First Author | Merino R | Year | 1994 |
Journal | EMBO J | Volume | 13 |
Issue | 3 | Pages | 683-91 |
PubMed ID | 8313913 | Mgi Jnum | J:16871 |
Mgi Id | MGI:64930 | Doi | 10.1002/j.1460-2075.1994.tb06307.x |
Citation | Merino R, et al. (1994) Developmental regulation of the Bcl-2 protein and susceptibility to cell death in B lymphocytes. EMBO J 13(3):683-91 |
abstractText | Cell death is a prominent feature of B cell development. For example, a large population of B cells dies at the pre-B cell stage presumably due to the failure to express a functional immunoglobulin receptor. In addition, developing B cells expressing antigen receptors for self are selectively eliminated at the immature B cell stage. The molecular signals that control B cell survival are largely unknown. The product of the bcl-2 proto-oncogene may be involved as its overexpression inhibits apoptotic cell death in a variety of biological systems. However, the physiological role of the endogenous Bcl-2 protein during B cell development is undetermined. Here we show a striking developmental regulation of the Bcl-2 protein in B lymphocytes. Bcl-2 is highly expressed in CD43+ B cell precursors (pro-B cells) and mature B cells but downregulated at the pre-B and immature B cell stages of development. We found that Bcl-2 expressed by B cells is a long-lived protein with a half-life of approximately 10 h. Importantly, susceptibility to apoptosis mediated by the glucocorticoid hormone dexamethasone is stage-dependent in developing B cells and correlates with the levels of Bcl-2 protein. Furthermore, expression of a bcl-2 transgene rescued pre-B and immature B cells from dexamethasone-induced cell death, indicating that Bcl-2 can inhibit the apoptotic cell death of progenitors and early B cells. Taken together, these findings argue that Bcl-2 is a physiological signal controlling cell death during B cell development. |