RESUMO
Bullous pemphigoid (BP) is characterized by substantial skin and blood eosinophilia as well as intensive pruritus. Since the pruritogenic cytokine interleukin (IL)-31 is increased in inflammatory skin diseases the aim of this study was to determine whether IL-31 plays a role in BP. Using immunofluorescence, IL-31 expression was analysed in eosinophils derived from blister fluids and skin from patients with BP and IL-31 levels in blister fluids, serum and culture supernatants were determined by enzyme-linked immunoassay (ELISA). High levels of IL-31 expression were observed in BP blister fluids, but they were only marginally elevated in BP serum compared with healthy controls. Eosinophils from either BP blister fluids or skin biopsies showed strong expression of IL-31. Furthermore, peripheral blood eosinophils from patients with BP, but not healthy controls, released high levels of IL-31, reflecting those in blister fluids. In conclusion, eosinophils are a major source of IL-31 in BP and this cytokine may contribute to itch in patients with BP.
Assuntos
Eosinofilia/imunologia , Eosinófilos/imunologia , Interleucinas/imunologia , Dermatopatias Vesiculobolhosas/imunologia , Pele/imunologia , Urticária/imunologia , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Células Cultivadas , Eosinofilia/sangue , Eosinofilia/diagnóstico , Eosinófilos/metabolismo , Feminino , Imunofluorescência , Humanos , Interleucinas/sangue , Masculino , Pessoa de Meia-Idade , Prurido/imunologia , Pele/metabolismo , Dermatopatias Vesiculobolhosas/sangue , Dermatopatias Vesiculobolhosas/diagnóstico , Regulação para Cima , Urticária/sangue , Urticária/diagnósticoRESUMO
Bullous pemphigoid (BP) is an autoimmune blistering skin disease that is more common in elderly individuals. The aim of this study was to determine the functional activity of eosinophils in patients with BP compared with healthy donors. Blood, skin and blister-derived eosinophils were strongly activated in patients with BP, seen by increased surface expression of CD69 compared with controls. CD11b was also increased in BP blood eosinophils, which may explain the striking accumulation of eosinophils in BP (1×106 per ml blister fluid). Furthermore, CCL26 was expressed by activated eosinophils in BP skin and in blister fluid. BP eosinophils also released IL-6, IL-8 and IL-1α in BP blister fluids. Apoptosis in cultivated BP eosinophils was increased and accompanied by enhanced surface externalization of CD95. Caspase 3 positive eosinophils in lesional BP skin and blister fluid also showed the initiation of apoptosis. These results reveal novel pathophysiological aspects of BP, with a strong activation pattern and increased apoptosis of eosinophils in the peripheral blood, skin and blister fluids.