| First Author | Contreras CM | Year | 2007 |
| Journal | Mol Immunol | Volume | 44 |
| Issue | 10 | Pages | 2719-28 |
| PubMed ID | 17207856 | Mgi Jnum | J:118704 |
| Mgi Id | MGI:3700124 | Doi | 10.1016/j.molimm.2006.11.023 |
| Citation | Contreras CM, et al. (2007) Btk regulates multiple stages in the development and survival of B-1 cells. Mol Immunol 44(10):2719-28 |
| abstractText | B-1 cells are important players in the first line of defense against pathogens. According to current models for the origin of B-1 cells, they either represent a separate lineage from conventional B-2 cells or differentiate from conventional B-2 cells via an intermediate, B-1(int), in response to positive selection by antigen. Here we show that Btk, a Tec family kinase that mediates B cell antigen receptor (BCR) signaling, is required at multiple stages of B-1 cell development. VH12 anti-phosphatidylcholine (PtC) IgH transgenic mice provide a model for the induced differentiation of B-1 cells. This transgene selects for PtC-reactive cells and induces them to adopt a B-1 phenotype. Both processes have been shown to depend on Btk. To determine whether this is secondary to a requirement for Btk in the development of mature B-2 cells, we crossed VH12 transgenic mice to mice expressing low levels of Btk. B-2 cell development occurs normally in Btk(lo) mice despite reduced responsiveness to BCR crosslinking. Analysis of VH12.Btk(lo) mice reveals that Btk regulates the B-1(int) to B-1 transition and/or the survival of splenic B-1 cells, in part via a mechanism independent of its role in BCR signaling. We also show that Btk mediates the survival of, and expression of IL-10 by, those B-1 cells that do develop and migrate to the peritoneum. Multiple roles for Btk in B-1 cell development and maintenance may explain the particular sensitivity of this population to mutations in components of Btk signaling pathways. |
