title: Characterization of the CDR3 region of rearranged alpha heavy chain genes in human fetal liver.
abstract: The human fetal liver is an early site for B cell development. Pre B cells are first detectable in human fetal life at 8 weeks of gestation, when the rearrangement of the mu heavy chain genes starts. In this study we characterize the CDR3 region of rearranged alpha heavy chain transcripts from four human fetal livers ranging from 8 to 11 weeks of gestation. Each fetal liver showed a limited number of variations in CDR3 sequences compared with adult peripheral blood mononuclear cells (PBMC). Sequence analysis of 91 clones demonstrated that there was no preference for the usage of a certain JH gene segment, whereas a preference for usage of DH family genes, DXP and DLR, was seen in most cases during early fetal life. This is the first study where rearranged alpha heavy chain genes in fetal liver have been characterized. Our data suggest that the usage of JH genes is random, while there is a preference for DH family genes in human fetal liver.
authors.affiliation: Department of Biosciences, NOVUM, Karolinska Institute, Huddinge, Sweden.
authors.forename: B
authors.initials: B
authors.lastname: Baskin
authors.forename: K B
authors.initials: KB
authors.lastname: Islam
authors.forename: C I
authors.initials: CI
authors.lastname: Smith
mesh_terms: D000328:Adult; D015703:Antigens, CD / Q000235:genetics / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology*; D001483:Base Sequence; D051925:CD79 Antigens; D022801:Complementarity Determining Regions; D018507:Gene Expression Regulation, Developmental; D015326:Gene Rearrangement, B-Lymphocyte, Heavy Chain; D005803:Genes, Immunoglobulin; D006801:Humans; D007143:Immunoglobulin Heavy Chains / Q000235:genetics* / Q000276:immunology; D007137:Immunoglobulin alpha-Chains / Q000235:genetics* / Q000276:immunology; D008099:Liver / Q000196:embryology / Q000276:immunology*; D008969:Molecular Sequence Data; D011947:Receptors, Antigen, B-Cell / Q000235:genetics / Q000276:immunology
chemical_list: D015703:Antigens, CD; D051925:CD79 Antigens; C497881:CD79A protein, human; D022801:Complementarity Determining Regions; D007143:Immunoglobulin Heavy Chains; D007137:Immunoglobulin alpha-Chains; D011947:Receptors, Antigen, B-Cell