Molecular characterization of the low-affinity IgE receptor FcεRII/CD23 expressed by human eosinophils
Molecular characterization of the low-affinity IgE receptor FcεRII/CD23 expressed by human eosinophils
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DOI：
10.1093/intimm/10.4.395
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发表时间：
1998-04-01
影响因子：
4.4
通讯作者：
Monique, C
中科院分区：
文献类型：
--
作者：
Abdelilah, SG;Bouchaïb, L;Monique, C
CD23/Fc epsilon RII是一种低亲和力的IgE受体，是一种多能分子，对细胞的激活和增殖、抗原提呈和IgE合成具有多效性。初步研究表明，CD23的表达仅限于B淋巴细胞和巨噬细胞，但现在公认的是更广泛的细胞分布。尽管实验证据表明人嗜酸性粒细胞可以表达具有生物学功能的低亲和力IgE受体Fc epsilon RII/CD23，但到目前为止还没有分子克隆数据报道。原位杂交证实了CD23在嗜酸性粒细胞中的表达，而从文库中提取的人嗜酸性粒细胞cDNA的RT-PCR分析显示CD23的存在，与CD23a和CD23b完全同源。不同嗜酸性粒细胞和白血病细胞株EoL-3经RT-PCR分析均表达CD23a和CD23b亚型，原位RT-PCR证实人嗜酸性粒细胞中存在CD23a和CD23b亚型对应的mRNA，免疫细胞化学显示Fc epsilon RII/CD23和Fc epsilon RI在不同亚群的嗜酸性粒细胞中有不同的表达，Fc epsilon RII/CD23在低密度人群中优先表达。这些结果为人嗜酸粒细胞合成的低亲和力ISE受体(Fc Epsilon RII)与B细胞上表达的CD23分子相同提供了确凿的证据，并且CD23的两个亚型a和b可以由嗜酸性粒细胞表达。
CD23/Fc epsilon RII, the low-affinity receptor for IgE, is a pluripotent molecule with pleiotropic effects on cell activation and proliferation, antigen presentation and IgE synthesis. Initial investigations have suggested that CD23 expression was restricted to B lymphocytes and macrophages, but a much wider cell distribution is now acknowledged. Despite experimental evidence suggesting that human eosinophils could express the low-affinity IgE receptor Fc epsilon RII/CD23 with biological functions, no molecular cloning data have been reported until now. Whereas in situ hybridization confirmed the expression of CD23 mRNA in eosinophils, RT-PCR analysis of human eosinophil cDNA derived from a cDNA library revealed the presence of CD23, totally homologous with the CD23 a and b sequences. Eosinophils from different hypereosinophilic patients as well as the eosinophilic leukemia cell line EoL-3, analyzed by RT-PCR, expressed both CD23 a and b isoforms, In situ RT-PCR confirmed that mRNA corresponding to CD23 a and b isoforms was detected in human eosinophils, Finally, immunocytochemistry allowed us to show a differential expression of Fc epsilon RII/CD23 and Fc epsilon RI by subpopulations of eosinophils, with a preferential expression of Fc epsilon RII/CD23 in the hypodense population. These results provide definitive evidence that the low-affinity ISE receptor (Fc epsilon RII) synthesized by human eosinophils is identical to the CD23 molecule expressed on B cells, and that the two CD23 isoforms a and b can be expressed by eosinophils.