| First Author | Lam QL | Year | 2007 |
| Journal | Int Immunol | Volume | 19 |
| Issue | 3 | Pages | 267-76 |
| PubMed ID | 17229817 | Mgi Jnum | J:118698 |
| Mgi Id | MGI:3700118 | Doi | 10.1093/intimm/dxl143 |
| Citation | Lam QL, et al. (2007) Impaired V(D)J recombination and increased apoptosis among B cell precursors in the bone marrow of c-Abl-deficient mice. Int Immunol 19(3):267-76 |
| abstractText | Previous studies on c-Abl-deficient mice have shown high post-natal mortality and lymphopenia. However, the mechanisms by which c-Abl may influence B lymphopoiesis remain obscure. In this study, we analyzed B cell sub-populations at various differentiation stages in the bone marrow (BM) of c-Abl-deficient mice. Phenotypic analyses revealed that c-Abl(-/-) pro-B cells were reduced to half of normal incidence and absolute number, while pre-B cells showed an even greater reduction. Both c-Abl(-/-) pro-B and pre-B cell populations showed considerably elevated apoptosis ex vivo and in short-term culture but their cell cycle progression was not impaired. In contrast, apoptosis of immature IgM(+)IgD(-) B lymphocytes remained at normal control levels. Inhibition of c-Abl activity by STI571 in normal BM cultures significantly increased apoptosis in B cell precursors while the survival of immature B cells was not affected. To determine whether c-Abl deficiency affects Ig heavy-chain rearrangement, we found that the frequency of V(D)J recombination was markedly reduced by 15-fold in c-Abl(-/-) pro-B cells compared with the control values. However, no perturbation in the levels of signal-end recombination intermediates was found. Taken together, we propose that c-Abl mediates a stage-specific anti-apoptotic response in precursor B cells and is required for efficient V(D)J recombination during B cell development. |
