Regulation of growth and differentiation of human B cells

Abstract

Activation process of B lymphocytes into immunoglobulin (Ig)-secreting cells can be dissected into three steps, i.e., activation, proliferation and differentiation (1–3). It has been demonstrated by several investigators that B cell specific growth and differentiation factors are involved in the process of proliferation and differentiation of activated B cells (4–10). The presence of two different kinds of B cell growth factors, BCGF-I or BSF-pI and BCGF-II, was reported in human (11) as well as in murine systems (12). BCGF-I induces proliferation of anti-IgM-stimulated human or murine B cells as well as SAC (Staphylococcus aureus Cowan I)-stimulated human B cells. Activated but not resting B cells are able to adsorb the activity of BCGF-I, suggesting the induction of the expression of receptors for BCGF-I on activated B cells. However, a recent study showed an increased expression of Ia antigen on resting B cells by stimulation with BCGF-I, suggesting the presence of BCGF-I receptors even on resting B cells, although BCGF-I induces proliferation only in activated B cells (13).KeywordsImmunological PropertyIntracellular MediatorMaximum ProliferationCell Stimulatory FactorVaring ConcentrationThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.