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- Cederbrant, Karin, et al.
(författare)
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In vitro Lymphocyte Proliferation as Compared to Patch Test Using Gold, Palladium and Nickel
- 1997
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Ingår i: International Archives of Allergy and Immunology. - : S. Karger AG. - 1018-2438 .- 1423-0097. ; 112:3, s. 212-217
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Tidskriftsartikel (refereegranskat)abstract
- Background: A conventional lymphocyte transformation test (LTT) was compared to the commercially available MELISA® (memory lymphocyte immuno-stimulation assay), a lymphoproliferative assay that has been suggested to be a valuable instrument for the diagnosis of metal allergy. Sensitivity and specificity of the two assays were calculated using a patch test as a reference method.Methods: 34 patients were patch-tested for gold sodium thiosulfate, palladium chloride and nickel sulfate, and the lymphocyte proliferation to these metals was tested in vitro using mononuclear cells from peripheral blood.Results: No significant differences regarding sensitivity and specificity were found between MELISA and conventional LTT. The sensitivity varied between 55 and 95% and the specificity between 17 and 79%.Conclusions: The low specificity of the two in vitro assays suggests that they are not useful for diagnosis of contact allergy to the metals gold, palladium and nickel, since a large number of false-positive results will be obtained.
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| 2. |
- Cederbrant, Karin, et al.
(författare)
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In vitro Lymphoproliferative Assays with HgCl2 Cannot Identify Patients with Systemic Symptoms Attributed to Dental Amalgam
- 1999
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Ingår i: Journal of Dental Research. - : SAGE Publications. - 0022-0345 .- 1544-0591. ; 78:8, s. 1450-1458
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Tidskriftsartikel (refereegranskat)abstract
- Dental amalgam is suspected, by some exposed individuals, to cause various systemic psychological, sensory, and neurological symptoms. Since not all amalgam-bearers experience such reactions, an individual characteristic—for example, a susceptible immune system—might explain these conditions. In vitro lymphocyte proliferation is a valuable tool in the diagnosis of allergy. With HgCl2 as the antigen, however, the test is hampered, because Hg2+ can cause unspecific lymphocyte proliferation, optimal at 1.4 to 9.5 μg HgCl2/mL. Recently, the use of suboptimal HgCl2 concentrations (≤ 0.5 μg/mL) has been suggested to circumvent these problems. The main aim of this study was to investigate whether patients with systemic symptoms alleged to result from the presence of dental amalgam differ from healthy controls, with reference to in vitro lymphoproliferative responses to HgCl2 ≤ 0.5 μg/mL. Three different test protocols—lymphocyte transformation test (LTT) in micro- and macro-cultures, and the memory lymphocyte immunostimulation assay (MELISA®)—were used. Other immune parameters—such as a standard patch test for dental materials, the number of T- and B-lymphocytes, monocytes, granulocytes, and NK cells in peripheral blood, allergic symptoms, and predisposition-were also investigated. Twenty-three amalgam patients, 30 healthy blood donors with amalgam, ten healthy subjects without amalgam, and nine patients with oral lichen planus (OLP) adjacent to dental amalgam and a positive patch test to Hg0 were tested. None of the investigated immune parameters revealed any significant differences between amalgam patients and controls. The sensitivity of in vitro lymphocyte proliferation ranged from 33 to 67%, with the OLP patients as a positive control group, and the specificity from 0 to 70% for healthy controls with a negative patch test to Hg°. Thus, despite the use of HgCl2 ≤ 0.5 μg/mL, a high frequency of positive results was obtained among healthy subjects with or without dental amalgam. Consequently, in vitro lymphocyte proliferation with HgCl2 cannot be used as an objective marker for mercury allergy in dental amalgam-bearers.
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