| First Author | Boneparth A | Year | 2015 |
| Journal | PLoS One | Volume | 10 |
| Issue | 3 | Pages | e0119925 |
| PubMed ID | 25794167 | Mgi Jnum | J:229194 |
| Mgi Id | MGI:5751028 | Doi | 10.1371/journal.pone.0119925 |
| Citation | Boneparth A, et al. (2015) TLR7 influences germinal center selection in murine SLE. PLoS One 10(3):e0119925 |
| abstractText | TLR7 enhances germinal center maturation and migration of B cells to the dark zone where proliferation and somatic hypermutation occur. Our goal was to determine how Tlr7 dose influences selection of the autoreactive B cell repertoire in NZW/BXSB. Yaa mice bearing the site-directed heavy chain transgene 3H9 that encodes for the TLR7 regulated anti-CL response. To create a physiologic setting in which autoreactive B cells compete for survival with non-autoreactive B cells, we generated bone marrow chimeras in which disease onset occurred with similar kinetics and the transferred 3H9+ female non-Yaa, male Yaa or male TLR7(-/Yaa) cells could be easily identified by positivity for GFP. Deletion of 3H9 B cells occurred in the bone marrow and the remaining 3H9 follicular B cells manifested a decrease in surface IgM. Although there were differences in the naive repertoire between the chimeras it was not possible to distinguish a clear pattern of selection against lupus related autoreactivity in TLR7(-/Yaa) or female chimeras. By contrast, preferential expansion of 3H9+ B cells occurred in the germinal centers of male Yaa chimeras. In addition, although all chimeras preferentially selected 3H9/Vkappa5 encoded B cells into the germinal center and plasma cell compartments, 3H9 male Yaa chimeras had a more diverse repertoire and positively selected the 3H9/Vkappa5-48/Jkappa4 pair that confers high affinity anti-cardiolipin activity. We were unable to demonstrate a consistent effect of Tlr7 dose or Yaa on somatic mutations. Our data show that TLR7 excess influences the selection, expansion and diversification of B cells in the germinal center, independent of other genes in the Yaa locus. |
