Screening trematodes for novel intervention targets: a proteomic and immunological comparison of Schistosoma haematobium, Schistosoma bovis and Echinostoma caproni

Abstract

SUMMARYWith the current paucity of vaccine targets for parasitic diseases, particularly those in childhood, the aim of this study was to compare protein expression and immune cross-reactivity between the trematodes Schistosoma haematobium, S. bovis and Echinostoma caproni in the hope of identifying novel intervention targets. Native adult parasite proteins were separated by 2-dimensional gel electrophoresis and identified through electrospray ionisation tandem mass spectrometry to produce a reference gel. Proteins from differential gel electrophoresis analyses of the three parasite proteomes were compared and screened against sera from hamsters infected with S. haematobium and E. caproni following 2-dimensional Western blotting. Differential protein expression between the three species was observed with circa 5% of proteins from S. haematobium showing expression up-regulation compared to the other two species. There was 91% similarity between the proteomes of the two Schistosoma species and 81% and 78·6% similarity between S. haematobium and S. bovis versus E. caproni, respectively. Although there were some common cross-species antigens, species-species targets were revealed which, despite evolutionary homology, could be due to phenotypic plasticity arising from different host-parasite relationships. Nevertheless, this approach helps to identify novel intervention targets which could be used as broad-spectrum candidates for future use in human and veterinary vaccines.

The helminth parasite proteome at the host–parasite interface – Informing diagnosis and control

“…Future aspiration include development of diagnostics and control measures (such as vaccination) that can be used against multiple parasite species/groups and comparative proteomic studies between different species (such as those described in Higon et al (2011), Boukli et al (2011) will yield valuable information. With increasing clarity and information provided by the sequence data emerging from the Sanger helminth Genomes Initiative (Wellcome Trust Sanger Institute, 2015) sequencing genomes of human and veterinary helminths there is scope for interventions targeted at common molecules/pathways amongst the different helminths.…”

“…Cross-reactivity between proteins from different parasites can be a problem. Sera from infected hamsters showed cross-reactivity between S. haematobium and S. bovis in a study by Higon et al (2011). The reported cross-reactivity was limited, but still present between S. haematobium and E. caproni.…”

Screening Diagnostic Candidates for Schistosomiasis from Tegument Proteins of Adult Schistosoma japonicum Using an Immunoproteomic Approach

“…haematobium , S . bovis , and Echinostoma caproni has been studied [ 24 ], and common cross-species antigens and species-specific targets have been identified. Excretory and secretory antigens of S .…”

Immunoproteomic analysis of Schistosoma japonicum schistosomulum proteins recognized by immunoglobulin G in the sera of susceptible and non-susceptible hosts

“…During the past few years, immunoproteomics has become an increasingly popular method that has been used widely for identifying various types of immunoreactive proteins in bacteria and parasites [15][16][17][18][19][20][21]. Adult Schistosoma haematobium soluble worm antigens were recognized by pooled serum samples from infected Zimbabweans using immunoproteomics [15].…”

“…Four immunoreactive antigens have been identified successfully and recombinant leucine aminopeptidase and fructose bisphosphate aldolase can be used for the diagnosis of S. japonica. The immune cross-reactivity between the trematodes S. haematobium, Schistosoma bovis, and Echinostoma caproni has been studied in recent years, and some common cross-species antigens and species-species targets have been identified [17]. All these findings will help us to develop novel vaccine candidates and/or serological diagnostic markers.…”