Precursor B lymphocytes--specific monoclonal antibodies and genes.

Abstract

The pool of mature, surface immunoglobulin (Ig) positive, antigen-sensitive B cells of a mouse has been estimated to contain 5 × 108 to 109 cells (Osmond 1986). Development from pluripotent stem cells and committed progenitors generates daily some 5 × 107 cells, of which 3 × 106 enter the pool of mature B cells. The same number of mature B cells must consequently die daily to keep the pool at a constant size. The immediate precursors of the mature B cells, called pre B cells, can be identified to be at various stages of their development by the genomic context in which their Ig gene loci are found. Thus, rearrangement of a DH to a JH segment on the Ig heavy (H) chain locus precedes that of V..