IgA production without mu or delta chain expression in developing B cells.
IgA production without mu or delta chain expression in developing B cells.
复制标题
发育中的 B 细胞中不表达 mu 或 delta 链的 IgA 产生。
作者：
A. Macpherson;A. Lamarre;K. McCoy;G. Harriman;B. Odermatt;G. Dougan;H. Hengartner;R. Zinkernagel
在B细胞个体发育早期的表面、膜结合的免疫球蛋白M（IgM）或IgD表达被认为是哺乳动物中抗体产生细胞的分化所必需的;仅在IgM+ B细胞中重链基因座重排以表达其他类别的抗体。我们在这里表明，伊加选择性地表达在muMT小鼠，缺乏IgM或IgD表达，并有一个前B细胞发育阻滞。muMT伊加结合肠道细菌的蛋白质，并且由沙门氏菌感染弱诱导，尽管不是通过常规免疫。这种muMT伊加途径需要脾外外周淋巴组织，并且可能是一种进化上原始的系统，其中未成熟的B细胞在外周部位转换为伊加产生。
Surface, membrane-bound, immunoglobulin M (IgM) or IgD expression early in B cell ontogeny is considered essential for the differentiation of antibody-producing cells in mammals; only in IgM+ B cells is the heavy chain locus rearranged to express antibodies of other classes. We show here that IgA is selectively expressed in muMT mice, which lack IgM or IgD expression and have a pro-B cell developmental block. muMT IgA binds proteins of commensal intestinal bacteria and is weakly induced by Salmonella infection, although not through conventional immunization. This muMT IgA pathway requires extrasplenic peripheral lymphoid tissues and may be an evolutionarily primitive system in which immature B cells switch to IgA production at peripheral sites.