Revisiting the Ancylostoma Caninum Secretome Provides New Information on Hookworm–Host Interactions

Abstract

Hookworm infection is a major tropical parasitic disease affecting almost 500 million people worldwide. These soil-transmitted helminths can survive for many years in the intestine of the host, where they feed on blood, causing iron deficiency anemia and other complications. These parasites release a variety of molecules known as excretory/secretory products (ESPs) that are involved in many different biological processes that govern parasite survival. Using a combination of separation techniques such as SDS-PAGE and OFFGEL electrophoresis, in combination with state-of-the-art mass spectrometry we have reanalyzed the dog hookworm, Ancylostoma caninum, ESPs (AcESP). We identified 315 proteins present in the AcESP, compared with just 105 identified in previous studies. The most highly represented family of proteins is the SCP/TAPs (110 of the 315 proteins), and the most abundant constituents of AcESP are homologues of the tissue inhibitors of metalloproteases (TIMP) family. Interestingly, we identified new homologs of well-known vaccine candidates and immunomodulatory proteins. This study provides novel information about the proteins secreted by A. caninum, and constitutes a comprehensive dataset to study the proteins involved in host-hookworm interactions.

Prospects of Using High-Throughput Proteomics to Underpin the Discovery of Animal Host–Nematode Interactions

“…However, it was not until 2020 that the first comprehensive proteomic analysis of a secretome of a human hookworm was reported [ 34 ]. In this study of Necator americanus [ 34 ], a total of 198 ES proteins were identified in the adult stage, 90% of which had homologs in the secretomes of three other strongylid nematodes (i.e., Ancylostoma caninum , Heligmosomoides polygyrus/bakeri and Nippostrongyus brasiliensis ) [ 31 , 35 , 36 ], confirming the value of these reference species for such studies. Of the 198 ES proteins identified/characterised for adult Necator americanus , ~ 30% of them belong to the group of SCP/TAPS proteins with one or two ‘SCP’ domains [ 34 ].…”

“…A particular example is the recent study of the dog hookworm Ancylostoma caninum . Using advanced LC-MS/MS combined with in-gel and off-gel electrophoresis, in 2017, Morante et al [ 31 ] identified nearly three times ( n = 315) the number of proteins reported previously ( n = 105) by Muvenna et al [ 32 ] in 2009. Facilitated by state-of-the-art MS and underpinned by genomic information, a re-analysis of the proteome only required a quarter of previously required amount of ES products (equating to 150 μg of protein versus 660 μg previously) [ 32 ].…”

Characterization of Trichuris muris secreted proteins and extracellular vesicles provides new insights into host–parasite communication

“…This family of proteins is abundantly expressed by parasitic nematodes and trematodes. For instance, they represent 35% of the ES products of the hookworm Ancylostoma caninum [67] and have been found in free-living and plant nematodes (reviewed by [68]). Their role is still unknown, although they have been suggested to play roles in fundamental biological processes such as larval penetration [69] and modulation of the immune response [70,71], in the transition from the free-living to the parasitic stage [72], and have even been explored as vaccine candidates against hookworm infections [73].…”

Characterisation of Trichuris muris secreted proteins and extracellular vesicles provides new insights into host-parasite communication

“…This family of proteins is abundantly expressed by parasitic nematodes and trematodes. For instance, they represent 35% of the ES products of the hookworm Ancylostoma caninum [67], and have been found in free-living and plant nematodes (reviewed by [68]). Their role is still unknown, although they have been suggested to play roles in fundamental biological processes such as larval penetration [69], modulation of the immune response [70, 71], in the transition from the free-living to the parasitic stage [72] and have even been explored as vaccine candidates against hookworm infections [73].…”