title: In vivo identification of lymphocyte subsets exhibiting transcriptionally active NF-kappaB/Rel complexes.
abstract: To analyze the NF-kappaB/Rel activity pattern in a living organism, we previously generated transgenic mice carrying a kappaB-dependent lacZ gene. In situ analysis of both primary and secondary lymphoid organs revealed a strong NF-kappaB transcriptional activity in antigen-presenting cells, some endothelial cells and sinus lining cells of the lymph node capsula with very little activity in lymphocytes and thymocytes. Using fluorescein-di-beta-D-galactopyranoside (FDG) as a vital substrate for the beta-galactosidase, we re-examined by flow cytometry the NF-kappaB/Rel transcriptional activity in our mouse model. We report here that such constitutive NF-kappaB/Rel activity was significantly detected in thymocytes at the CD44+CD25(-) stage. This constitutive activity extended with CD25 expression to the majority of the CD44(-)CD25(+) thymocytes and was then restricted to a few mature T cells. In the spleen, constitutive NF-kappaB/Rel activity was found in most B cells, unlike T cells which were largely negative. Virgin IgD(+) B cells expressed higher levels of NF-kappaB transcriptional activity than other B cell types. Altogether, these results suggest that NF-kappaB/Rel complexes are key players in the in vivo differentiation of IgD(+) B lymphocytes and possibly CD25(+) thymocytes.
authors.affiliation: Unité de Biologie Moléculaire de l'Expression Génique, URA 1773 CNRS, Institut Pasteur, 28 rue du Dr Roux, 75724 Paris Cedex 15, France.
authors.forename: J
authors.initials: J
authors.lastname: Feuillard
authors.forename: S
authors.initials: S
authors.lastname: Mémet
authors.forename: B
authors.initials: B
authors.lastname: Goudeau
authors.forename: A
authors.initials: A
authors.lastname: Lilienbaum
authors.forename: R
authors.initials: R
authors.lastname: Schmidt-Ullrich
authors.forename: M
authors.initials: M
authors.lastname: Raphaël
authors.forename: A
authors.initials: A
authors.lastname: Israël
mesh_terms: D000818:Animals; D005434:Flow Cytometry; D005456:Fluorescent Dyes; D018960:Hyaluronan Receptors / Q000032:analysis; D007072:Immunoglobulin D / Q000276:immunology; D007145:Immunoglobulin kappa-Chains / Q000235:genetics; D007763:Lac Operon; D016131:Lymphocyte Subsets / Q000201:enzymology / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D016328:NF-kappa B / Q000032:analysis / Q000235:genetics / Q000276:immunology*; D015375:Receptors, Interleukin-2 / Q000032:analysis; D013154:Spleen / Q000276:immunology; D013950:Thymus Gland / Q000276:immunology; D014158:Transcription, Genetic; D001616:beta-Galactosidase / Q000032:analysis
chemical_list: D005456:Fluorescent Dyes; D018960:Hyaluronan Receptors; D007072:Immunoglobulin D; D007145:Immunoglobulin kappa-Chains; D016328:NF-kappa B; D015375:Receptors, Interleukin-2; D001616:beta-Galactosidase