Vaickus L, Robinson M, Lynch R G
Department of Medicine, University of Iowa Hospitals and Clinics, Iowa City.
Clin Immunol Immunopathol. 1988 Apr;47(1):106-19. doi: 10.1016/0090-1229(88)90149-3.
Fluorochrome-labeled, human immunoglobulins (Igs) were used to characterize peripheral blood mononuclear cell (PBMC) subsets that had Fc receptors (FcRs) for the three major isotype classes, IgG, IgA and IgM. Relatively high concentrations of these Igs were needed to saturate FcRs. However, by a number of criteria, competition assays in particular, isotype-specific FcR binding was shown. In vivo bound Ig was directly measured by anti-Fc class-specific F(ab)2 antibodies. With the exception of monocytes, where a mean of 19% had in vivo bound IgG, only small percentages of other PBMC subsets had any type of in vivo bound Ig. Studies done on a large group of normal individuals revealed that approximately 27% of all PBMCs had gamma, 24% alpha, and 23% microFcRs. Dual fluorescence assays were performed to determine the gamma, alpha, and microFcR status on T, B, NK cells and on monocytes. The majority of staining for gamma, alpha, and microFcRs was accounted for by the numerically largest subfraction, the T cells. However, when FcR status was determined for each subset virtually all had either gamma, alpha, or microFcRs--94% of CD2+, 98% of CD4+, 73% of CD8+, 100% of CD19+, 100% of CDw19+, 92% of Leu 7+, and 61% of Leu 11+ cells. All three FcRs were expressed within each subset. Of interest, a small percentage of unfractionated and monocyte-depleted PBMCs coexpressed one of three pairs of FcRs, either alpha and gamma, alpha and mu, or mu and gamma.
用荧光染料标记的人免疫球蛋白（Ig）来鉴定外周血单个核细胞（PBMC）亚群，这些亚群具有针对三种主要同种型类别IgG、IgA和IgM的Fc受体（FcR）。需要相对高浓度的这些Ig来饱和FcR。然而，通过多种标准，特别是竞争试验，显示了同种型特异性FcR结合。体内结合的Ig通过抗Fc类特异性F(ab)2抗体直接测量。除单核细胞外，平均19%的单核细胞有体内结合的IgG，其他PBMC亚群只有小比例的细胞有任何类型的体内结合Ig。对一大组正常个体的研究表明，所有PBMC中约27%有γFcR，24%有αFcR，23%有μFcR。进行双荧光试验以确定T细胞、B细胞、NK细胞和单核细胞上的γ、α和μFcR状态。γ、α和μFcR的大部分染色由数量上最大的亚群T细胞引起。然而，当确定每个亚群的FcR状态时，几乎所有细胞都有γ、α或μFcR——94%的CD2+细胞、98%的CD4+细胞、73%的CD8+细胞、100%的CD19+细胞、100%的CDw19+细胞、92%的Leu 7+细胞和61%的Leu 11+细胞。所有三种FcR在每个亚群中均有表达。有趣的是，一小部分未分级和去除单核细胞的PBMC共表达三对FcR中的一对，即α和γ、α和μ或μ和γ。
