title: In interleukin-7-transgenic mice, increasing B lymphopoiesis increases follicular but not marginal zone B cell numbers.
abstract: Follicular and marginal zone B cells constitute the vast majority of mature B cells in the adult spleen. The inter-relationships between these two functionally and phenotypically distinct subpopulations of B cells remain unclear. In situations of decreased bone marrow B lymphopoiesis, the proportion of spleen marginal zone B cells increases, but the consequence of increasing B lymphopoiesis on marginal zone B cells has not been investigated. Using interleukin-7-transgenic mice, in which B lymphopoiesis is significantly increased, we show that the number of follicular B cells increased about fivefold but the number of marginal zone B cells decreased. Functional and phenotypic analysis, including in vivo bromodeoxyuridine labeling experiments, showed that marginal zone B cells in transgenic mice were indistinguishable from controls. Mixed radiation bone marrow chimeras showed that marginal zone B cells developed equally well from both normal and transgenic adult bone marrow B cell progenitors. Taken together, these results suggest that interleukin-7 does not influence the lineage choice between follicular and marginal zone B cells and that the number of cells in each compartment is independently regulated.
authors.affiliation: Unité 548 INSERM, DRDC, Commissariat à l'Energie Atomique-Grenoble, Grenoble, France. ceredig@dsvsud.cea.fr
authors.forename: Rhodri
authors.initials: R
authors.lastname: Ceredig
authors.forename: Nabil
authors.initials: N
authors.lastname: Bosco
authors.forename: Patrice N
authors.initials: PN
authors.lastname: Maye
authors.forename: Jan
authors.initials: J
authors.lastname: Andersson
authors.forename: Antonius
authors.initials: A
authors.lastname: Rolink
mesh_terms: D000818:Animals; D018941:Antigens, CD19 / Q000378:metabolism; D001402:B-Lymphocytes / Q000378:metabolism*; D015851:Interleukin-7 / Q000235:genetics*; D038041:Lymphopoiesis / Q000502:physiology*; D051379:Mice; D008822:Mice, Transgenic; D013154:Spleen / Q000378:metabolism*
chemical_list: D018941:Antigens, CD19; D015851:Interleukin-7