Fetal liver organ cultures allow the proliferative expansion of pre-B receptor-expressing pre-B-II cells and the differentiation of immature and mature B cells in vitro.
We describe the phenotypic and functional properties of B lineage cells developing in fetal liver organ cultures (FLOC) of mouse embryos at day 14 or 15 of gestation which contain pro/pre-B-I cells. FLOC B cell development proceeds to mature IgM+, IgD+ and CD23+ lipopolysaccharide-reactive B cells within a culture period of 5-6 days. The phenotypes and relative proportions of pro/pre-B-I, pre-B-II, immature and mature B cells from FLOC were similar to that seen in livers freshly isolated from age-matched, i.e. newborn, mice. More importantly, the numbers of cells recovered in the different B lineage subpopulations from FLOC were close to those developed in vivo. Hence, in contrast to single-cell suspension cultures of fetal liver, FLOC allow the proliferative expansion of pre-B cell receptor-expressing pre-B-II cells. FLOC from embryos of mice with targeted mutations in the RAG-2 and lambda5 genes, which cannot expand by proliferative expansion of their pre-B-II compartment in vivo because they cannot express a pre-B cell receptor on their surface, show this same defect in vitro. FLOC are accessible to the action of mAb and cytokines. Thus, addition of anti-IL-7 receptor mAb to FLOC of normal mice inhibits B cell development at the transition of pro/pre-B-I to pre-B-II cells. This inhibition is reversed by addition of excess rIL-7. Addition of IL-7 alone stimulates the proliferation of pro/pre-B-I cells and inhibits their differentiation to pre-B-II and immature B cells, as it does in single-cell suspension cultures. FLOC should be useful to study the effects of other mAb, cytokines, ligands and other molecules on early B cell development.
Ceredig
R
R
Basel Institute for Immunology, Switzerland.
ten Boekel
E
E
Rolink
A
A
Melchers
F
F
Andersson
J
J
D000818:Animals; D000911:Antibodies, Monoclonal / Q000494:pharmacology; D000918:Antibody Specificity; D001402:B-Lymphocytes / Q000166:cytology / Q000502:physiology* / Q000648:ultrastructure; D002454:Cell Differentiation / Q000502:physiology; D004622:Embryo, Mammalian; D015851:Interleukin-7 / Q000378:metabolism / Q000494:pharmacology; D008099:Liver / Q000166:cytology* / Q000502:physiology; D008213:Lymphocyte Activation / Q000502:physiology; D051379:Mice; D008810:Mice, Inbred C57BL; D009924:Organ Culture Techniques; D011947:Receptors, Antigen, B-Cell / Q000096:biosynthesis*; D018123:Receptors, Interleukin / Q000276:immunology
D000911:Antibodies, Monoclonal; D015851:Interleukin-7; D011947:Receptors, Antigen, B-Cell; D018123:Receptors, Interleukin