title: Effects of cadmium and vanadium ions on antigen-induced signaling in CD4(+) T cells.
abstract: Heavy metal environmental pollutants modulate antigen-directed responses by T lymphocytes, but the molecular mechanisms by which certain metal ions exert their effects are only poorly understood. We tested the hypothesis that cadmium and vanadium ions alter antigen-induced T cell signal transduction pathways in CD4(+) T helper cells. We used CD4(+) primary T lymphocytes and splenic T cells from DO.11.10 T cell receptor transgenic mice. We determined the effects of cadmium chloride and sodium orthovanadate at concentrations that did not induce apoptotic cell death, but affected cytokine or proliferation responses to antigenic stimulation. We used electrophoretic mobility shift assays to measure effects of cadmium and vanadium ions on antigen-induced activation of the nuclear transcriptional regulator proteins, nuclear factor-kappaB, cyclic AMP response element binding protein, nuclear factor of activated T cells, and activator protein-1. Different signaling pathways lead to activation of these transcription factors. Our results suggest that the two heavy metal ions differentially affect signaling pathways. This knowledge will help in the development of molecular epidemiological assays.
authors.affiliation: Department of Microbiology and Immunology, The University of Texas Medical Branch, 301 University Boulevard, Galveston, TX 77555-1070, USA.
authors.forename: K
authors.initials: K
authors.lastname: Lee
authors.forename: X
authors.initials: X
authors.lastname: Shen
authors.forename: R
authors.initials: R
authors.lastname: König
mesh_terms: D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology; D000941:Antigens / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects* / Q000276:immunology*; D002104:Cadmium / Q000276:immunology* / Q000633:toxicity; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D007091:Image Processing, Computer-Assisted; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008822:Mice, Transgenic; D015398:Signal Transduction / Q000187:drug effects / Q000276:immunology; D013154:Spleen / Q000187:drug effects / Q000276:immunology; D014157:Transcription Factors / Q000032:analysis / Q000096:biosynthesis; D014639:Vanadium / Q000276:immunology* / Q000633:toxicity
chemical_list: D000941:Antigens; D014157:Transcription Factors; D002104:Cadmium; D014639:Vanadium