Differential contribution of three activating IgG Fc receptors (FcgammaRI, FcgammaRIII, and FcgammaRIV) to IgG2a- and IgG2b-induced autoimmune hemolytic anemia in mice.
AuthorsBaudino L, Nimmerjahn F, Azeredo da Silveira S, Martinez-Soria E, Saito T, Carroll M, Ravetch JV, Verbeek JS, Izui S
JournalJ Immunol
PubMed ID18209093
'Murine phagocytes express three different activating IgG FcgammaR: FcgammaRI is specific for IgG2a; FcgammaRIII for IgG1, IgG2a, and IgG2b; and FcgammaRIV for IgG2a and IgG2b. Although the role of FcgammaRIII in IgG1 and IgG2a anti-RBC-induced autoimmune hemolytic anemia (AIHA) is well documented, the contribution of FcgammaRI and FcgammaRIV to the ... More
FcgammaRIV is a mouse IgE receptor that resembles macrophage FcepsilonRI in humans and promotes IgE-induced lung inflammation.
AuthorsMancardi DA, Iannascoli B, Hoos S, England P, Daëron M, Bruhns P
JournalJ Clin Invest
PubMed ID18949059
'FcgammaRIV is a recently identified mouse activating receptor for IgG2a and IgG2b that is expressed on monocytes, macrophages, and neutrophils; herein it is referred to as mFcgammaRIV. Although little is known about mFcgammaRIV, it has been proposed to be the mouse homolog of human FcgammaRIIIA (hFcgammaRIIIA) because of high sequence ... More
IgEb immune complexes activate macrophages through FcgammaRIV binding.
AuthorsHirano M, Davis RS, Fine WD, Nakamura S, Shimizu K, Yagi H, Kato K, Stephan RP, Cooper MD
JournalNat Immunol
PubMed ID17558411
Because functional analysis of Fc receptors (FcRs) relies heavily on mouse models, the identification of another Fcgamma receptor is particularly noteworthy. We demonstrate that FcgammaRIV, identified here as the mouse ortholog of primate FcgammaRIII, required association of the FcR gamma-chain for optimal expression and function on myeloid cells; its signaling ... More
Lymphoma depletion during CD20 immunotherapy in mice is mediated by macrophage FcgammaRI, FcgammaRIII, and FcgammaRIV.
AuthorsMinard-Colin V, Xiu Y, Poe JC, Horikawa M, Magro CM, Hamaguchi Y, Haas KM, Tedder TF
JournalBlood
PubMed ID18495955
Despite the demonstrated clinical efficacy of CD20 monoclonal antibody (mAb) for lymphoma therapy, the in vivo mechanisms of tumor depletion remain controversial and variable. To identify the molecular mechanisms responsible for lymphoma killing by CD20 mAb in a homologous system amenable to mechanistic studies and genetic manipulation, a mouse lymphoma ... More
Critical but overlapping role of FcgammaRIII and FcgammaRIV in activation of murine neutrophils by immobilized immune complexes.
AuthorsJakus Z, Németh T, Verbeek JS, Mócsai A
JournalJ Immunol
PubMed ID18097064
Immune complex-induced activation of neutrophils through cell surface FcRs plays a central role in the pathogenesis of autoimmune inflammatory diseases. These diseases are often modeled using genetically modified mice. However, in contrast to the number of studies on human cells, the identity of FcRs involved in immune complex activation of ... More