Haber P L, Mestecky J
Cell Immunol. 1985 Apr 1;91(2):515-9. doi: 10.1016/0008-8749(85)90249-7.
Previous studies have demonstrated that J chain is expressed not only in cells that produce polymeric immunoglobulins, but also in those engaged in synthesis of monomers including IgG and IgD. The presence of J chain in these cells suggested that its role may not be restricted to the formation of polymers. For the present study, fluorochrome-labeled polyclonal anti-J-chain and monoclonal antibodies to IgG subclasses were used to determine the distribution of J chain in IgG plasma cells from normal human tissues and from pokeweed mitogen (PWM)-stimulated human peripheral blood lymphocytes. The results indicate that J chain is not equally distributed among cells producing different IgG subclasses. The percentages of PWM-stimulated cells containing J chain were: 22 +/- 5 (SE) for IgG1, 49 +/- 6 for IgG2, 17 +/- 7 for IgG3, and 64 +/- 11 for IgG4. Examination of sections of various human lymphoid tissues revealed that the frequency of IgG cells that coexpressed J chain was lower than that observed in the PWM system and displayed variable distribution among IgG subclasses. The frequency of J-chain expression in IgG-producing cells may be related to the degree of cellular maturation and may differ according to the origin of cells.
以往的研究表明，J链不仅在产生聚合免疫球蛋白的细胞中表达，而且在参与合成包括IgG和IgD在内的单体的细胞中也有表达。这些细胞中J链的存在表明其作用可能不限于聚合物的形成。在本研究中，使用荧光染料标记的多克隆抗J链抗体和针对IgG亚类的单克隆抗体来确定J链在来自正常人组织和商陆有丝分裂原（PWM）刺激的人外周血淋巴细胞的IgG浆细胞中的分布。结果表明，J链在产生不同IgG亚类的细胞中分布不均。PWM刺激的含J链细胞的百分比分别为：IgG1为22±5（SE），IgG2为49±6，IgG3为17±7，IgG4为64±11。对各种人类淋巴组织切片的检查显示，共表达J链的IgG细胞的频率低于在PWM系统中观察到的频率，并且在IgG亚类之间表现出可变分布。产生IgG的细胞中J链表达的频率可能与细胞成熟程度有关，并且可能因细胞来源而异。
