Comparative Study of the Inflammatory Response in Experimental Paracoccidioidomycosis: Histopathological and Immunohistochemical Profile in Balb/c, AIRmax, and AIRmin Mice

• Grant number: 25/21350-7
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: December 01, 2025
• End date: November 30, 2026
• Field of knowledge: Biological Sciences - Immunology - Cellular Immunology
• Principal Investigator: Luciane Alarcão Dias-Melicio
• Grantee: Isabela de Carvalho Tunes Terrin
• Host Institution: Faculdade de Medicina (FMB). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil

Abstract

Paracoccidioidomycosis (PCM) is a systemic mycosis endemic to Latin America, caused mainly by Paracoccidioides brasiliensis. This disease has a broad clinical spectrum, ranging from mild to severe forms, reflecting differences in the host's immune response. Among the body's defense mechanisms against the pathogen, neutrophils play a key role, whose intensity of activation can determine resistance or susceptibility to infection. Thus, murine models with different inflammatory profiles, such as AIRmax (high response) and AIRmin (low response), allow this variability to be reproduced experimentally. The objective of this study is to characterize histopathologically and immunohistochemically the lungs, liver, and spleen of Balb/C, AIRmax, and AIRmin mice infected with P. brasiliensis, correlating the inflammatory profile with granuloma formation, tissue damage, and cytokine expression (IL-8, TNF-¿, IFN-¿, IL-10, IL-4, and IL-17). To this end, infected organs will be collected at different times and analyzed to identify morphological changes and cytokine localization. It is expected that AIRmax will show greater containment of infection and organized granulomas, while AIRmin will exhibit greater tissue damage and fungal dissemination. The results will contribute to a better understanding of the immunopathogenesis of PCM and the role of neutrophils, in addition to strengthening the scholarship recipient's academic training in histological and immunological techniques.