Open AccessImmunolocalization of IFN ‐gamma in the lesions of resistant and susceptible mice to P aracoccidioides brasiliensis infection
Author(s) -
Nishikaku Angela Satie,
Molina Raphael Fagnani Sanchez,
Albe Bernardo Paulo,
Cunha Cláudia da Silva,
Scavone Renata,
Pizzo Célia Regina Pinto,
Camargo Zoilo Pires,
Burger Eva
Publication year - 2011
Publication title -
fems immunology & medical microbiology
Language(s) - English
Resource type - Journals
eISSN - 1574-695X
pISSN - 0928-8244
DOI - 10.1111/j.1574-695x.2011.00851.x
Subject(s) - paracoccidioides brasiliensis , paracoccidioidomycosis , biology , granuloma , virulence , paracoccidioides , interferon gamma , microbiology and biotechnology , staining , immunity , ratón , mycosis , immunology , pathology , cytokine , immune system , medicine , biochemistry , genetics , gene
Abstract The important role of interferon‐gamma ( IFN ‐γ) in protective immunity in mycosis is well established, except for its participation in fungal granulomas. Herein, we employ immunohistochemical reactions to describe the in situ localization of IFN ‐γ in granulomas of susceptible ( B 10. A ) and resistant ( A / J ) mice to infection with P aracoccidioides brasiliensis ( P b). After infection with the highly virulent P b18, IFN ‐γ‐positive lymphomononuclear cells were localized mainly at the periphery of granulomas in both mouse strains. The numbers of positive cells found in compact granulomas of A / J mice increased significantly from 15 to 120 days postinfection. At this time, significantly more positive cells were detected in the compact granulomas of resistant mice than in the loose, multifocal lesions of the susceptible ones. In infection with the slightly virulent P b265, the same pattern of IFN ‐γ localization was found as in P b18 infection, but there was decreased staining at 120 days due to the presence of only residual lesions in both mouse strains. The marked IFN ‐γ staining observed in the granulomas of resistant mice at the later stage of P b infection confirms its importance in fungal dissemination control, and suggests a contribution to the development of paracoccidioidal granuloma.