Plasma proteomic profiles differ between European and North American myotid bats colonized by Pseudogymnoascus destructans.

Alexander M Hecht‐Höger,Beate C Braun,Angelika Meschede,Gábor Á Czirják,Rüdiger Krahe,Christian C Voigt,Eberhard Krause,Alex D Greenwood

doi:10.1111/mec.15437

Abstract

Emerging fungal diseases have become challenges for wildlife health and conservation. North American hibernating bat species are threatened by the psychrophilic fungus Pseudogymnoascus destructans (Pd) causing the disease called white-nose syndrome (WNS) with unprecedented mortality rates. The fungus is widespread in North America and Europe, however, disease is not manifested in European bats. Differences in epidemiology and pathology indicate an evolution of resistance or tolerance mechanisms towards Pd in European bats. We compared the proteomic profile of blood plasma in healthy and Pd-colonized European Myotis myotis and North American Myotis lucifugus in order to identify pathophysiological changes associated with Pd colonization, which might also explain the differences in bat survival. Expression analyses of plasma proteins revealed differences in healthy and Pd-colonized M.lucifugus, but not in M.myotis. We identified differentially expressed proteins for acute phase response, constitutive and adaptive immunity, oxidative stress defence, metabolism and structural proteins of exosomes and desmosomes, suggesting a systemic response against Pd in North American M.lucifugus but not European M.myotis. The differences in plasma proteomic profiles between European and North American bat species colonized by Pd suggest European bats have evolved tolerance mechanisms towards Pd infection.

Highlights

The comparative expression analysis of plasma proteins between healthy and Pseudogymnoascus destructans (Pd)-colonized European M. myotis did not reveal different levels of protein expression. This is in agreement with the lack of pathological changes associated with the Pd-colonization and the lack of mortality in M. myotis from Pd infection (Davy et al, 2017; Johnson et al, 2015; Lilley et al, 2019; Wibbelt et al, 2010)
Of the eleven differentially expressed protein spots identified in North American M. lucifugus, MS analysis yielded protein IDs from eight spots that were linked to physiological mechanisms including acute phase response (A2M-like, TF, PF chains α, β, γ), constitutive innate immunity (C3-like), immune gene products (IGLL5, IGHV4OR15-8), oxidative stress control (6PGD, DJ-1-X1, AMBP-X1), metabolism (SIAT8-F, MAT2) and other physiological functions (ACT2, TB-β-2B-like-X1, 14-3-3 protein, DP, JPG-X1, Hb-β-like)
Host response against fungi is initiated by the recognition of fungal proteins by epithelial and innate immune cells resulting in the activation of the immune system through the production of inflammatory cytokines (Romani, 2011)

Summary

Introduction

To evaluate the expression pattern of protein spots separated by 2-D DIGE for healthy and Pd-colonized individuals, sample gels were analysed using the Delta2D software (DECODON, Germany). According to analysed expression profiles proteins spots with a fold change difference of ≥1.5 and a statistical significance of p < .05 between healthy and Pd-colonized individuals were picked for protein identification.

Results

Conclusion