Galleria mellonella as an insect model for P. destructans, the cause of White-nose Syndrome in bats

Abstract

Pseudogymnoascus destructans is the fungal pathogen responsible for White-nose Syndrome (WNS), a disease that has killed millions of bats in North America over the last decade. A major obstacle to research on P. destructans has been the lack of a tractable infection model for monitoring virulence. Here, we establish a high-throughput model of infection using larvae of Galleria mellonella, an invertebrate used to study host-pathogen interactions for a wide range of microbial species. We demonstrate that P. destructans can kill G. mellonella larvae in an inoculum-dependent manner when infected larvae are housed at 13°C or 18°C. Larval killing is an active process, as heat-killed P. destructans spores caused significantly decreased levels of larval death compared to live spores. We also show that fungal spores that were germinated prior to inoculation were able to kill larvae 3–4 times faster than non-germinated spores. Lastly, we identified chemical inhibitors of P. destructans and used G. mellonella to evaluate these inhibitors for their ability to reduce virulence. We demonstrate that amphotericin B can effectively block larval killing by P. destructans and thereby establish that this infection model can be used to screen biocontrol agents against this fungal pathogen.

Culture Degeneration Reduces Sex-Related Gene Expression, Alters Metabolite Production and Reduces Insect Pathogenic Response in Cordyceps militaris

“…The greater wax moth, Galleria mellonella (Lepidoptera: Pyralidae), has been used as an infection model for a wide range of fungal pathogens (e.g., [ 14 , 15 , 16 , 17 ]). G. mellonella caterpillars are easy to maintain under laboratory conditions and can be used for injection by hand owing to their large size (reaching approximately 2 cm in length) [ 18 ].…”

A common partitivirus infection in United States and Czech Republic isolates of bat white-nose syndrome fungal pathogen Pseudogymnoascus destructans

“…More in-depth experiments will be needed to discern the outcome of PdPV-1 infection on P. destructans phenotype and virulence. These investigations will be facilitated by the recent availability of a molecular tool kit and experimental infection model of P. destructans 46 – 51 .…”

Isolation of Bacterial and Fungal Microbiota Associated with Hermetia illucens Larvae Reveals Novel Insights into Entomopathogenicity

“…In order to achieve a comparable infection dose with the filamentous ascomycete F. solani, YPD agar plates were inoculated with a disc (0.6 cm) of an actively growing, one-week-old F. solani culture, and incubated at C for 12 days until sporulation occurred. For infection, F. solani conidia were released and harvested by rubbing the surface of plates covered with extraction solution (0.9% NaCl, 0.05% Tween-20) using a sterile Drigalski spatula [35]. Spores were separated completely from larger fragments of the hyphae by glass wool filtration, followed by two washing steps similar to the bacteria procedure and resuspended in 1 mL 0.9% NaCl solution.…”