Free radicals as potential mediators of metal allergy: effect of ascorbic acid on lymphocyte proliferation and IFN-gamma production in contact allergy to Ni2+ and Co2+.
A possible free radical mechanism in metal allergy was investigated in peripheral blood mononuclear cell (PBMC) cultures from 6 subjects, contact allergic to Ni2+ and Co2+, and 6 control individuals. Ni2+ and Co(2+)-mediated free radical generation was studied with electron spin resonance spectroscopy. The immune response was characterized by cellular [methyl-3H]thymidine uptake and interferon-gamma (IFN-gamma) production Ni2+ and Co2+ (10-50 microM) significantly increased lymphocyte proliferation and IFN-gamma production in PBMC cultures from contact allergic subjects in comparison with cultures from controls. Inhibition of Co(2+)-mediated free radical generation by ascorbic acid did not influence cellular [methyl-3H]thymidine uptake and IFN production. Detectable amounts of free radicals were not obtained with Ni2+. We therefore conclude that it is unlikely that free radicals are involved in contact allergy to Ni2+ and Co2+.
Van Den Broeke
L T
LT
Department of Occupational Health, National Institute for Working Life, Solna, Sweden.
Gräslund
A
A
Larsson
P H
PH
Nilsson
J L
JL
Wahlberg
J E
JE
Scheynius
A
A
Karlberg
A T
AT
D000328:Adult; D001205:Ascorbic Acid / Q000494:pharmacology*; D016022:Case-Control Studies; D018929:Cell Culture Techniques; D003300:Copper / Q000009:adverse effects*; D017449:Dermatitis, Allergic Contact / Q000276:immunology*; D004578:Electron Spin Resonance Spectroscopy; D005260:Female; D005609:Free Radicals / Q000276:immunology; D006801:Humans; D007371:Interferon-gamma / Q000096:biosynthesis* / Q000187:drug effects; D008875:Middle Aged; D009000:Monocytes / Q000187:drug effects / Q000276:immunology*; D009532:Nickel / Q000009:adverse effects*; D010328:Patch Tests
D005609:Free Radicals; D003300:Copper; D009532:Nickel; D007371:Interferon-gamma; D001205:Ascorbic Acid