The relation between FoxP3⁺ regulatory T cells and fungal density in oral paracoccidioidomycosis: a preliminary study

Regulatory T (Treg) cells may play an important role in the pathogenesis of paracoccidioidomycosis (PCM), but data on the role of Treg cells in the context of oral PCM are still scarce. The objectives of this study were to investigate the density of FoxP3(+) T regulatory cells in oral PCM and to correlate the results with the density of Paracoccidioides brasiliensis in the lesions. Cases of chronic oral PCM seen between 2000 and 2008 were included in this study. The diagnosis of all lesions was confirmed with histopathological examination and Grocott-Gomori staining. The quantitative analysis of the viable fungi was conducted in all cases with Grocott-stained slides. Treg cells were identified using antibodies against FoxP3. Pearson correlation coefficient was used to test the correlation between the density of fungi and Treg cells. Results were considered significant when P < 0.05. A total of 11 cases of oral PCM were obtained. There was a positive correlation between fungal density and FoxP3(+) Treg cells density in oral lesions, however, without statistical significance. A positive relation between Treg cells and fungal density was seen in oral PCM. Further studies are required to further elucidate the role of these cells in the pathogenesis of oral PCM, as well the clinical significance of these findings.