Pulmonary immune responses induced in BALB/c mice by Paracoccidioides brasiliensis conidia

Pulmonary Paracoccidioidomycosis: Clinical, Immunological and Histopathological Aspects

“…In vivo studies failed to detect nitric oxide (NO) production or inducible nitric oxide synthase (iNOS, the enzyme responsible for NO production) during the early days post-challenge in the lungs of mice infected with P. brasiliensis. Interestingly, as will be described below, a higher expression of iNOS was observed in the late periods of infection (González et al, 2008d). In additional studies, we observed an increase of in situ lysozyme expression (PMN and Ms) in the lungs of mice infected with P. brasiliensis conidia during the first 4 days post-challenge.…”

“…In addition, the in vivo administration of aminoguanidine (a highly specific inhibitor of iNOS) to P. brasiliensis-infected and noninfected mice induced in the former a significant reduction of their survival in comparison with negative control mice. These results suggest that during the chronic stages (12-17 weeks post-infection), the NO system played an important protective role against fungal infection (González et al, 2008d). This effect has also been observed in a model of latent tuberculosis (Flynn et al, 1998).…”

“…We developed an immunohistochemical stain for iNOS (NOS2) and observed that this enzyme was expressed mainly in vivo by the epithelioid histiocytes, with its maximal expression occurring 12 weeks after infection (González et al, 2008d). The expression of iNOS correlated significantly (r=0.77891) with the number of granulomas present in the pulmonary parenchyma (González et al, 2008d), suggesting that at this stage iNOS induction may depend on factors or mechanisms related to the environment in the granuloma (Goldman et al, 1996). In addition, the in vivo administration of aminoguanidine (a highly specific inhibitor of iNOS) to P. brasiliensis-infected and noninfected mice induced in the former a significant reduction of their survival in comparison with negative control mice.…”

Lung Diseases - Selected State of the Art Reviews

“…In this model, we have determined certain immune, histological and radiological aspects of pulmonary lesions by histopathology (early and chronic periods) (González et al, 2008a, b, c;Lopera et al, 2010Lopera et al, , 2011 as well as by high-resolution computed tomography-HRCT (chronic periods) . The local immune response has been measured by determining different cytokines in supernatants of pulmonary homogenates (González et al, 2003(González et al, , 2005b(González et al, , 2008dNaranjo et al, 2010). …”

A Centennial: Discovery of Paracoccidioides brasiliensis

“…Shikanai-Yasuda et al [14] survey published studies on cancer and paracoccidioidomycosis to highlight the importance of early and accurate diagnosis in clinical management. González et al [15] review studies aimed at mimicking initial host responses to P. brasiliensis conidia in a murine model that has yielded valuable insight about the development of fibrosis. The experimental study by Taborda et al [16] describes the important and yet previously unsuspected role of melanin pigmentation in virulence of P. brasiliensis.…”