Effect of growth and differentiation stimuli on the development of antigen-responsive B cells in fetal liver.
The development of the B cell immune repertoire was studied using an in vitro fetal organ culture system. In order to analyze the mechanism by which B cell precursors clonally expand and diversify, fetal lymphoid tissues were incubated in the presence of several factors known to influence B cell differentiation: IL-1, IL-2, WEHI-3 culture supernatant containing IL-3, and a factor from a cyclic neutropenia patient (CNF). By analyzing the effect of exogenous factors on the frequency of antigen-responsive B cells, the ability of the factor to either inhibit or enhance clonal expansion was determined. It was found that the addition of IL-1, WEHI-3 supernatant, or CNF increased the frequency of DNP-responsive B cells suggesting an enhancement of clonal expansion. IL-2, on the other hand, did not alter the frequency of antigen-responsive B cells. The effect of added factors on the kinetics of appearance of phosphorylcholine (PC)-responsive B cells, which are known to be acquired in ontogeny about 2 weeks later than DNP-responsive B cells, was also analyzed. The data indicate that CNF, unlike IL-1, IL-2, and WEHI-3 culture supernatant, results in an earlier appearance of PC-responsive B cells. These results suggest that soluble factors may play a role in the generation of the B cell repertoire.
Teale
J M
JM
Department of Microbiology, University of Texas Health Science Center, San Antonio 78284.
Landreth
K S
KS
D000818:Animals; D001402:B-Lymphocytes / Q000166:cytology* / Q000187:drug effects / Q000637:transplantation; D002454:Cell Differentiation / Q000187:drug effects; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005333:Fetus / Q000276:immunology; D006133:Growth Substances / Q000494:pharmacology*; D006241:Haptens / Q000276:immunology; D007130:Immunoglobulin Idiotypes / Q000032:analysis; D007150:Immunohistochemistry; D008099:Liver / Q000196:embryology / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D009924:Organ Culture Techniques; D013234:Stem Cells / Q000187:drug effects
D006133:Growth Substances; D006241:Haptens; D007130:Immunoglobulin Idiotypes