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Sotillo, J.

Publications and source records attributed to Sotillo, J..

12 recordsLinked to original sources

Fluke-borne viruses are a risk factor for diseases caused by carcinogenic trematodes

Three trematode parasites, Schistosoma haematobium, Opisthorchis viverrini, and Clonorchis sinensis are recognized group 1 carcinogens for their roles in squamous cell carcinoma of the urinary bladder and bile duct cancer (cholangiocarcinoma). We aimed to assess the presence of fluke viruses and their association with malignancy in fluke infections. We showed that all three carcinogenic trematodes harbored related viruses. Focusing on O. viverrini, we observed virus persistence at discrete life stages and viral tropism for the fluke tegument, and we provided molecular and serological evidence of parasitized hosts exposure to viral RNA and proteins. Serological analyses confirmed seroconversion of residents in endemic sites and revealed that antibody titers and avidity against fluke-borne viruses increase in individuals with hepatobiliary diseases. Random forest models discriminated efficiently between liver-fluke-infected participants without disease and those with periductal fibrosis or cholangiocarcinoma. Thus, we show that fluke-borne viruses are risk factors and diagnostic targets for fluke-associated cancer.

microbiology↗

Small extracellular vesicles but not microvesicles from Opisthorchis viverrini promote cell proliferation in human cholangiocytes.

Chronic infection with O. viverrini has been linked to the development of cholangiocarcinoma (CCA), which is a major public health burden in the Lower Mekong River Basin countries, including Thailand, Lao PDR, Vietnam and Cambodia. Despite its importance, the exact mechanisms by which O. viverrini promotes CCA are largely unknown. In this study, we characterized different extracellular vesicle populations released by O. viverrini (OvEVs) using proteomic and transcriptomic analyses and investigated their potential role in host-parasite interactions. While 120k OvEVs promoted cell proliferation in H69 cells at different concentrations, 15k OvEVs did not produce any effect compared to controls. The proteomic analysis of both populations showed differences in their composition that could contribute to this differential effect. Furthermore, the miRNAs present in 120k EVs were analysed and their potential interactions with human host genes was explored by computational target prediction. Different pathways involved in inflammation, immune response and apoptosis were identified as potentially targeted by the miRNAs present in this population of EVs. This is the first study showing specific roles for different EV populations in the pathogenesis of a parasitic helminth, and more importantly, an important advance towards deciphering the mechanisms used in establishment of opisthorchiasis and liver fluke infection-associated malignancy.

microbiology↗

Differential excretory/secretory proteome of the adult female and male stages of the human blood fluke, Schistosoma mansoni

Intricate molecular communication between the schistosome (flatworms) and its mammalian host, as well as between paired male and female schistosomes has shaped the secreted proteome of these flatworms. Whereas the schistosome egg is responsible for the disease manifestations of chronic schistosomiasis, the long lived, adult female and male stages also release mediators that facilitate their long-lived intra-vascular existence in a hostile niche where they are bathed in immune cells and effector molecules. However, despite their importance, no studies have focused on analysing the excretory/secretory products (ESPs) from adult schistosomes. Herein, ESPs from cultured Schistosoma mansoni male or female adult worms were identified, quantified, compared and contrasted using a label-free proteomic approach. Approximately 1,000 proteins were identified, from which almost 800 could be finally quantified. Considering the proteins uniquely identified and proteins with a significantly regulated expression pattern in male or female flukes, a total of 370 and 140 proteins were more abundantly secreted by males and females, respectively. Using functional analysis networks showing the gene ontology terms and KEGG pathways with the highest significance, we observed that male schistosomes secrete proteins related to carbohydrate metabolism, cytoskeletal organisation more abundantly than females, while female worms secreted more hydrolases and proteins involved in cellular homeostasis than males. This analysis doubles the number of previously reported ESPs from S. mansoni, contributing to a better understanding of the host-parasite dynamic interactions. Furthermore, these findings expand potential vaccine and diagnostic candidates for this neglected tropical disease pathogen, which will enable deeper understanding of the molecular communication critical to parasitism.

microbiology↗

Schistosoma haematobium extracellular vesicle proteins confer protection in a heterologous model of schistosomiasis

Helminth parasites release extracellular vesicles which interact with the surrounding host tissues, mediating host-parasite communication and other fundamental processes of parasitism. As such, vesicle proteins present attractive targets for the development of novel intervention strategies to control these parasites and the diseases they cause. Herein, we describe the first proteomic analysis by LC-MS/MS of two types of extracellular vesicles (exosome-like, 120k pellet vesicles and microvesicle-like, 15k pellet vesicles) from adult Schistosoma haematobium worms. A total of 57 and 330 proteins were identified in the 120k pellet vesicles and larger 15k pellet vesicles, respectively, and some of the most abundant molecules included homologues of known helminth vaccine and diagnostic candidates such as Sm-TSP2, Sm23, glutathione S-tranferase, saposins and aminopeptidases. Tetraspanins were highly represented in the analysis and found in both vesicle types. Vaccination of mice with recombinant versions of three of these tetraspanins induced protection in a heterologous challenge (S. mansoni) model of infection, resulting in significant reductions (averaged across two independent trials) in liver (47%, 38% and 41%) and intestinal (47%, 45% and 41%) egg burdens. These findings offer insight into the mechanisms by which anti-tetraspanin antibodies confer protection and highlight the potential that extracellular vesicle surface proteins offer as anti-helminth vaccines.

microbiology↗

Exosome-mediated crosstalk stimulated by liver fluke granulin promotes a microenvironment conducive to cholangiocarcinoma

Crosstalk between malignant and neighboring cells contributes to tumor growth. In East Asia, infection with fish-borne liver flukes is a major risk factor for cholangiocarcinoma (CCA). The parasite secretes a growth factor termed liver fluke granulin (Ov-GRN-1), a homologue of the human progranulin (huPGRN), which contributes significantly to biliary tract fibrosis and morbidity during infection. Here, exosome-mediated transfer of mRNAs from the human cholangiocyte cell line (H69) was investigated following exposure to Ov-GRN-1, to naive recipient H69 cells. To minimize the influence of endogenous huPGRN, the gene encoding huPGRN was inactivated using CRISPR/Cas9-based gene knock-out. Several huPGRN-depleted cell lines, termed {Delta}huPGRN-H69, were established. These lines exhibited >80% reductions in levels of huPGRN transcripts and protein, both in gene-edited cells and within exosomes released by these cells. Profiles of exosomal RNAs (exRNA) from {Delta}huPGRN-H69 for CCA-associated characteristics revealed a paucity of transcripts for estrogen- and Wnt-signaling pathways, peptidase inhibitors and tyrosine phosphatase related to cellular processes including oncogenic transformation. Several CCA-specific mRNAs including MAPK/AKT pathway members were induced by exposure to Ov-GRN-1. By comparison, estrogen, Wnt/PI3K and TGF signaling and other CCA pathway mRNAs were upregulated in wild type H69 exposed to Ov-GRN-1. Of these, CCA-associated exRNAs modified the CCA microenvironment in naive recipient cells co-cultured with exosomes from {Delta}huPGRN-H69 exposed to Ov-GRN-1, and induced translation of MAPK phosphorylation related-protein in naive recipient cells comparing with control recipient cells. Exosome-mediated crosstalk in response to liver fluke granulin promoted a CCA-specific program through MAPK pathway which, in turn, established a CCA-conducive disposition.

molecular biology↗

Novel cholinesterase paralogs of Schistosoma mansoni have perceived roles in cholinergic signaling, glucose scavenging and drug detoxification and are essential for parasite survival

Cholinesterase (ChE) function in schistosomes is essential for orchestration of parasite neurotransmission but has been poorly defined with respect to the molecules responsible. Interrogation of the S. mansoni genome has revealed the presence of three ChE domain-containing genes (Smche)s, which we have shown to encode two functional acetylcholinesterases (AChE)s (Smache1 - smp_154600 and Smache3 - smp_136690) and a butyrylcholinesterase (BChE) (Smbche1 - smp_125350). Antibodies to recombinant forms of each SmChE localized the proteins to the tegument and neuromusculature of adults and schistosomula and developmental expression profiling differed among the three molecules, suggestive of functions extending beyond traditional cholinergic signaling. For the first time in schistosomes, we identified ChE enzymatic activity in fluke excretory/secretory (ES) products and, using proteomic approaches, attributed this activity to the presence of SmAChE1 and SmBChE1. To address the hypothesis that tegumental AChE mediates exogenous glucose scavenging by the parasite, we show that RNAi-mediated knockdown of smache1 and smache3, but not smbche1, significantly reduces glucose uptake by schistosomes. Parasite survival in vitro and in vivo was significantly impaired by silencing of each smche, either individually or in combination, attesting to the essential roles of these molecules. Lastly, in the first characterization study of a BChE from helminths, evidence is provided that SmBChE1 may act as a bio-scavenger of AChE inhibitors as the addition of recombinant SmBChE1 to parasite cultures mitigated the effect of the anti-schistosome AChE inhibitor DDVP (DDVP), whereas smbche1-silenced parasites displayed increased sensitivity to DDVP.\n\nAuthor summaryCholinesterases - aceytlcholinesterases (AChE)s and butyrylcholinesterases (BChE)s - are multi-functional enzymes that play a pivotal role in the nervous system of parasites by regulating neurotransmission through acetylcholine hydrolysis. Herein, we provide a detailed characterization of schistosome cholinesterases using molecular, enzymatic and gene-silencing approaches and show evidence for these molecules having roles in glucose scavenging and drug detoxification, in addition to their neuronal function. Further, we demonstrate the importance of these proteins to parasite development and survival through gene knockdown experiments in laboratory animals, providing evidence for the use of these proteins in the development of novel intervention strategies against schistosomiasis.

molecular biology↗

Hemocyte subpopulation changes in Bithynia snails infected with Opisthorchis viverrini in Thailand.

The Bithynia snails of B. funiculata, B. siamensis siamensis and B. siamensis goniomphalos, are first intermediate hosts of Opisthorchis viverrini. The success of parasitic infection in snails is related to the host species and efficiency of their internal defense system. Parasitic infections in snails exhibited significant variations in the number of hemocytes in hemolymph. This study investigated hemocyte counts in Bithynia snails for various durations of O. viverrini infection. The three species/subspecies snails were infected with O. viverrini and hemocytes were counted at post-exposed periods of 2, 4, 6, 12, 24, 48, 96 h, and 1, 4 and 8 wk to evaluate the hemocyte response to the infection. Three major hemocyte morphotypes, namely, agranulocytes, semigranulocytes and granulocytes, were observed. After infection, the differential hemocyte morphotype counts in all species/subspecies significantly increased in granulocytes at 2 h (p < 0.05) and decreased in semigranulocytes and agranulocytes at 2 to 4 h (p < 0.05). The total hemocyte counts were significant increased at 2 h after exposure in B. s. siamensis and B. funiculata (p < 0.05). Additionally, the number of hemocytes was reduced after exposure at 4, 6 and 12 h in B. s. goniomphalos and at 12, 24 and 48 h in B. funiculata (p < 0.05). From 96 h to 8 wk, the number of hemocytes was reestablished in the hemolymph, indicating that defensive cells in the host species have different mechanisms for their susceptibility or resistance to parasitic infections. Further studies on molecular functions will be done.

immunology↗

In-depth proteomic characterization of Schistosoma haematobium: towards the development of new tools for elimination

BackgroundSchistosomiasis is a neglected disease affecting hundreds of millions worldwide. Of the three main species affecting humans, Schistosoma haematobium is the most common, and is the leading cause of urogenital schistosomiasis. S. haematobium infection can cause different urogential clinical complications, particularly in the bladder, and furthermore, this parasite has been strongly linked with squamous cell carcinoma. A comprehensive analysis of the molecular composition of its different proteomes will contribute to developing new tools against this devastating disease.\n\nMethods and FindingsBy combining a comprehensive protein fractionation approach consisting of OFFGEL electrophoresis with high-throughput mass spectrometry, we have performed the first in-depth characterisation of the different discrete proteomes of S. haematobium that are predicted to interact with human host tissues, including the secreted and tegumental proteomes of adult flukes and secreted and soluble egg proteomes. A total of 662, 239, 210 and 138 proteins were found in the adult tegument, adult secreted, soluble egg and secreted egg proteomes, respectively. In addition, we probed these distinct proteomes with urine to assess urinary antibody responses from naturally infected human subjects with different infection intensities, and identified adult fluke secreted and tegument extracts as being the best predictors of infection.\n\nConclusionWe provide a comprehensive dataset of proteins from the adult and egg stages of S. haematobium and highlight their utility as diagnostic markers of infection intensity for the development of novel tools to control this important neglected tropical disease.\n\nAuthor SummarySchistosomiasis is a neglected tropical disease affecting millions of people worldwide. Of the main three species affecting humans, Schistosoma haematobium is the most common, and is the leading cause of urogenital schistosomiasis. This parasite can cause a range of clinical complications associated with bladder pathogenesis, including squamous cell carcinoma as well as genital malignancy in women. Herein, we have performed the first comprehensive characterisation of the proteins implicated in host-parasite interactions (secreted and surface proteins from the adult flukes and secreted and soluble egg proteins) in order to advance our understanding of the parasites biology. Furthermore, we have characterised the different antibody responses in urine from infected human subjects from an endemic area presenting different infection intensities. The data obtained in this study can be used as a first step towards the development of novel tools for the control of urogenital schistosomiasis.

microbiology↗

Comprehensive analysis of human hookworm secreted proteins using a proteogenomic approach

The human hookworm Necator americanus infects more than 400 million people worldwide, contributing substantially to the poverty in these regions. Adult stage N. americanus live in the small intestine of the human host where they inject excretory/secretory (ES) products into the mucosa. ES products have been characterized at the proteome level for a number of animal hookworm species, but until now, the difficulty in obtaining sufficient live N. americanus has been an obstacle in characterizing the secretome of this important human pathogen. Herein we describe the ES proteome of N. americanus and utilize this information to conduct the first proteogenomic analysis of a parasitic helminth, significantly improving the available genome and thereby generating a robust description of the parasite secretome. The genome annotation resulted in a a revised prediction of 3,425 fewer genes than initially reported, accompanied by a significant increase in the number of exons and introns, total gene length and the percentage of the genome covered by genes. Almost 200 ES proteins were identified by LC-MS/MS with SCP/TAPS proteins, hypothetical proteins and proteases among the most abundant families. These proteins were compared to commonly used model species of human parasitic infections, including Ancylostoma caninum, Nippostrongylus brasiliensis and Heligmosomoides polygyrus. Our findings provide valuable information on important families of proteins with both known and unknown functions that could be instrumental in host-parasite interactions, including protein families that might be key for parasite survival in the onslaught of robust immune responses, as well as vaccine and drug targets.

microbiology↗

Programmed mutation of liver fluke granulin using CRISPR/Cas9 attenuates virulence of infection-induced hepatobiliary morbidity

Infections with several flatworm parasites represent group 1 biological carcinogens, i.e. definite causes of cancer. Infection with the food-borne liver fluke Opisthorchis viverrini causes cholangiocarcinoma (CCA). Whereas the causative agent for most cancers, including CCA in the West, remains obscure, the principal risk factor for CCA in Thailand is opisthorchiasis. We exploited this established link to explore the role of the secreted parasite growth factor termed liver fluke granulin (Ov-GRN-1) in pre-malignant lesions of the biliary tract. We targeted the Ov-grn-1 gene for programmed knockout and investigated gene-edited parasites in vitro and in experimentally infected hamsters. Both adult and juvenile stages of the liver fluke were transfected with a plasmid encoding a guide RNA sequence specific for exon 1 of Ov-grn-1 and the Cas9 nuclease. Deep sequencing of amplicon libraries from genomic DNA from gene-edited parasites exhibited programmed, Cas9-catalyzed mutations within the Ov-grn-1 locus, and tandem analyses by RT-PCR and western blot revealed rapid depletion of Ov-grn-1 transcripts and protein. Newly excysted juvenile flukes that had undergone editing of Ov-grn-1 colonized the biliary tract, grew and developed over a period of 60 days, were active and motile, and induced a clinically relevant pathophysiological tissue phenotype of attenuated biliary hyperplasia and fibrosis in comparison to infection with wild type flukes. This is the first report of gene knock-out using CRISPR/Cas9 in a parasitic flatworm, demonstrating the activity and utility of the process for functional genomics in these pathogens. The striking clinical phenotype highlights the role in virulence that liver fluke growth factors play in biliary tract morbidity during chronic opisthorchiasis.

molecular biology↗

Revisiting The Ancylostoma caninum Secretome Provides New Information On Hookworm-Host Interactions

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 anaemia and other complications. To avoid the hosts immune response the parasite releases excretory/secretory products (ESPs), a complex mixture of glycans, lipids and proteins that represent the major host-parasite interface. Using a combination of separation techniques such as SDS-PAGE and OFFGEL electrophoresis, in combination with state-of-the-art mass spectrometry we have reanalysed the dog hookworm, Ancylostoma caninum, ESPs (AcES). We identified 315 proteins present in the AcES, compared with just 105 identified in previous studies. The most highly represented family of proteins is the SCP/TAPs (90 of the 315 proteins), and the most abundant constituents of AcES are homologues of the tissue inhibitors of metalloproteases (TIMP) family. We identified putative vaccine candidates and proteins that could have immunomodulatory effects for treating inflammatory diseases. This study provides novel information about the proteins involved in host-hookworm interactions, and constitutes a comprehensive dataset for the development of vaccines and the discovery of new immunoregulatory biologics.

microbiology↗

Characterisation Of Trichuris muris Secreted Proteins And Extracellular Vesicles Provides New Insights Into Host-Parasite Communication

Whipworms are parasitic nematodes that live in the gut of more than 500 million people worldwide. Due to the difficulty in obtaining parasite material, the mouse whipworm Trichuris muris has been extensively used as a model to study human whipworm infections. These nematodes secrete a multitude of compounds that interact with host tissues where they orchestrate a parasitic existence. Herein we provide the first comprehensive characterisation of the excretory/secretory products of T. muris. We identify 148 proteins secreted by T. muris and show for the first time that the mouse whipworm secretes exosome-like extracellular vesicles (EVs) that can interact with host cells. We use an Optiprep(R) gradient to purify the EVs, highlighting the suitability of this method for purifying EVs secreted by a parasitic nematode. We also characterise the proteomic and genomic content of the EVs, identifying >350 proteins, 56 miRNAs (22 novel) and 475 full-length mRNA transcripts mapping to T. muris gene models. Many of the miRNAs putatively mapped to mouse genes involved in regulation of inflammation, implying a role in parasite-driven immunomodulation. In addition, for the first time to our knowledge, we use colonic organoids to demonstrate the internalisation of parasite EVs by host cells. Understanding how parasites interact with their host is crucial to develop new control measures. This first characterisation of the proteins and EVs secreted by T. muris provides important information on whipworm-host communication and forms the basis for future studies.

microbiology↗