Progresses and challenges in Strongyloides spp. proteomics

Abstract

The availability of high-quality data of helminth genomes provided over the past two decades has supported and accelerated large-scale 'omics studies and, consequently, the achievement of a more in-depth molecular characterization of a number of pathogens. This has also involved Strongyloides spp. and since their genome was made available transcriptomics has been rather frequently applied to investigate gene expression regulation across their life cycle. Strongyloides proteomics characterization has instead been somehow neglected, with only a few reports performing high-throughput or targeted analyses associated with protein identification by tandem mass spectrometry. Such investigations are however necessary in order to discern important aspects associated with human strongyloidiasis, including understanding parasite biology and the mechanisms of host-parasite interaction, but also to identify novel diagnostic and therapeutic targets. In this review article, we will give an overview of the published proteomics studies investigating strongyloidiasis at different levels, spanning from the characterization of the somatic proteome and excretory/secretory products of different parasite stages to the investigation of potentially immunogenic proteins. Moreover, in the effort to try to start filling the current gap in host-proteomics, we will also present the first serum proteomics analysis in patients suffering from human strongyloidiasis. This article is part of the Theo Murphy meeting issue 'Strongyloides: omics to worm-free populations'.

Keywords: excretory/secretory product; immunoproteomics; proteomics; somatic proteome; strongyloidiasis.

Figure 1.

Results of host serum proteomics analysis applied to investigate samples from patients with strongyloidiasis (taken before treatment (BT) and 6 and 12 months after treatment) and uninfected controls. For each group n = 5 samples were analysed. (a) Volcano plot showing the differential abundance of the quantified proteins in the different samples. The dotted line on the y-axes represents 0.05 p-value threshold, while the dotted lines on the x-axes represent 0.83 and 1.2 FC thresholds. (b) (overleaf) Table summarizing proteins significantly differentially abundant in at least one of the three analysed comparisons. For each protein, the p-value and the fold change are reported. Orange values: p-value < 0.05; blue values: FC ≤ 0.83 or ≥1.2. (c) Detailed results for four proteins showing differential abundance in at least two of the assessed comparisons. The bar charts show the mean normalized area values for each group; error bars represent the standard error. Grey, uninfected controls; pink: patients with strongyloidiasis. All plots were generated using GraphPad Prism 8 (GraphPad Software LLC, MA, USA).

Figure 1.

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