

• Entrez Gene IDs:

  115350 (Human); 229499 (Mouse); 680665 (Rat)

• Alternate Names:

  BXMH1; CD307a antigen; CD307a; Fc receptor homolog 1; Fc receptor-like 1; FcRH1; FCRH1DKFZp667O1421; FCRL1; FcR-like protein 1; hIFGP1; IFGP family protein 1; IFGP1; IFGP1Fc receptor-like protein 1; Immune receptor translocation-associated protein 5; IRTA5; IRTA5immunoglobulin superfamily Fc receptor, gp42