Failure of nitric oxide production by macrophages and decrease in CD4+ T cells in oral paracoccidioidomycosis: possible mechanisms that permit local fungal multiplication Falha na produção de óxido nítrico pelos macrófagos e diminuição de células T CD4+ na paracoccidioidomicose bucal: possíveis mecanismos que permitem a multiplicação fúngica local

• Published in: Revista do Instituto de Medicina Tropical de São Paulo
• Main Authors: Aline Carvalho Batista, Cleverson Teixeira Soares, Vanessa Soares Lara
• Format: Article in Journal/Newspaper
• Language: English
• Published: Universidade de São Paulo (USP) 2005
• Subjects: Paracoccidioidomycosis; Nitric oxide; Immune cells; Arctic medicine. Tropical medicine; RC955-962; Infectious and parasitic diseases; RC109-216; Arctic
• Online Access: https://doi.org/10.1590/S0036-46652005000500006; https://doaj.org/article/d47c590868124b76ae80880b63975f48

Paracoccidioidomycosis is a chronic granulomatous disease that induces a specific inflammatory and immune response. The participation of nitric oxide (NO), a product of the inducible nitric oxide synthase enzyme (iNOS), as an important fungicidal molecule against Paracoccidioides brasiliensis has been demonstrated. In order to further characterize the Oral Paracoccidioidomycosis (OP), we undertook an immunohistochemical study of iNOS+, CD45RO+, CD3+, CD8+, CD20+, CD68+ cells and mast cells. The samples were distributed in groups according to the number of viable fungi per mm². Our results showed weak immunolabeling for iNOS in the multinucleated giant cells (MNGC) and in most of the mononuclear (MN) cells, and the proportion of iNOS+ MN/MNGC cells in the OP were comparable to Control (clinically healthy oral tissues). Additionally, our analysis revealed a similarity in the number of CD4+ cells between the Control and the OP groups with higher numbers of fungi. These findings suggest that a low expression of iNOS and a decrease in the CD4+ T cells in OP may represent possible mechanisms that permit the local fungal multiplication and maintenance of active oral lesions. A paracoccidioidomicose é uma doença granulomatosa crônica que induz resposta inflamatória e imune específica. A participação do óxido nítrico (NO), produto da enzima óxido nítrico sintase induzível (iNOS), como uma importante molécula fungicida contra o fungo Paracoccidioides brasiliensis tem sido demonstrada. Com o objetivo de melhor caracterizar as lesões orais da paracoccidioidomicose (OP), propusemos estudo imunohistoquímico das células iNOS+ e das células CD45RO+, CD3+, CD8+, CD20+, CD68+ e mastócitos. As amostras foram distribuídas em grupos de acordo com o número de fungos viáveis por mm². Nossos resultados demonstraram leve imunomarcação para iNOS nas células gigantes multinucleadas (MNGC) e na maioria das células mononucleares (MN), e a proporção de células MN/MNGC iNOS+ na OP foi comparável a do grupo Controle (tecido bucal clinicamente ...