Sung S S
J Immunol. 1985 Sep;135(3):1981-6.
Macrophages plated on immune complex-coated substrates of different mouse IgG subclasses were examined for their capacities to phagocytose sheep red blood cells (SRBC) coated with monoclonal antibodies (MAb) of various IgG subclasses. IgG2a-and IgG2b-coated substrates abrogated macrophage phagocytosis of particles coated with any of the four mouse IgG subclasses. These results were confirmed by the use of two MAb of each of the IgG2a and IgG2b subclasses, with one of the MAb specific for dinitrophenyl groups and the others for SRBC. IgG3-coated substrates reduced the macrophage uptake of IgG2a-but not IgG2b-coated particles. Rabbit IgG-coated substrates ablated the uptake of SRBC coated with all mouse IgG subclasses. Resident and thioglycollate-elicited macrophages showed similar phagocytosis reduction when plated on these immune complexes. The phagocytosis of complement-coated particles was not affected by these IgG-coated substrates. Macrophages plated on both IgG2a-and IgG2b-coated substrates showed reduced immunofluorescence staining by an anti-IgG2b Fc receptor (FcR) Ab, 2.4G2 and reduced E(IgG2a) and E(IgG2b) binding. The results show that substrates coated with various IgG subclasses can abrogate phagocytosis mediated by FcR that do not have binding specificity for the substrate-immobilized Fc ligand, and suggest that the three classes of mouse FcR co-modulate.
研究了接种在不同小鼠IgG亚类免疫复合物包被底物上的巨噬细胞对包被有各种IgG亚类单克隆抗体（MAb）的绵羊红细胞（SRBC）的吞噬能力。IgG2a和IgG2b包被的底物消除了巨噬细胞对包被有任何四种小鼠IgG亚类的颗粒的吞噬作用。使用IgG2a和IgG2b亚类的两种MAb证实了这些结果，其中一种MAb对二硝基苯基基团具有特异性，另一种对SRBC具有特异性。IgG3包被的底物减少了巨噬细胞对IgG2a包被但不是IgG2b包被颗粒的摄取。兔IgG包被的底物消除了对包被有所有小鼠IgG亚类的SRBC的摄取。当接种在这些免疫复合物上时，驻留巨噬细胞和巯基乙酸诱导的巨噬细胞显示出相似的吞噬作用降低。补体包被颗粒的吞噬作用不受这些IgG包被底物的影响。接种在IgG2a和IgG2b包被底物上的巨噬细胞通过抗IgG2b Fc受体（FcR）抗体2.4G2显示出免疫荧光染色减少，以及E（IgG2a）和E（IgG2b）结合减少。结果表明，包被有各种IgG亚类的底物可以消除由对底物固定的Fc配体没有结合特异性的FcR介导的吞噬作用，并提示三类小鼠FcR共同调节。
