III). Targeting excretory/secretory products (ESP) of Echinococcus multilocularis in patient sera – an approach for novel biomarker discovery for early stage alveolar echinococcosis

E. multilocularis larval stage (vesicles) cultivated in vitro

The larval stage of the fox tapeworm Echinococcus multilocularis is responsible for the zoonotic life-threatening disease alveolar echinococcosis (AE). The number of human AE cases in different regions vary widely. Main hotspots are recorded in northern Asia, e.g., in particular in China (over 16000 cases annually) and Kyrgyzstan (around 200 new cases per year), while in Europe endemic areas are in Central Europe with around 150-200 new AE cases reported per annum (e.g., France, Germany, Switzerland), and in North America where most AE cases are reported from Alaska. According to recent reports, the distribution range of E. multilocularis is expanding, with new endemic areas being reported in recent years. It is also worth noting that the recorded prevalence of human AE is likely underestimated due to a combination of factors – e.g., disease remains asymptomatic for years (up to decades), availability of medical services, efforts focused on detecting the disease and whether AE cases are mandatory to report. Early diagnosis is crucial for the patient as it allows for more effective and less invasive treatment strategies. A number of sensitive and specific serological diagnostic tools have been developed for AE detection. Their diagnostic performance values are, however, typically evaluated for later stage AE, and it was recently reported that nearly 48% of confirmed early AE cases may present as false negatives in serological testing. The parasite interacts with the host by secreting a number of excretory/secretory products (ESP) to the surrounding tissue of its larval stage (vesicles), some of which act as immunogenic antigens. Correspondingly, in order to improve the early diagnosis, it is relevant to characterize the ESP products of the parasite. The main goal of this ongoing project is to characterize the ESP of the larval stage of E. multilocularis using a quantitative proteomics pipeline, which will lead to the selection of potential novel biomarkers. The highly abundant identified parasite proteins will be retrieved in patient sera by a targeted proteomics approach. As a result, the project would contribute to develop more sensitive tests for early AE diagnosis.

Institute members: Teivi Laurimäe (Postdoc), Philipp A. Kronenberg (PhD candidate), Ramon M. Eichenberger (Projekt Leader), Peter Deplazes (Project Leader)

External members: Jonas Grossmann (Bioinformatics, FGCZ, Switzerland), Peter Gehrig (FGCZ), Bernd Roschitzki (FGCZ)

Funding sources: IPZ