Monroe J G, Blank K J, Owen C S, Sykes N
Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, Philadelphia 19104.
Mol Immunol. 1989 Jul;26(7):593-9. doi: 10.1016/0161-5890(89)90041-2.
A novel murine B lymphoma expressing membrane-associated IgA was isolated and used to compare mechanisms of signal transduction by sIgM and sIgA. Like other isotypes so far studied, crosslinking of sIgA by anti-immunoglobulin antibodies stimulates hydrolysis of inositol phospholipids and causes elevation of intracellular free calcium. Furthermore, signals generated through sIgA are coupled to elevation of c-fos proto-oncogene expression. Coupling appears to be through the protein kinase C rather than through the Ca2+ component of sIg signalling as phorbol diester, but the Ca2+ ionophore cannot mediate this effect. Thus these results, coupled with those from earlier studies, show that early signal transduction through surface immunoglobulin appears to be similar regardless of the particular isotype involved in binding ligand.
分离出一种表达膜相关IgA的新型小鼠B淋巴瘤，并用于比较sIgM和sIgA的信号转导机制。与迄今为止研究的其他同种型一样，抗免疫球蛋白抗体对sIgA的交联刺激肌醇磷脂的水解，并导致细胞内游离钙升高。此外，通过sIgA产生的信号与c-fos原癌基因表达的升高相关联。这种关联似乎是通过蛋白激酶C，而不是通过sIg信号传导的Ca2+成分，因为佛波二酯可以，但Ca2+离子载体不能介导这种效应。因此，这些结果与早期研究的结果相结合，表明无论与配体结合的是哪种特定同种型，通过表面免疫球蛋白的早期信号转导似乎都是相似的。
