AUTHOR=Pruksaphon Kritsada , Nosanchuk Joshua D. , Thammasit Patcharin , Pongpom Monsicha , Youngchim Sirida 

TITLE=Interaction of Talaromyces marneffei with free living soil amoeba as a model of fungal pathogenesis

JOURNAL=Frontiers in Cellular and Infection Microbiology

VOLUME=12

YEAR=2022

URL=https://www.frontiersin.org/journals/cellular-and-infection-microbiology/articles/10.3389/fcimb.2022.1023067

DOI=10.3389/fcimb.2022.1023067

ISSN=2235-2988

ABSTRACT=<p><italic>Talaromyces</italic> (<italic>Penicillium</italic>) <italic>marneffei</italic> is an important dimorphic mycosis endemic in Southeast Asia and Southern China, but the origin and maintenance of virulence traits in this organism remains obscure. Several pathogenic fungi, including <italic>Cryptococcus neoformans</italic>, <italic>Aspergillus fumigatus, Blastomyces dermatitidis</italic>, <italic>Sporothrix schenckii</italic>, <italic>Histoplasma capsulatum</italic> and <italic>Paracoccidioides</italic> spp. interact with free living soil amoebae and data suggests that fungal pathogenic strategies may emerge from environmental interactions of these fungi with ubiquitous phagocytic microorganisms. In this study, we examined the interactions of <italic>T. marneffei</italic> with the soil amoeba <italic>Acanthamoeba castellanii</italic>. <italic>T. marneffei</italic> was rapidly ingested by <italic>A. castellanii</italic> and phagocytosis of fungal cells resulted in amoeba death after 24 h of contact. Co-culture also resulted in a rapid transition for conidia to the fission-yeast form. In addition, well-established virulence factors such as melanin and a yeast specific mannoprotein of <italic>T. marneffei</italic> were expressed during interaction with <italic>A. castellanii</italic> at 37°C. Our findings support the assumption that soil amoebae environmental predators play a role in the selection and maintenance of particular features in <italic>T. marneffei</italic> that impart virulence to this clinically important dimorphic fungus in mammalian hosts.</p>