McIntyre T M, Holmes K L, Steinberg A D, Kastner D L
Cellular Immunology Section, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD 20892.
J Immunol. 1991 May 15;146(10):3639-45.
We used in situ hybridization to study Ig mRNA levels in murine peritoneal and splenic B cells. Ig mRNA production fell into three distinct groups: low, intermediate, and high. Splenic B cells primarily exhibited low levels characteristic of resting B cells or high Ig mRNA levels characteristic of plasma cells. In contrast, a significant fraction of peritoneal B cells exhibited intermediate Ig mRNA levels. Intermediate Ig mRNA was T cell dependent in that congenic nu/nu mice had far fewer peritoneal cells expressing the intermediate Ig message than their wild type counterparts. CD5+ CD11b+ IgMbright+ peritoneal B cells were found to be mainly responsible for the production of intermediate Ig mRNA levels. The peritoneal CD5- CD11b+ IgMbright+ "sister" B cell subpopulation contained a lower percentage of intermediate Ig mRNA-producing B cells. CD5-CD11b-IgMdull+ "conventional" B cells produced negligible levels of Ig mRNA, comparable to those of unfractionated splenic B cells. Northern analysis showed that the majority of Ig mRNA expressed in the peritoneum is of the membrane rather than the secreted form. Consistent with that result, in short-term culture, peritoneal cells showed markedly less Ig secretion than did spleen cells. These studies describe novel Ig mRNA expression by peritoneal B cells and emphasize that within the peritoneal cavity, B cells do not tend to become antibody-secreting cells.
我们采用原位杂交技术研究小鼠腹膜和脾脏B细胞中的Ig mRNA水平。Ig mRNA的产生分为三个不同的组：低、中、高。脾脏B细胞主要表现出静止B细胞的低水平特征或浆细胞的高Ig mRNA水平特征。相比之下，相当一部分腹膜B细胞表现出中等水平的Ig mRNA。中等水平的Ig mRNA依赖于T细胞，因为同基因nu/nu小鼠表达中等水平Ig信息的腹膜细胞比野生型对应物少得多。发现CD5+CD11b+IgMbright+腹膜B细胞主要负责产生中等水平的Ig mRNA。腹膜CD5-CD11b+IgMbright+“姐妹”B细胞亚群中产生中等水平Ig mRNA的B细胞百分比更低。CD5-CD11b-IgMdull+“传统”B细胞产生的Ig mRNA水平可忽略不计，与未分离的脾脏B细胞相当。Northern分析表明，腹膜中表达的大多数Ig mRNA是膜形式而非分泌形式。与该结果一致，在短期培养中，腹膜细胞的Ig分泌明显少于脾脏细胞。这些研究描述了腹膜B细胞新的Ig mRNA表达，并强调在腹膜腔内，B细胞不易成为抗体分泌细胞。
