%0 Journal Article
%1 Viertlboeck:2007:Proc-Natl-Acad-Sci-U-S-A:17606923
%A Viertlboeck, B. C.
%A Schweinsberg, S.
%A Hanczaruk, M. A.
%A Schmitt, R.
%A Pasquier, L. Du
%A Herberg, F. W.
%A Göbel, T. W.
%D 2007
%J Proc Natl Acad Sci U S A
%K herberg myown
%N 28
%P 11718-11723
%T The chicken leukocyte receptor complex encodes a primordial, activating, high-affinity IgY Fc receptor
%U http://www.ncbi.nlm.nih.gov/pubmed/17606923
%V 104
%X Fc receptors are key players of the immune system that link the fine specificity of immunoglobulins and innate effector responses. Here, we describe a nonmammalian Fcgamma receptor, CHIR-AB1, a member of the leukocyte receptor complex, that binds IgY with high affinity with its single Ig domain. It is expressed on immature and mature B lymphocytes, monocytes, macrophages, and natural killer cells and harbors motifs of activating and inhibitory Fc receptors. In the absence of FcepsilonRIgamma, CHIR-AB1 can be expressed on B cells but cross-linking does not induce intracellular calcium release. In contrast, cells expressing CHIR-AB1 and FcepsilonRIgamma are triggered to release intracellular calcium upon stimulation with heat-aggregated IgY. CHIR-AB1 thus represents a primordial Fc receptor that combines features of different mammalian counterparts.