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Background: Paracoccidioidomycosis (PCM) is a systemic mycosis with high prevalence in Latin America that is caused by thermodimorphic fungal species of the Paracoccidioides genus., Objectives: In this study, we used quantitative polymerase chain reaction (qPCR) to investigate the expression of genes related to the virulence of Paracoccidioides brasiliensis (Pb18) and P. lutzii (Pb01) strains in their mycelial (M) and yeast (Y) forms after contact with alveolar macrophages (AMJ2-C11 cell line) and fibroblasts (MRC-5 cell line)., Methods: The selected genes were those coding for 43 kDa glycoprotein (gp43), enolase, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), 14-3-3 protein (30 kDa), phospholipase, and aspartyl protease., Findings: In the Pb18 M form, the aspartyl protease gene showed the highest expression among all genes tested, both before and after infection of host cells. In the Pb18 Y form after macrophage infection, the 14-3-3 gene showed the highest expression among all genes tested, followed by the phospholipase and gp43 genes, and their expression was 50-fold, 10-fold, and 6-fold higher, respectively, than that in the M form. After fibroblast infection with the Pb18 Y form, the 14-3-3 gene showed the highest expression, followed by the phospholipase and aspartyl protease genes, and their expression was 25-fold, 10-fold, and 10-fold higher, respectively, than that in the M form. Enolase and aspartyl protease genes were expressed upon infection of both cell lines. After macrophage infection with the Pb01 Y form, the 14-3-3 gene showed the highest expression, followed by the phospholipase and aspartyl protease genes, and their expression was 18-fold, 12.5-fold, and 6-fold higher, respectively, than that in the M form., Main Conclusions: In conclusion, the data show that the expression of the genes analysed may be upregulated upon fungus-host interaction. Therefore, these genes may be involved in the pathogenesis of paracoccidioidomycosis.

BACKGROUND Paracoccidioides spp. causes paracoccidioidomycosis (PCM), an important and frequent systemic mycosis that occurs in Latin America. The infectious process begins with contact between the fungus and lung cells, and the molecular pattern of this interaction is currently poorly understood. MicroRNAs (miRNAs) are small non-coding RNAs that regulate the gene expression in many biological processes, including in the infections. OBJECTIVE This study aimed to analyse the expression of miRNAs in lung cells as response to infection by Paracoccidioides spp. METHODS A quantitative real-time polymerase chain reaction (RT-qPCR) based screening was employed to verify differentially expressed miRNAs in human lung cells infected with three different species; Paracoccidioides lutzii, Paracoccidioides americana, and Paracoccidioides brasiliensis. Furthermore, the in silico predictions of target genes and pathways for miRNAs were obtained. FINDINGS The results showed that miRNAs identified in the lung cells were different according to the species studied. However, based on the predicted targets, the potential signaling pathways regulated by miRNAs are common and related to adhesion, actin cytoskeleton rearrangement, apoptosis, and immune response mediated by T cells and TGF-β. MAIN CONCLUSIONS In summary, this study showed the miRNAs pattern of epithelial cells in response to infection by Paracoccidioides species and the potential role of these molecules in the regulation of key pathogenesis mechanisms of PCM.

Paracoccidioides brasiliensis is the cause of paracoccidioidomycosis, one of the most important systemic mycoses in Latin America. Human disease has been observed in a limited geographic and ecological niche, and it is attributed to exposure to the fungus in soil. Most primary infections are subclinical, as the infection is contained by the host mainly through cell-mediated immune response. However, as the fungus has the ability to survive in a dormant state for long periods, an impairment of the immune response may lead to reactivation and clinical disease. Surprisingly, paracoccidioidomycosis has rarely been reported in transplanted patients. The aim of this communication is to report a case occurring in a kidney recipient in an acute clinical form immediately after transplantation, and to review the available information on previously reported cases., (© 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Paracoccidioidomycosis is a systemic mycosis endemic to Latin America, with Paracoccidioides brasiliensis and P. lutzii being the causal agents of this disorder. Several issues have been raised in the 100 years since its discovery and in this article we discuss features of this fascinating fungal pathogen, including its biology, eco-epidemiology and aspects of its pathogenicity. We also consider some of its virulence determinants, the most recent advances in the study of its metabolic pathways and the molecular and genetic research tools developed for this research. We also review the animal models used to study host-fungal interactions and how the host defence mechanisms against this pathogen work., (Copyright © 2015 John Wiley & Sons, Ltd.)

Paracoccidioidomycosis is a subacute or chronic systemic mycosis caused by Paracoccidioides brasiliensis, a soil saprophyte and thermally dimorphic fungus. The disease occurs mainly in rural workers in Latin America and is the most frequent endemic systemic mycosis in many countries of South America, where almost 10 million people are believed to be infected. Paracoccidioidomycosis should be regarded as a disease of travelers outside the endemic area. The primary pulmonary infection is subclinical in most cases, and individuals may remain infected throughout life without ever developing clinical signs. A small proportion of patients present with clinical disease. The lungs are frequently involved, and the pulmonary clinical manifestations must be differentiated from many other infectious and noninfectious conditions. Diagnosis should be based on epidemiological, clinical, and microbiological data. Effective treatment regimens are available to control the fungal infection, but most patients develop fibrotic sequelae that may severely hamper respiratory and adrenal function and the patient's well-being., (© Thieme Medical Publishers.)

Paracoccidioides brasiliensis is a dimorphic fungus that is the causative agent of paracoccidioidomycosis, the most important prevalent systemic mycosis in Latin America. Recently, the existence of three genetically isolated groups in P. brasiliensis was demonstrated, enabling comparative studies of molecular evolution among P. brasiliensis lineages. Thirty-two gene sequences coding for putative virulence factors were analyzed to determine whether they were under positive selection. Our maximum likelihood-based approach yielded evidence for selection in 12 genes that are involved in different cellular processes. An in-depth analysis of four of these genes showed them to be either antigenic or involved in pathogenesis. Here, we present evidence indicating that several replacement mutations in gp43 are under positive balancing selection. The other three genes (fks, cdc42 and p27) show very little variation among the P. brasiliensis lineages and appear to be under positive directional selection. Our results are consistent with the more general observations that selective constraints are variable across the genome, and that even in the genes under positive selection, only a few sites are altered. We present our results within an evolutionary framework that may be applicable for studying adaptation and pathogenesis in P. brasiliensis and other pathogenic fungi.

Paracoccidioides brasiliensis is the fungus agent of paracoccidioidomycosis, a chronic systemic disease prevalent in Latin America. The aim of the present work was to evaluate the protection elicited by the immunization of BALB/c mice with radioattenuated yeast cells of P. brasiliensis. The immunization promoted a long lasting protection against highly infective yeast forms of P. brasiliensis. A 99.5% decrease in CFUs recovery was verified 90 days post challenge. At the same time the levels of IgG2a and IFN-gamma were high while a very low production of IL-10 and IL-5 was verified, suggesting that a Th1 pattern was dominant. This work shows the potential of radioattenuated yeast cells for the development of vaccines against fungi infections.

Paracoccidioides brasiliensis is the causative agent of paracoccidioidomycosis, a systemic mycosis endemic to Latin America. In this paper we review clinical, therapeutic and immunological aspects of the disease, as well as the biology and ecology of the fungus, restricting the review to the period 1989-1992.