title: Characterization of mercuric mercury (Hg2+)-induced lymphoblasts from patients with mercury allergy and from healthy subjects.
abstract: Hg2+ induces lymphocyte proliferation when added to cell cultures from both healthy and mercury-allergic subjects. Consequently, when measuring DNA synthesis a possible Hg2+-specific response, resulting from proliferating memory cells, cannot be discriminated from a non-allergic response. The mechanism behind this non-allergic response is unknown but a superantigenic effect of Hg2+ has been suggested. In this study, five mercury-allergic patients, with oral lichen planus (OLP) lesions adjacent to dental amalgam and a positive patch test to Hg0, and five healthy subjects without amalgam were examined. The immunophenotype and the T cell receptor Vbeta (TCR Vbeta) repertoire of Hg2+-induced lymphoblasts as well as the expression of the lymphocyte activation markers CD23 and CD134 were analysed for possible differences between healthy and allergic subjects. The mechanism of Hg2+-induced proliferation was examined by comparing the TCR Vbeta expression of Hg- and staphylococcal enterotoxin B (SEB)-activated lymphoblasts, the latter used as a positive superantigen control. It was not possible to discriminate between mercury-allergic and healthy subjects using the immunophenotype or the TCR Vbeta profile of the Hg2+-induced lymphoblasts or the expression of CD23 and CD134. However, Hg2+-induced CD4+ lymphoblasts showed a skewing towards Vbeta2. This relative increase in Vbeta2 was only detected in the CD4+ but not in the CD8+ lymphoblast population. In conclusion, Hg2+ induced a proliferation-dependent skewing towards CD4+ but not CD8+ lymphocytes expressing Vbeta2. In this respect Hg2+ differs from the classical bacterial superantigen SEB, which also stimulates unique TCR Vbeta families among CD8+ cells.
authors.affiliation: Department of Health and Environment, Division of Molecular and Immunological Pathology, Linköping University, Linköping, Sweden. Karin.Cederbrant@astrazeneca.com
authors.forename: K
authors.initials: K
authors.lastname: Cederbrant
authors.forename: P
authors.initials: P
authors.lastname: Hultman
mesh_terms: D000328:Adult; D015703:Antigens, CD / Q000096:biosynthesis / Q000145:classification / Q000276:immunology; D001402:B-Lymphocytes / Q000187:drug effects / Q000276:immunology*; D015415:Biomarkers; D015496:CD4-Positive T-Lymphocytes / Q000145:classification / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000145:classification / Q000276:immunology; D002478:Cells, Cultured; D004247:DNA / Q000096:biosynthesis; D005260:Female; D006801:Humans; D006967:Hypersensitivity / Q000097:blood / Q000276:immunology*; D016130:Immunophenotyping; D007963:Leukocytes, Mononuclear / Q000166:cytology / Q000187:drug effects; D008213:Lymphocyte Activation / Q000276:immunology; D008297:Male; D008627:Mercuric Chloride / Q000276:immunology* / Q000494:pharmacology; D008875:Middle Aged; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000096:biosynthesis; D013601:T-Lymphocytes / Q000187:drug effects / Q000276:immunology*
chemical_list: D015703:Antigens, CD; D015415:Biomarkers; D016693:Receptors, Antigen, T-Cell, alpha-beta; D008627:Mercuric Chloride; D004247:DNA