The Angiostrongylus vasorum Excretory/Secretory and Surface Proteome Contains Putative Modulators of the Host Coagulation.

Nina Gillis-Germitsch,Manuela Schnyder,Lucienne Tritten,Lars M Asmis,Tobias Kockmann

doi:10.3389/fcimb.2021.753320

Abstract

Angiostrongylus vasorum is a cardiopulmonary nematode of canids and is, among others, associated with bleeding disorders in dogs. The pathogenesis of such coagulopathies remains unclear. A deep proteomic characterization of sex specific A. vasorum excretory/secretory proteins (ESP) and of cuticular surface proteins was performed, and the effect of ESP on host coagulation and fibrinolysis was evaluated in vitro. Proteins were quantified by liquid chromatography coupled to mass spectrometry and functionally characterized through gene ontology and pathway enrichment analysis. In total, 1069 ESP (944 from female and 959 from male specimens) and 1195 surface proteins (705 and 1135, respectively) were identified. Among these were putative modulators of host coagulation, e.g., von Willebrand factor type D domain protein orthologues as well as several proteases, including serine type proteases, protease inhibitors and proteasome subunits. The effect of ESP on dog coagulation and fibrinolysis was evaluated on canine endothelial cells and by rotational thromboelastometry (ROTEM). After stimulation with ESP, tissue factor and serpin E1 transcript expression increased. ROTEM revealed minimal interaction of ESP with dog blood and ESP did not influence the onset of fibrinolysis, leading to the conclusion that Angiostrongylus vasorum ESP and surface proteins are not solely responsible for bleeding in dogs and that the interaction with the host’s vascular hemostasis is limited. It is likely that coagulopathies in A. vasorum infected dogs are the result of a multifactorial response of the host to this parasitic infection.

Highlights

Angiostrongylus vasorum is a cardiopulmonary nematode of canids and is focally endemic in Europe, South America and Canada (Koch and Willesen, 2009; Jefferies et al, 2010; Priest et al, 2018)
This study reports the results of a deep characterization of A. vasorum proteins expressed at the hostparasite interface, namely excretory/ secretory proteins (ESP) and cuticular surface proteins, and investigates how ESP may interact with the host and lead to the onset of coagulation disorders
This study presents the results of the first proteomic analysis of A. vasorum ESP and cuticular surface proteins and discusses putative interactors with host coagulation or host immune response

Summary

Introduction

Angiostrongylus vasorum is a cardiopulmonary nematode of canids and is focally endemic in Europe, South America and Canada (Koch and Willesen, 2009; Jefferies et al, 2010; Priest et al, 2018). Bleeding dogs are usually hypocoagulable and show hyperfibrinolysis (Adamantos et al, 2015; Sigrist et al, 2017). Bleeding has been associated with alteration of various coagulation parameters and was attributed to thrombocytopenia, increased or decreased anti- or procoagulant factor activity, or disseminated intravascular coagulation (DIC) (Schelling et al, 1986; Ramsey et al, 1996; Adamantos et al, 2015; Glaus et al, 2016; Sigrist et al, 2017). A recent study conducted on sera of experimentally infected dogs showed that the complement and coagulation pathways were significantly affected over the course of infection, with reduced levels of relevant coagulation components (Tritten et al, 2021)

Methods

Results

Discussion

Conclusion