| First Author | Allende ML | Year | 2010 |
| Journal | J Exp Med | Volume | 207 |
| Issue | 5 | Pages | 1113-24 |
| PubMed ID | 20404103 | Mgi Jnum | J:161236 |
| Mgi Id | MGI:4457826 | Doi | 10.1084/jem.20092210 |
| Citation | Allende ML, et al. (2010) S1P1 receptor directs the release of immature B cells from bone marrow into blood. J Exp Med 207(5):1113-24 |
| abstractText | S1P1 receptor expression is required for the egress of newly formed T cells from the thymus and exit of mature T and B cells from secondary lymphoid organs. In this study, we deleted the expression of the S1P1 receptor gene (S1pr1) in developing B cells in the bone marrow. Although B cell maturation within the bone marrow was largely normal in the B cell-specific S1pr1 knockout (B-S1pr1KO) mice, their newly generated immature B cells appeared in the blood at abnormally low numbers as compared with control mice. In the bone marrow of B-S1pr1KO mice, immature B cells in contact with the vascular compartment displayed increased apoptosis as compared with control mice. Forced expression of CD69, a negative regulator of S1P1 receptor expression, in developing bone marrow B cells also reduced the number of immature B cells in the blood. Attenuation of CXCR4 signaling, which is required for the proper retention of developing B cells in bone marrow, did not release immature B cells into the blood of B-S1pr1KO mice as effectively as in control mice. Our results indicate that the S1P1 receptor provides a signal necessary for the efficient transfer of newly generated immature B cells from the bone marrow to the blood. |
