| First Author | Choi MS | Year | 1996 |
| Journal | Eur J Immunol | Volume | 26 |
| Issue | 3 | Pages | 676-82 |
| PubMed ID | 8605937 | Mgi Jnum | J:31993 |
| Mgi Id | MGI:79495 | Doi | 10.1002/eji.1830260325 |
| Citation | Choi MSK, et al. (1996) Expression of bcl-x during mouse B cell differentiation and following activation by various stimuli. Eur J Immunol 26(3):676-682 |
| abstractText | We have studied the expression of the novel anti-apoptotic protein bcl-x during mouse B cell differentiation and activation. We find that bcl-x is expressed throughout all stages of B cell differentiation in the bone marrow and is only down-regulated in mature (sIgD(+)) B cells. Immature peripheral B cells express low levels of bcl-x even in adult animals, whereas mature resting B cells do not. Mature B cells re-express the protein following activation, achieving maximal levels after 36-48 h. The highest levels of bcl-x are observed with potent comitogenic stimuli (such as anti-CD40 + anti-Ig): B cells first express bcl-x in the G1 phase of the cell cycle and contain maximal levels in S phase. In addition, B cells from CBA/N mice, which do not proliferate when stimulated with anti-Ig, anti-CD40, or both, exhibited only low levels of the protein following culture with these stimuli. To investigate the functional significance of bcl- x in activated B cells. we tested their sensitivity to apoptosis induced by the Ca2+ ATPase inhibitor thapsigargin: B cell blasts activated with anti-CD40 and anti-Ig were resistant to this agent. The available data therefore suggest that bcl-x fulfils two roles in B cells: it promotes survival of immature B cells (which lack bcl- 2) and secondly, it apparently plays an additional role in protecting activated mature B cells (perhaps those in germinal centers) from apoptotic stimuli. |
