RESUMO
BACKGROUND: Ivermectin (IVM) is widely used in both human and veterinary medicine to treat parasitic infections. Recent reports have suggested that IVM could also have anti-inflammatory properties. METHODS: Here, we investigated the activity of IVM in a murine model of atopic dermatitis (AD) induced by repeated exposure to the allergen Dermatophagoides farinae, and in standard cellular immunological assays. RESULTS: Our results show that topical IVM improved allergic skin inflammation by reducing the priming and activation of allergen-specific T cells, as well as the production of inflammatory cytokines. While IVM had no major impact on the functions of dendritic cells in vivo and in vitro, IVM impaired T-cell activation, proliferation, and cytokine production following polyclonal and antigen-specific stimulation. CONCLUSION: Altogether, our results show that IVM is endowed with topical anti-inflammatory properties that could have important applications for the treatment of T-cell-mediated skin inflammatory diseases.
Assuntos
Alérgenos/imunologia , Dermatite Atópica/imunologia , Ivermectina/administração & dosagem , Administração Tópica , Animais , Antígenos de Dermatophagoides/imunologia , Linhagem Celular , Citocinas/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Dermatite Atópica/tratamento farmacológico , Dermatite Atópica/patologia , Modelos Animais de Doenças , ELISPOT , Proteína do X Frágil da Deficiência Intelectual/metabolismo , Humanos , Mediadores da Inflamação/metabolismo , Ativação Linfocitária/imunologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Camundongos Knockout , Receptores Purinérgicos P2X4/metabolismo , Subpopulações de Linfócitos T/efeitos dos fármacos , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismoRESUMO
BACKGROUND/OBJECTIVES: Probiotics are defined as 'living micro-organisms that when administered in adequate amounts confer a health benefit to the host'. Different probiotic strains have been investigated for beneficial effects on allergic disorders. The purpose of the current study was to evaluate the effect of orally administering the probiotic Nestlé culture collection (NCC)2818 Bifidobacterium lactis strain on immune parameters and nasal symptom scores in subjects suffering from seasonal allergic rhinitis (SAR). SUBJECTS/METHODS: The study was a double-blinded, parallel, randomized placebo-controlled trial conducted during the peak of the pollen season. Adult subjects with clinical history of SAR and positive skin prick test to grass pollen were recruited. The subjects received B. lactis NCC2818 or placebo for 8 weeks and completed symptom questionnaires every week. Whole blood was collected at baseline (V1), 4 weeks (V2) and 8 weeks (V3) to measure immune parameters. RESULTS: Concentrations of Th-2 cytokines, secreted by stimulated blood lymphocytes, were significantly lower in the probiotic group compared with the placebo group at V3 (interleukin (IL)-5, P=0.016; IL-13, P=0.005). Total nasal symptom scores were significantly lower in the second month of the study (weeks 5-8) in the probiotic group compared with the placebo group (P=0.03). Also, percentages of activated CD63 expressing basophils were significantly lower in the probiotic group at V2 (P=0.02). CONCLUSIONS: Oral administration of the probiotic NCC2818 mitigates immune parameters and allergic symptoms during seasonal exposure. These promising results warrant that B. lactis NCC2818 be investigated further in large-scale trials for management of respiratory allergy.