RESUMO
BACKGROUND: Aspirin desensitization provides long-term clinical benefits. The exact mechanisms of aspirin desensitization are not clearly understood. OBJECTIVE: We sought to evaluate the effects of nonsteroidal anti-inflammatory drugs (NSAIDs) on T-cell activation of the IL-4 pathway in aspirin-sensitive patients with asthma and control subjects. METHODS: A total of 11 aspirin-sensitive patients with asthma, 10 aspirin-tolerant patients with asthma, and 10 controls without asthma were studied. PBMCs were stimulated with an anti-CD3 antibody and IL-4 or IL-12, with and without the presence of NSAIDs. The expression of phosphorylated signal transducers and activators of transcription 6 (pSTAT6), phosphorylated signal transducers and activators of transcription 4, and IL-4 was detected in CD4 T cells by flow cytometry. RESULTS: Stimulation with a combination of anti-CD3 and IL-4 induced pSTAT6 in CD4 T cells from all subjects. The induction of pSTAT6 was significantly higher in aspirin-sensitive patients with asthma than in controls subjects. The increase in pSTAT6 was inhibited in a dose-dependent manner by aspirin and indomethacin and minimally by sodium salicylate. This inhibition was strongest in aspirin-sensitive patients. Two-group comparisons showed significant differences in pSTAT6 inhibition by all concentrations of indomethacin and aspirin: between aspirin-sensitive and aspirin-tolerant groups and between aspirin-sensitive and control groups. No differences were found between aspirin-tolerant and control groups at all 3 concentrations. The inhibition of pSTAT6 was associated with reduced IL-4 expression. CONCLUSIONS: NSAIDs inhibited signal transducers and activators of transcription 6 signaling in CD4 T cells. This inhibition was significantly higher in aspirin-sensitive patients than in aspirin-tolerant subjects and was associated with reduced expression of IL-4. These findings have implications for clinical benefits of aspirin desensitization in aspirin-sensitive patients with asthma.
Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Aspirina/efeitos adversos , Hipersensibilidade a Drogas/imunologia , Hipersensibilidade a Drogas/metabolismo , Doenças Respiratórias/metabolismo , Fator de Transcrição STAT6/metabolismo , Transdução de Sinais/efeitos dos fármacos , Asma/etiologia , Asma/metabolismo , Estudos de Casos e Controles , Citocinas/biossíntese , Humanos , Fosforilação , Doenças Respiratórias/etiologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Linfócitos T/metabolismoRESUMO
Food allergies are an important medical problem in Westernized countries. Allergy to peanuts is a dramatic example of a food allergy that tends to be particularly severe and long-lived. This article examines food allergy-specifically peanut allergy-from the perspective that tolerance to foods is a normal state, just as tolerance to self-proteins is a normal state. From this vantage point, loss of tolerance to foods in food-allergic individuals can be viewed as parallel to the loss of tolerance to self-proteins in those with autoimmune diseases. Although our knowledge base is far from satisfactory, there are important similarities in the immunologic abnormalities that are characteristic of both peanut allergy and several autoimmune diseases. Delineation of these similarities may open the door to new therapeutic approaches for the treatment of severe food allergies.