title: High rate of mutation reporter gene inactivation during human T cell proliferation.
abstract: Caspase activation and degradation of deoxyribonucleic acid (DNA) damage response factors occur during in vitro T-cell proliferation, and an increased frequency of hypoxanthine-guanine phosphoribosyltransferase (HPRT)-negative variants have been reported in conditions associated with in vivo T-cell proliferation. We have applied two human somatic cell mutation reporter assays, for the HPRT and phosphatidylinositol glycan class A (PIG-A) genes, to human T cells activated in vitro with anti-CD3 and anti-CD28. We demonstrate proliferation throughout 6 weeks of cultivation, and find that the frequency of variant cells phenotypically negative for HPRT and PIG-A, respectively, increases from 10(-5) up to 10(-3) -10(-2). We also report preliminary evidence for low-density CpG methylation in the HPRT promoter suggesting that epigenetic modification may contribute to this markedly heightened rate of gene inactivation.
authors.affiliation: Department of Laboratory Medicine, Section of Medical Microbiology, Lund University, Malmo University Hospital, S-205 02, Malmo, Sweden.
authors.forename: Aida
authors.initials: A
authors.lastname: Gabdoulkhakova
authors.forename: Gunnel
authors.initials: G
authors.lastname: Henriksson
authors.forename: Nadezhda
authors.initials: N
authors.lastname: Avkhacheva
authors.forename: Alexander
authors.initials: A
authors.lastname: Sofin
authors.forename: Anders
authors.initials: A
authors.lastname: Bredberg
mesh_terms: D001483:Base Sequence; D053148:Caspase 3 / Q000378:metabolism; D049109:Cell Proliferation; D018899:CpG Islands; D004249:DNA Damage; D017931:DNA Primers / Q000235:genetics; D017930:Genes, Reporter; D006801:Humans; D007041:Hypoxanthine Phosphoribosyltransferase / Q000235:genetics; D007125:Immunogenetics; D066298:In Vitro Techniques; D008213:Lymphocyte Activation / Q000235:genetics; D008565:Membrane Proteins / Q000235:genetics; D009154:Mutation; D013601:T-Lymphocytes / Q000166:cytology* / Q000276:immunology* / Q000378:metabolism
chemical_list: D017931:DNA Primers; D008565:Membrane Proteins; C080086:phosphatidylinositol glycan-class A protein; D007041:Hypoxanthine Phosphoribosyltransferase; D053148:Caspase 3