Cellular and humoral immune responses during intrathoracic paracoccidioidomycosis in BALB/c mice

• Published in: Comparative immunology, microbiology and infectious diseases microbiology and infectious diseases, 2009-12, Vol.32 (6), p.513-525
• Main Authors: Alves, Caio C.S, Azevedo, Ana L.S, Rodrigues, Michele F, Machado, Rachel P, Souza, Maria A, Machado, Marco A, Teixeira, Henrique C, Ferreira, Ana P
• Format: Article
• Language: English
• Subjects: Allergy and Immunology; Animals; Antibodies, Fungal; Antibody Formation; Antibody response; Biological and medical sciences; Blastomycoses and paracoccidioidomycosis; Chronic infection; Fundamental and applied biological sciences. Psychology; Granuloma - microbiology; Granuloma - pathology; Human mycoses; IFN-γ; IL-10; Immunity, Cellular; Immunoglobulin G - blood; Infection intrathoracique; Infectious Disease; Infectious diseases; Interferon-gamma - biosynthesis; Interleukin-10 - biosynthesis; Intrathoracic route; Lung - microbiology; Lung - pathology; Male; Medical sciences; Mice; Mice, Inbred BALB C; Microbiology; Miscellaneous; Mycology; Mycoses; Nitric Oxide - biosynthesis; Paracoccidioides - immunology; Paracoccidioides - isolation & purification; Paracoccidioides brasiliensis; Paracoccidioidomycosis; Paracoccidioidomycosis - immunology; Paracoccidioidomycosis - metabolism; Paracoccidioidomycosis - pathology; Paracoccidioïdomycose; Réponse anticorps; Thorax - microbiology; Thorax - pathology; Tropical mycoses
• ISSN: 0147-9571; 1878-1667
• DOI: 10.1016/j.cimid.2008.07.006

Abstract Paracoccidioidomycosis is a chronic infection that primarily affects the lungs. Here we investigated cellular and humoral immune responses after intrathoracic Paracoccidioides brasiliensis infection in BALB/c mice. P. brasiliensis -colony-forming units (CFUs), fungal DNA and granulomas in lungs increased progressively, peaking at day 90 postinfection (p.i.). IFN-γ production was highest on day 15 p.i., declining thereafter. The kinetics of the NO production was similar to that described for IFN-γ. In contrast, IL-10 increased from day 45 p.i. reaching a peak at day 90. Levels of serum IgG1 were higher than IgG2a between days 30 and 90 p.i. 30% of mice died by day 90 p.i. These data indicate that infection with P. brasiliensis by the intrathoracic route shows high IFN-γ and NO production at day 15 p.i., unable to control multiplication of fungi, which appears to be associated with a progressive increase in IL-10 and in the number and complexity of granulomas.