B-CELL DEVELOPMENT AND DIFFERENTIATION

The initial phases of B cell development depend on interactions betwee n the cell surface molecules and secreted products of stromal cells wi th their receptor-ligand partners on lymphoid progenitors. Recent rese arch in this area has greatly advanced our understanding of B cell dev elopment and differentiation. Antigen receptors on pre-B and B cells p lay key roles in the progression of this differentiation process, as r evealed by targeted and inherited gene mutations that disrupt B cell d evelopment and by the transgenic repair of these mutations in mice.