Anti-FcgRIV (CD16-2) Antibody, clone 9E9

Transmembrane receptor CD16-2 (UniProt: Q8R477; also known as CD16-2, Fcgr4, FcgRIV, Fc gammaRIV, FcgammaRIV, Fcgr3a, CD16-2, Transmembrane receptor CD16-2) is encoded by the Fcgr4 (also known as Fcgr3a, Fcrl3) gene (Gene ID: 245256) in murine species. Murine species express three classes of activating IgG Fc receptors, the high affinity receptor FcgRI, the low affinity receptor FcgRIII, and the FcgRIV or CD16-2. CD16-2, a novel mouse receptor that displays significant homology to CD16/FcgRIII. It is a receptor for soluble IgG2a and 2b complexes, but not necessarily for cellular bound IgG2a. CD16-2 is expressed in peripheral blood leukocytes and in spleen, thymus, colon, and intestine. Similar to other activating receptors, CD16-2 possesses a charged residue within its transmembrane domain that is necessary for association with an ITAM (immunoreceptor tyrosine-based activation motif) bearing accessory protein. Both CD16-2 (FcgRIV) and FcgRIII are considered to be essential for mediating type II and type III autoimmune responses via FcRc-LAT-dependent generation of C5a. However, FcgRIII-deficient mice display compensatory enhanced CD16-2 expression that offers protection from lung inflammation and exhibit reduced sensitivity to IgG2a/b-mediated hemolytic anemia. Ref.: Syed, S.N., et al (2009). Eur. J. Immunol. 39(12): 3343-3356; Mechetina, L.V., et al. (2002). Immunogenetics 54(7): 463-468.

The previously assigned protein identifier Q8R477 has been merged into A0A0B4J1G0. Full details can be found on the UniProt database.

Clone 9E9 immunostained murine macrophages, neutrophils, dendritic cells, but not FcgRIII-expressing NK cells. Clone 9E9 also stained a FcgRIV-negative, B220-positive peripheral blood cell population (Syed, S.N., et al. (2009). Eur. J. Immunol. 39(12):3343-3356).

Recombinant mouse FcgRIV extracellular domain fused to mouse IgG1 Fc fragment (Nimmerjahn, F., et al. (2005). Immunity. 23(1):41-51).

Flow Cytometry Analysis: 20 µg/mL from a representative lot, when added prior to APC-conjugated 9E9, blocked the staining of FcgRIV-positive granulocytes and monocytes by APC-conjugated 9E9 (Courtesy of Jeanette Leusen, Ph.D, University Medical Center, Utrecht, Netherlands).

Flow Cytometry Analysis: A representative lot detected FcgRIV-positive granulocytes and monocytes from wild-type, but not Fcgr4-knockout mice (Nimmerjahn, F., et al. (2010). Proc. Natl. Acad. Sci. U. S. A. 107(45):19396-19401).

Flow Cytometry Analysis: A representative lot, pre-conjugated with Alexa Fluor^™ 647, immunostained murine macrophages, neutrophils, dendritic cells, but not FcgRIII-expressing NK cells. Clone 9E9 also stained a FcgRIV-negative, B220-positive peripheral blood cell population (Syed, S.N., et al. (2009). Eur. J. Immunol. 39(12):3343-3356).

Neutralizing Analysis: A representative lot, when administered (400-500 µg) via i.v. injection prior to anti-RBC 34-3C-IgG2b (50 µg) i.p. injection, prevented anemia (RBC depletion) induction by 34-3C-IgG2b. Clone 9E9 also prevented immunocomplex (IC) challenge-induced alveolar RBC & PMN infiltration in IC-sensitized mice (Syed, S.N., et al. (2009). Eur. J. Immunol. 39(12):3343-3356).

Neutralizing Analysis: A representative lot suppressed both wild-type and Fcgr1-/Fcgr3-knockout mouse peritoneal macrophages-mediated phogocytosis of red blood cells (RBCs) opsonized with anti-RBC IgG2b, but not anti-RBC IgG2a (Syed, S.N., et al. (2009). Eur. J. Immunol. 39(12):3343-3356).

Neutralizing Analysis: A representative lot prevented immune complex binding-induced activation of Fcgr3-deficient mouse neutrophils (Jakus, Z., et al. (2008). J. Immunol. 180(1):618-629).

Neutralizing Analysis: A representative lot, when administered (200 µg) via i.v. injection 30 min prior to anti-platelet 6A6-IgG2a Fc fusion (3.5 µg) injection, reduced the extend of thrombocytopenia (platelet depletion) induction by 6A6-IgG2a (Nimmerjahn, F., et al. (2005). Immunity. 23(1):41-51).

This armenian hamster monoclonal Anti-FcgRIV (CD16-2) Antibody, clone 9E9, Cat. No. MABF853 is validated for use in Flow Cytometry and Neutralization.

Evaluated by Flow Cytometry in RAW264.7 cells.

Flow Cytometry Analysis: 0.1 µg of this antibody detected FcgRIV on the surface of one million RAW264.7 murine macrophages.

28.39/28.37/28.38 kDa (UniProt Q3TC44/Q8R2R4/Q8R477) calculated.

Format: Purified

Purified armenian hamster IgG in PBS without azide.

Concentration: Please refer to lot specific datasheet.

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