title: IL-4 regulates differentiation and proliferation of human precursor B cells.
abstract: The mechanism by which precursor and pre-B cells undergo differentiation is unclear; however, it is known that growth factors play an important role in this maturation process. The lymphokine, IL-4 has been shown to increase expression of class II Ag on B cells and induce B cell proliferation. In the murine system, IL-4 induced differentiation of precursor B cells into pre-B cells. In order to analyze growth factors on B cell development we have established an in vitro culture system for human bone marrow cells. We found that in the presence of IL-4, normal human precursor and pre-B cells can be induced to differentiate in the absence of cell proliferation with four days of culture. Furthermore, IL-4 depressed proliferation induced by supernatant from a T cell line. The differentiation was measured by an increase in both the number of cytoplasmic mu and surface IgM-positive cells. The effect of IL-4 on precursor and pre-B cell differentiation was detected as soon as 14 h of exposure to the lymphokine in the absence of an adherent feeder layer. These data suggest that IL-4 directly affects the differentiation process of normal human precursor and pre-B cells, and may antagonistically affect cell proliferation.
authors.affiliation: Department of Pathology, University of Southern California School of Medicine, Los Angeles 90033.
authors.forename: F M
authors.initials: FM
authors.lastname: Hofman
authors.forename: M
authors.initials: M
authors.lastname: Brock
authors.forename: C R
authors.initials: CR
authors.lastname: Taylor
authors.forename: B
authors.initials: B
authors.lastname: Lyons
mesh_terms: D000944:Antigens, Differentiation, B-Lymphocyte / Q000032:analysis; D001402:B-Lymphocytes / Q000166:cytology* / Q000276:immunology; D001854:Bone Marrow Cells; D002454:Cell Differentiation / Q000187:drug effects*; D002478:Cells, Cultured; D006801:Humans; D007377:Interleukin-3 / Q000494:pharmacology; D015847:Interleukin-4; D007378:Interleukins / Q000494:pharmacology*; D008213:Lymphocyte Activation / Q000187:drug effects*; D011994:Recombinant Proteins / Q000494:pharmacology; D013234:Stem Cells / Q000166:cytology* / Q000276:immunology
chemical_list: D000944:Antigens, Differentiation, B-Lymphocyte; D007377:Interleukin-3; D007378:Interleukins; D011994:Recombinant Proteins; D015847:Interleukin-4