Signaling through the preBCR

Data obtained using genetically manipulated mice have indicated a requirement for pre-BCR membrane expression and signaling for continued survival and development of pre-B cells. Loss of BCR expression or function results in abortive maturation and cell death at all stages where it has been assessed. In fact, once initiated, disruption in assembly, expression, or signaling capability results in developmental arrest and cell death (Gauld et al., 2002 Kraus et al., 2004 Lam et al., 1997 Meffre...

The hematopoietic microenvironment

The above discussion has documented the cell-intrinsic patterns of gene expression necessary for the development of B lymphocytes in the bone marrow. To what degree patterns of gene expression are affected by signals from the hematopoietic microenvironment remains an issue. In order to set the stage for a discussion of this issue, the anatomical organization of the bone marrow and the mechanisms by which signals from it may impact B lymphocyte development are briefly presented. Hematopoiesis...