Candidiasis by Candida glabrata, Candida nivariensis and Candida bracarensis in Galleria mellonella: Virulence and Therapeutic Responses to Echinocandins.

Ainara Hernando-Ortiz,Guillermo Quindós,Elena Eraso,Estibaliz Mateo

doi:10.3390/jof7120998

Ainara Hernando-Ortiz, Guillermo Quindós + Show 2 more

Open Access

https://doi.org/10.3390/jof7120998

Copy DOI

Abstract

Candida albicans is the major etiological agent of invasive candidiasis but the increasing prevalence of emerging species of Candida, such as Candida glabrata and phylogenetically closely related species, Candida nivariensis and Candida bracarensis, requires special attention. Differences in virulence among these species and their therapeutic responses using in vivo non-mammalian models are scarcely analysed. The aim of this study was analyse the survival of G. mellonella and host-pathogen interactions during infection by C. glabrata, C. nivariensis and C. bracarensis. Moreover, therapeutic responses to echinocandins were also assessed in the G. mellonella model of candidiasis. These three species produced lethal infection in G. mellonella; C. glabrata was the most virulent species and C. bracarensis the less. Haemocytes of G. mellonella phagocytised C. bracarensis cells more effectively than those of the other two species. Treatment with caspofungin and micafungin was most effective to protect larvae during C. glabrata and C. nivariensis infections while anidulafungin was during C. bracarensis infection. The model of candidiasis in G. mellonella is simple and appropriate to assess the virulence and therapeutic response of these emerging Candida species. Moreover, it successfully allows for detecting differences in the immune system of the host depending on the virulence of pathogens.

Highlights

Three inocula were assayed to evaluate the virulence of the strains of C. glabrata, C. nivariensis and C. bracarensis observing that larval mortality was inoculum-dependent
(b) G. mellonella infection with C. glabrata NCPF 3203 the efficacies of these echinocandins against C. glabrata infection were strain-dependent (Table100 and Figure 5a,b). Candidiasis caused by both C. glabrata strains responded to MCF at the two concen90
Concentrations of 4 and 8 μg/g larva

Summary

Introduction

Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. There is a substantial change in the aetiology of candidiasis worldwide, with an increasing prevalence of non-Candida albicans species, such as Candida parapsilosis, Candida glabrata, Candida tropicalis, Candida krusei and Candida auris. C. glabrata is an emerging pathogen and the second cause of candidaemia in the USA, Canada, Australia and Northern and Eastern Europe. In Latin America, Africa, and the European Mediterranean countries such as Spain, candidiasis due to C. glabrata are the third most frequent, behind those caused by C. albicans and C. parapsilosis [1]. Candida bracarensis and Candida nivariensis are species phylogenetically close to C. glabrata that should be identified by molecular methods, including MALDI-TOF MS

Objectives

Results

Conclusion