BackgroundIL-6 is a pro-inflammatory cytokine which has many well-defined effects. Its synthesis and release from mononuclear cells of drug-sensitized patients was related before to in vitro drug-allergy diagnostics but has not yet been studied in detail.MethodsThe specific release of preformed IL-6 from peripheral blood mononuclear cells (PBMC) after 20 minutes incubation with 0.15–0.5 μM of pure drugs was measured in two groups of drug-allergy suspected donors (159) and respective controls (48). IL-6, TNF-alpha, IL-2, IL-4, IFN-gamma have been measured from cell supernatants by ELISA or by cytometric bead assay. Epicutaneous, intradermal and systemic provocation tests were performed to prove or disprove culprit substances (203 in vivo against 482 in vitro tests). T-test (paired and unpaired); chi2 contingency table; Z statistics and McNemar’s test were used to evaluate results.ResultsConcanavalin A as positive control released IL-6 from PBMC in linear concentration and exponential time dependent fashion (up to 60 minutes) pointing to the existence of a preformed pool of this cytokine.Preformed IL-6 released at any of 4 standard drug dilutions tested, above 50% over their diluents’ levels significantly correlated with the patients’ history on drug-induced hypersensitivity symptoms and with in vivo tests.Sensitivity of 85.4% and specificity of 82.4% of the IL-6 release assay were found. The 20′ drop in release of TNF-alpha had no diagnostic importance; it has accompanied increased IL-6 release. IL-2, IL-4 and IFN-gamma were undetectable in 20 minutes supernatants. IL-6 release depended on the clinical phenotype but not on the eliciting drug(s) in the molecular mass range of 76–4000 Da. Reactivity of mononuclear cells at the lowest or at multiple drug test concentrations reflected clinical severity per diagnoses and according to area of skin involvement.ConclusionThis rapid test is applicable to detect a wide scale of drug hypersensitivity.

Luminol is a non-radical-specific amplifying molecule which produces light upon interaction with various reactive oxygen intermediates (ROIs). ROI production of rat peritoneal polymorphonuclear leukocytes (PMNLs) elicited by 2.3 microM formyl-methionyl-leucyl-phenylalanine (fMLP) results in a biphasic luminol-dependent chemiluminescence (LDCL) signal. Whereas ROIs are also produced intracellularly, as judged by flow cytometry, addition of non-membrane-permeable catalase reduces the first and second phases of the LDCL signal to around 3% and less than 3%, respectively. This suggests that in the case of fMLP-stimulated rat PMNLs, the LDCL signal is related to the ROIs in the extracellular medium and hydrogen peroxide has a key role in the formation of the LDCL signal. In the presence of the non-specific myeloperoxidase inhibitor Na-azide, the first phase of the LDCL signal decreases slightly (87+/-8%), while the second phase almost disappears (< 3%), indicating the myeloperoxidase dependence of the second phase. The hydroxyl radical scavenger histidine results in an 84+/-4% and a 71+/-4% decrease in the intensity of the first and second phases, respectively. Based on these data, it is concluded that hydrogen peroxide might be the source of hydroxyl radicals directly oxidizing luminol in the first phase of the LDCL signal, while in the second phase it serves as a substrate of myeloperoxidase in the peroxidation reaction of the luminol.

Objective: Current concept distinguishes between cross intolerance (non-immune) and single or multiple hypersensitivity based (immune) adverse reactions of non-steroidal anti-inflammatory drugs (NSAID) due to their potential to inhibit cyclooxygenase (COX) isoenzymes (COX-1, COX-2). Recently we described a rapid IL-6 release assay using blood mononuclear cells of patients with various clinical forms of drug hypersensitivity. Here we present data of a comprehensive analysis of the IL-6 release test and the classical IgE immuno-assay for their sensitivity in cases with adverse reactions to NSAIDs grouped according to the new clinical classification. Methods: Total and specific serum IgE against 9 different HSA coupled-NSAIDs were determined by manual ELISA tests (55 cases) and compared to drug-specific release from preformed IL-6 pool of PBMCs of patients sensitized to the same NSAIDs after short (20 ') incubation of 4 standardized concentrations (51 cases and 9 controls) and IL-6 measurement from their cell free supernatants including positive and negative intraassay controls. Results: The ratio of cross intolerant to specific hypersensitive (HS) cases was higher in the IgE group (and total IgE too,) than in the IL-6 release tested ones. There was no difference, however, in the overall ratio of early and accelerated plus late onset adverse events based on individual histories. Nine NSAIDs were tested in both groups which represented all major COX-1 inhibitors. The positivity of validated test results was double within the IL-6 tested group (65.4% vs. 36.9%). In some cases non-drug components of NSAID formulations were responsible for the observed (mainly) anaphylactic reactions. Positive results in both groups were scattered amongst cross intolerant and single to multiple hypersensitive (HS) subgroups. To our knowledge no comprehensive analysis had been performed before either on clinical phenotypes dependent IgE immunoassays or on NSAID-induced "early" Tcell activation after those specified adverse events. Conclusion: Specific HS and multiple non cross-reactive NSAID sensitizations exceeded non-immune reactions in both in vitro tested groups. Some intolerant patients revealed detectable ASA antibodies of IgE type. Preformed IL-6 release by PBMC was more sensitive than specific IgE immunoassays as an in vitro diagnostic tool. The results indicate that checking of non-drug components should be considered in allergy workups. ASA in vivo provocations need further standardization.

Superoxide dismutases are considered to be essential protective agent against radiation injury. Experiments were carried out to investigate the effect of extracellularly added SOD on the radiosensitivity of Bacillus megaterium spores. 120 micrograms/ml SOD had no effect on the radiosensitivity of Bacillus megaterium spores at different oxygen concentrations. Relative enzyme activity obtained at various oxygen concentrations indicating the lack of oxygen effect in the radiation-induced inactivation of SOD.

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