Comparison of cytokine secretion profiles provoked in mice by glutaraldehyde and formaldehyde

Background Glutaraldehyde and formaldehyde are commonly used sterilizing ag ents that are known skin sensitizers. There is some controversy, however, r egarding their capacity to cause respiratory allergy. The authors have demo nstrated previously that topical exposure of mice to chemical contact aller gens such as 2,4-dinitrochlorobenzene (DNCB) or respiratory allergens such as trimellitic anhydride (TMA) induces characteristic cytokine secretion pr ofiles consistent with the selective activation of T helper 1 (TH1)- and TH 2-type cells, respectively. Objective To investigate the quality of immune response provoked following topical exposure of mice to these materials. Methods BALB/c strain mice were exposed topically to 50% formaldehyde or to various concentrations of glutaraldehyde in acetone. Control animals were treated concurrently with the reference contact allergen DNCB (1% in aceton e:olive oil [AOO]) or with the reference respiratory sensitizer TMA (10% in AOO). Thirteen days after the initiation of exposure, draining lymph node cells (LNCs) were cultured for 13-120 h and cytokine content of supernatant s analysed by cytokine-specific enzyme-linked immunosorbent assay. Results DNCB-alpha and formaldehyde-activated LNCs produced high levels of the TH1-type cytokine interferon gamma, but little of the TH2-type products interleukins 4 and 10. TMA- and glutaraldehyde-stimulated LNCs displayed t he converse TH2-type pattern of cytokine expression. Conclusions These data are consistent with glutaraldehyde, but not formalde hyde, having significant potential to cause allergic sensitization of the r espiratory tract.