The Protean Nature of Cells in the B Lymphocyte Lineage

The Division of Basic Sciences, Fox Chase Cancer Center, Philadelphia, PA 19111, USA.
Immunity (Impact Factor: 21.56). 07/2007; 26(6):703-14. DOI: 10.1016/j.immuni.2007.05.013
Source: PubMed


The subdivision of bone marrow (BM) with surface markers and reporter systems and the use of multiple culture and transplantation assays to assess differentiation potential have led to extraordinary progress in defining stages of B lymphopoiesis between the hematopoietic stem cell and B cell receptor (BCR)-expressing lymphocytes. Despite the lack of standard nomenclature and a series of technical issues that still need to be resolved, there seems to be a general consensus regarding the major route to becoming a B cell. Nevertheless, evidence that additional, minor pathways through which B lineage cells are generated exists, and a new appreciation that lymphoid progenitors are protean and able to alter their differentiation potential during embryogenesis and after birth in response to infections suggests that a full understanding of B cell development and how it is regulated has not yet been attained.

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    • "B cells at various stages of development may also be phenotyped based on the expression of specific surface markers [69], [70]. dCK KO mice have a partial block at the pro-B (CD43+CD19+) to pre-B cell (CD43−CD19+) transition [36]. "
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    PLoS ONE 08/2014; 9(8):e104125. DOI:10.1371/journal.pone.0104125 · 3.23 Impact Factor
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    • "Hardy fraction B+C cells had a lower frequency of cell death in the absence of MyD88 in DCs (Figure 3G). Because survival and growth of fraction B+C cells is mediated by IL-7 (Hardy et al., 2007), those findings suggested stronger IL-7R signaling in DC-Myd88 D mice. Importantly, IL-7R signaling is inhibited by IFN-I. "
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    Immunity 03/2013; 38(3). DOI:10.1016/j.immuni.2012.11.017 · 21.56 Impact Factor
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    • "A number of miR-155 targets with important roles in B-cell differentiation, including Bach1, fos, c-myb, Pu.1 and C/EBPβ have been identified in the past [21], [24], [27], [28], [39], [42], [58], [66]. We have confirmed downregulation of two of the above genes (c-myb and fos) as well as of Jarid2 in kshv-miR-K12-11and hsa-miR-155 expressing BM cells, an observation which supports the idea that miR-155 may contribute to the silencing of these targets during B-cell development (it should be pointed out, however, that the marked repression very likely also involves other mechanisms that may directly act on the transcriptional level). "
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    PLoS ONE 11/2012; 7(11):e49435. DOI:10.1371/journal.pone.0049435 · 3.23 Impact Factor
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