González-Fernández A, Gilmore D, Milstein C
MRC, Laboratory of Molecular Biology, Cambridge.
Eur J Immunol. 1994 Nov;24(11):2918-21. doi: 10.1002/eji.1830241151.
Somatic hypermutation of immunoglobulin genes and the generation of memory B cells seems to take place in germinal centers, which are chronically present in Peyer's patches. Age-associated changes in the germinal center B cell compartment of Peyer's patches and in the mutations of a kappa light chain transgene were analyzed in unimmunized mice. Somatic mutations accumulate in germinal center B cells slowly and continuously to reach an apparent plateau when the animals are around 5 months old. In contrast, the proportion of germinal center B cells reaches a maximum in very young mice (about 2 months old) and decreases progressively thereafter. These results suggest that the highly mutated B cells in older mice arise by the successive accumulation of mutations in memory cells. The data also show that the optimum time for the analysis of hypermutation of transgenes in Peyer's patches is when the mice are about 5 months old.
免疫球蛋白基因的体细胞超突变和记忆B细胞的产生似乎发生在生发中心，生发中心长期存在于派尔集合淋巴结中。在未免疫的小鼠中，分析了派尔集合淋巴结生发中心B细胞区室的年龄相关变化以及κ轻链转基因的突变情况。体细胞突变在生发中心B细胞中缓慢而持续地积累，当动物约5个月大时达到明显的稳定状态。相比之下，生发中心B细胞的比例在非常年幼的小鼠（约2个月大）中达到最大值，此后逐渐下降。这些结果表明，老年小鼠中高度突变的B细胞是由记忆细胞中突变的连续积累产生的。数据还表明，分析派尔集合淋巴结中转基因超突变的最佳时间是小鼠约5个月大时。
