Paracoccidioides restrepiensis B339 (PS3) and P. lutzii LDR2 yeast cells and soluble components display in vitro hemolytic and hemagglutinating activities on human erythrocytes

Abstract

Paracoccidioidomycosis (PCM) is a systemic mycosis caused by thermodimorfic fungi of Paracoccidioides species complex. Several pathogenic fungi produce hemagglutinins and hemolysins, which are virulence factors involved in adhesion of pathogens to host tissues or cells and in destruction of erythrocytes. The present research investigated hemolytic and hemagglutinating activities of yeast cells and soluble components from P. restrepiensis (PS3; former P. brasiliensis B339) and P. lutzii (LDR2). Different concentrations of live and heat-killed yeast cells and soluble components from cell free antigen preparation (CFA) (native or heated - 56 and 100 °C, 30 min) were mixed with 1% human erythrocyte suspension. Yeast cells from both species caused hemolysis, but P. lutzii LDR2 was more hemolytic than P. restrepiensis B339, while the opposite phenomena occurred with soluble components in most conditions. Live or heat-killed yeast cells of both fungi agglutinated erythrocytes, but only heated soluble components from P. restrepiensis B339 showed hemagglutinating activity. In conclusion, yeast cells of P. restrepiensis B339 and P. lutzii LDR2 produce hemolysins and hemagglutinins, which most likely are more restricted to yeast cells in P. lutzii LDR2 and are more released in soluble form byP. restrepiensis B339, requiring further study.

Gene expression of Paracoccidioides virulence factors after interaction with macrophages and fibroblasts

“…Virulence factors are essential for establishing an invasive fungal infection, including dimorphism, host cell adhesion, cell wall composition, and hydrolytic enzyme production. (16,17,18,19,20,21,40) Another aspect of this disease is pulmonary fibrosis, which is char- acterised by excessive deposition of collagen and extracellular matrix components that results in pathological remodeling of the pulmonary architecture. (40) In this study, the expression of six genes in the Y and M forms of Pb18 and Pb01 after infection of two different cell types was determined using qPCR.…”

“…Various components of Paracoccidioides spp., such as adhesins and others, may play a relevant role in pathogenesis. 16 , 17 , 18 , 19 , 20 , 21 de Oliveira et al 22 evaluated the gene expression of different adhesins, including 14-3-3 protein, GP43, enolase (ENO), glyceraldehyde 3-phosphate dehydrogenase (GAPDH), triosephosphate isomerase (TPI), and malate synthase (MLS), after mice infection with P. brasiliensis and P. lutzii . 22 The study found differences among the two species, and that 14-3-3 and ENO showed the highest expression .…”

“…The majority of the studies on fungal-host interactions have been performed on the Y form of the fungus. 21 , 35 , 36 , 37 However, to study the early stage of the disease and fungal adaptation to the host’s conditions, it is best to comparatively study the M and Y forms. Thus, this study aimed to compare virulence gene expression between the M and Y forms of P. brasiliensis (Pb18) and P. lutzii (Pb01), using quantitative polymerase chain reaction (qPCR) before and after infection of alveolar macrophages and human lung fibroblasts.…”

In vitro evaluation of the hemolytic activity of clinical and environmental isolates from dermatophyte fungi

“…As hemolisinas são exotoxinas de efeito citotóxico nas membranas dos eritrócitos e células fagocíticas, com capacidade de lisar os glóbulos vermelhos e liberar ferro, requerido no crescimento fúngico, contribuindo para a estratégia de sobrevivência durante infecções oportunistas (Aktas & Yıgıt, 2015), sendo relatadas em fungos como Histoplasma capsulatum, Candida albicans, Malassezia spp., Paracoccidioides spp. e Cryptococcus neoformans (Cezar-dos-Santos et al, 2018;Mohammadi et al, 2020;Salvin, 1951;Tee et al, 2019).…”