The interaction between Sporothrix schenckii sensu stricto and Sporothrix brasiliensis with Acanthamoeba castellanii

Abstract

Summary Background Sporotrichosis is a group of zoonotic subcutaneous mycoses, found worldwide and caused by fungi belonging to the genus Sporothrix. Protozoans of the genus Acanthamoeba are widely distributed, and some species may be pathogenic and/or opportunistic. These organisms coexist in the same environment and may interact. Objectives This study determined the profile of interactions of S schenckii sensu stricto and S brasiliensis with A castellanii, using an in vitro co‐culture model to evaluate the intrinsic characteristics of the two Sporothrix species and A castellanii. Methods We compared the rate of phagocytosis of S schenckii sensu stricto and S brasiliensis by A castellanii; the viability of S schenckii sensu stricto and S brasiliensis after contact with A castellanii; the viability of the amoeba after contact with a fungal species; and the influence of S schenckii sensu stricto and S brasiliensis on the encystment process of A castellanii. Results The analyses indicated that A castellanii phagocytised both S schenckii and S brasiliensis, with significantly more S schenckii than S brasiliensis in the first two hours of contact. Our results showed a significant increase in conidia and hyphae count after 72 hours of co‐culture of A castellanii with S brasiliensis, and the amoebae lysed after they ingested the fungi, indicating that the fungi probably used the amoebae as a source of nutrition. Conclusions Our results were obtained in vitro and these organisms may not behave similarly in vivo; in vivo studies of co‐infections are necessary in order to gain a thorough understanding of this relationship.

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

“…For instance, the interactions of Cryptococcus neoformans and macrophages, slime molds ( Steenbergen et al., 2003 ), and amoebae ( Steenbergen et al., 2001 ) are remarkably similar, indicating that fungal pathogenic strategies may emerge from environmental interactions with phagocytic microorganisms. After this seminal work with C. neoformans , subsequent studies found that the interactions of A. castellanii and dimorphic fungi such as Histoplasma capsulatum , Blastomyces dermatitidis , Sporothrix spp., and Paracoccidioides spp., similarly reproduced interactions seen with macrophages ( Steenbergen et al., 2004 ; Singulani et al., 2018 ; Albuquerque et al., 2019 ; Lemos Tavares et al., 2020 ). A. castellanii not only serves as a host system for those dimorphic fungi, but also for Aspergillus fumigatus ( Van Waeyenberghe et al., 2013 ), Cryptococcus gattii ( Malliaris et al., 2004 ), and entomogenous fungi ( Bidochka et al., 2010 ).…”

Current Progress on Epidemiology, Diagnosis, and Treatment of Sporotrichosis and Their Future Trends

“…It is known that soil microbial composition can be altered due to deforestation, reflecting co-occurrence patterns among microorganism taxa, leading to ecological imbalance [ 170 , 171 ]. For example, soil amoebas (e.g., Acanthamoeba castellanii ) rapidly change the composition of the bacterial community in the soil [ 172 ], and it is well known that many of these protozoa interact with Sporothrix , predating the microorganism in the soil [ 173 , 174 ]. Therefore, it is expected that environmental stresses (e.g., higher temperatures, humidity, pH, etc.)…”

A history of over 40 years of potentially pathogenic free-living amoeba studies in Brazil - a systematic review

“…(184) Sixty-seven percent (39/58) of the auxiliary references describe investigations specific to ARMs. Fungi and FLA interactions addressed Trichophyton rubrum, (90) Fusarium, (85) Sporothrix, (185) Paracoccidioides spp., (186) and Cryptococcus species, (183,187,188) all associated with Acanthamoeba. Some of these reports highlight that fungi-FLA interactions in the environment mimic those found between fungi and host cells, possibly contributing to the development of virulence and immune escape strategies.…”