title: A transgenic marker for mouse B lymphoid precursors.
abstract: Three lines of transgenic mice have been generated which express human CD25 under the control of the 722-base pair region located immediately 5' of the precursor (pre)-B cell-specific lambda5 gene. All three strains express human CD25 in parallel to endogenous lambda5 on pre-B cells, but not on mature B lymphocytes or other blood cell lineages. High expression of human CD25 on B lineage cells of transgenic mice has allowed the identification of a new B220+CD19-lambda5+ precursor of the B220+CD19+lambda5+ c-kit+ pre-BI cells. Both types of precursors are clonable on stromal cells in the presence of interleukin-7. The CD19- precursors have a sizeable part of their immunoglobulin heavy chain gene loci in germline configuration, while the CD19+ pre-BI cells are predominantly DJH rearranged. The results indicate that random integration of the 722-bp 5' region of the lambda5 gene into the mouse genome confers tissue and differentiation stage-specific expression of a transgene.
authors.affiliation: Department of Cellular and Molecular Biology, Immunology Group, Lund, Sweden.
authors.forename: I L
authors.initials: IL
authors.lastname: Mårtensson
authors.forename: F
authors.initials: F
authors.lastname: Melchers
authors.forename: T H
authors.initials: TH
authors.lastname: Winkler
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000166:cytology / Q000276:immunology*; D001853:Bone Marrow / Q000276:immunology; D001854:Bone Marrow Cells; D019070:Cell Lineage; D002478:Cells, Cultured; D005434:Flow Cytometry; D006801:Humans; D051379:Mice; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D008822:Mice, Transgenic; D015375:Receptors, Interleukin-2 / Q000276:immunology
chemical_list: D015375:Receptors, Interleukin-2