First Author | Kaji T | Year | 2013 |
Journal | Int Immunol | Volume | 25 |
Issue | 12 | Pages | 683-95 |
PubMed ID | 24021876 | Mgi Jnum | J:203115 |
Mgi Id | MGI:5525006 | Doi | 10.1093/intimm/dxt030 |
Citation | Kaji T, et al. (2013) Both mutated and unmutated memory B cells accumulate mutations in the course of the secondary response and develop a new antibody repertoire optimally adapted to the secondary stimulus. Int Immunol 25(12):683-95 |
abstractText | High-affinity memory B cells are preferentially selected during secondary responses and rapidly differentiate into antibody-producing cells. However, it remains unknown whether only high-affinity, mutated memory B cells simply expand to dominate the secondary response or if in fact memory B cells with a diverse VH repertoire, including those with no mutations, accumulate somatic mutations to create a new repertoire through the process of affinity maturation. In this report, we took a new approach to address this question by analyzing the VH gene repertoire of IgG1(+) memory B cells before and after antigen re-exposure in a host unable to generate IgG(+) B cells. We show here that both mutated and unmutated IgG1(+) memory B cells respond to secondary challenge and expand while accumulating somatic mutations in their VH genes in a stepwise manner. Both types of memory cells subsequently established a VH gene repertoire dominated by two major clonotypes, which are distinct from the original repertoire before antigen re-exposure. In addition, heavily mutated memory B cells were excluded from the secondary repertoire. Thus, both mutated and unmutated IgG1(+) memory cells equally contribute to establish a new antibody repertoire through a dynamic process of mutation and selection, becoming optimally adapted to the recall challenge. |