Rothstein T L, Kolber D L, Murphy T P, Cohen D P
Department of Medicine, Boston University Medical Center, MA 02118.
J Immunol. 1991 Dec 1;147(11):3728-35.
The signals required to induce S phase entry in murine splenic B cells were found to be altered by prolonged treatment with low doses of anti-Ig antibody. Whereas fresh splenic B cells are stimulated by the combination of a phorbol ester protein kinase C agonist plus a calcium ionophore, anti-Ig-treated splenic B cells were stimulated by phorbol ester alone, in the absence of a comitogen. The majority of these phorbol ester responsive B cells expressed CD5. The phorbol ester responses of anti-Ig-treated splenic B cells paralleled those previously reported for untreated peritoneal CD5+ B cells in a number of respects: responses were not idiosyncratic to phorbol esters but occurred with nonphorbol protein kinase C agonists; phorbol ester responses were enhanced by IL-4; and, phorbol ester responses occurred rapidly and were greater at 24 than at 48 h. However, the effect of agents that act to raise intracellular levels of cAMP distinguished between anti-Ig-treated splenic B cells and untreated peritoneal B cells in that the phorbol ester responses of the former were enhanced whereas the responses of the latter were inhibited. The present results add a functional dimension to the phenotypic similarity between splenic B cells treated with anti-Ig and resident peritoneal B cells that constitutively express CD5; however, some differences in behavior were noted.
研究发现，用低剂量抗Ig抗体长期处理会改变诱导小鼠脾B细胞进入S期所需的信号。新鲜脾B细胞可被佛波酯（一种蛋白激酶C激动剂）加钙离子载体共同刺激，而经抗Ig处理的脾B细胞在无共刺激原的情况下仅被佛波酯刺激。这些对佛波酯有反应的B细胞大多数表达CD5。在许多方面，经抗Ig处理的脾B细胞对佛波酯的反应与先前报道的未经处理的腹膜CD5 + B细胞相似：反应并非佛波酯所特有，非佛波蛋白激酶C激动剂也可引发；IL-4可增强对佛波酯的反应；并且，对佛波酯的反应迅速，24小时时比48小时时更强。然而，提高细胞内cAMP水平的药物的作用在经抗Ig处理的脾B细胞和未经处理的腹膜B细胞之间存在差异，前者对佛波酯的反应增强，而后者的反应受到抑制。目前的结果为经抗Ig处理的脾B细胞与组成性表达CD5的驻留腹膜B细胞之间的表型相似性增加了功能层面的内容；然而，也注意到了一些行为上的差异。
