| First Author | Yates JL | Year | 2013 |
| Journal | J Immunol | Volume | 191 |
| Issue | 3 | Pages | 1240-9 |
| PubMed ID | 23804710 | Mgi Jnum | J:205726 |
| Mgi Id | MGI:5546297 | Doi | 10.4049/jimmunol.1300062 |
| Citation | Yates JL, et al. (2013) T cell-dependent IgM memory B cells generated during bacterial infection are required for IgG responses to antigen challenge. J Immunol 191(3):1240-9 |
| abstractText | Immunological memory has long considered to be harbored in B cells that express high-affinity class-switched IgG. IgM-positive memory B cells can also be generated following immunization, although their physiological role has been unclear. In this study, we show that bacterial infection elicited a relatively large population of IgM memory B cells that were uniquely identified by their surface expression of CD11c, CD73, and programmed death-ligand 2. The cells lacked expression of cell surface markers typically expressed by germinal center B cells, were CD138 negative, and did not secrete Ab ex vivo. The population was also largely quiescent and accumulated somatic mutations. The IgM memory B cells were located in the region of the splenic marginal zone and were not detected in blood or other secondary lymphoid organs. Generation of the memory cells was CD4 T cell dependent and required IL-21R signaling. In vivo depletion of the IgM memory B cells abrogated the IgG recall responses to specific Ag challenge, demonstrating that the cell population was required for humoral memory, and underwent class-switch recombination following Ag encounter. Our findings demonstrate that T cell-dependent IgM memory B cells can be elicited at high frequency and can play an important role in maintaining long-term immunity during bacterial infection. |
