Echinococcus metacestode: in search of viability markers

Immunomodulatory effects of hydatid antigens on mesenchymal stem cells: gene expression alterations and functional consequences

Background

Cystic echinococcosis, caused by the larval stage of Echinococcus granulosus, remains a global health challenge. Mesenchymal stem cells (MSCs) are renowned for their regenerative and immunomodulatory properties. Given the parasite's mode of establishment, we postulate that MSCs likely play a pivotal role in the interaction between the parasite and the host. This study aims to explore the response of MSCs to antigens derived from Echinococcus granulosus, the etiological agent of hydatid disease, with the hypothesis that exposure to these antigens may alter MSC function and impact the host's immune response to the parasite.

Methods

MSCs were isolated from mouse bone marrow and co-cultured with ESPs, HCF, or pLL antigens. We conducted high-throughput sequencing to examine changes in the MSCs' mRNA expression profile. Additionally, cell cycle, migration, and secretory functions were assessed using various assays, including CCK8, flow cytometry, real-time PCR, Western blot, and ELISA.

Results

Our analysis revealed that hydatid antigens significantly modulate the mRNA expression of genes related to cytokine and chemokine activity, impacting MSC proliferation, migration, and cytokine secretion. Specifically, there was a downregulation of chemokines (MCP-1, CXCL1) and pro-inflammatory cytokines (IL-6, NOS2/NO), alongside an upregulation of anti-inflammatory mediators (COX2/PGE2). Furthermore, all antigens reduced MSC migration, and significant alterations in cellular metabolism-related pathways were observed.

Conclusion

Hydatid disease antigens induce a distinct immunomodulatory response in MSCs, characterized by a shift towards an anti-inflammatory phenotype and reduced cell migration. These changes may contribute to the parasite's ability to evade host defenses and persist within the host, highlighting the complex interplay between MSCs and hydatid disease antigens. This study provides valuable insights into the pathophysiology of hydatid disease and may inform the development of novel therapeutic strategies.

Exploration of altered miRNA expression and function in MSC-derived extracellular vesicles in response to hydatid antigen stimulation

Background

Hydatid disease is caused by Echinococcus parasites and can affect various tissues and organs in the body. The disease is characterized by the presence of hydatid cysts, which contain specific antigens that interact with the host's immune system. Mesenchymal stem cells (MSCs) are pluripotent stem cells that can regulate immunity through the secretion of extracellular vesicles (EVs) containing microRNAs (miRNAs).

Methods

In this study, hydatid antigens were isolated from sheep livers and mice peritoneal cavities. MSCs derived from mouse bone marrow were treated with different hydatid antigens, and EVs were isolated and characterized from the conditioned medium of MSCs. Small RNA library construction, miRNA target prediction, and differential expression analysis were conducted to identify differentially expressed miRNAs. Functional enrichment and network construction were performed to explore the biological functions of the target genes. Real-time PCR and Western blotting were used for miRNA and gene expression verification, while ELISA assays quantified TNF, IL-1, IL-6, IL-4, and IL-10 levels in cell supernatants.

Results

The study successfully isolated hydatid antigens and characterized MSC-derived EVs, demonstrating the impact of antigen concentration on MSC viability. Key differentially expressed miRNAs, such as miR-146a and miR-9-5p, were identified, with functional analyses revealing significant pathways like Endocytosis and MAPK signaling associated with these miRNAs' target genes. The miRNA-HUB gene regulatory network identified crucial miRNAs and HUB genes, such as Traf1 and Tnf, indicating roles in immune modulation and osteogenic differentiation. Protein-protein interaction (PPI) network analysis highlighted central HUB genes like Akt1 and Bcl2. ALP activity assays confirmed the influence of antigens on osteogenic differentiation, with reduced ALP activity observed. Expression analysis validated altered miRNA and chemokine expression post-antigen stimulation, with ELISA analysis showing a significant reduction in CXCL1 expression in response to antigen exposure.

Conclusion

This study provides insights into the role of MSC-derived EVs in regulating parasite immunity. The findings suggest that hydatid antigens can modulate the expression of miRNAs in MSC-derived EVs, leading to changes in chemokine expression and osteogenic capacity. These findings contribute to a better understanding of the immunomodulatory mechanisms involved in hydatid disease and provide potential therapeutic targets for the development of new treatment strategies.

Circulating Small RNA Profiling of Patients with Alveolar and Cystic Echinococcosis

Alveolar (AE) and cystic (CE) echinococcosis are two parasitic diseases caused by the tapeworms Echinococcus multilocularis and E. granulosus sensu lato (s. l.), respectively. Currently, AE and CE are mainly diagnosed by means of imaging techniques, serology, and clinical and epidemiological data. However, no viability markers that indicate parasite state during infection are available. Extracellular small RNAs (sRNAs) are short non-coding RNAs that can be secreted by cells through association with extracellular vesicles, proteins, or lipoproteins. Circulating sRNAs can show altered expression in pathological states; hence, they are intensively studied as biomarkers for several diseases. Here, we profiled the sRNA transcriptomes of AE and CE patients to identify novel biomarkers to aid in medical decisions when current diagnostic procedures are inconclusive. For this, endogenous and parasitic sRNAs were analyzed by sRNA sequencing in serum from disease negative, positive, and treated patients and patients harboring a non-parasitic lesion. Consequently, 20 differentially expressed sRNAs associated with AE, CE, and/or non-parasitic lesion were identified. Our results represent an in-depth characterization of the effect E. multilocularis and E. granulosus s. l. exert on the extracellular sRNA landscape in human infections and provide a set of novel candidate biomarkers for both AE and CE detection.

Risk factors for post-endoscopic retrograde cholangiopancreatography cholangitis in patients with hepatic alveolar echinococcosis-an observational study

BACKGROUND

Hepatic alveolar echinococcosis (HAE) is considered to be one of the most deadly chronic parasitic diseases in the world. We have shown that the incidence of cholangitis in patients who underwent endoscopic retrograde cholangiopancreatography (ERCP) was increased significantly. On this finding, we carried out, a preliminary study on the risk factors for cholangitis after ERCP.

AIMS

To retrospectively detect the risk factors for post-ERCP cholangitis in patients with biliary tract affected by HAE.

METHODS

The study included data from 51 cases of AE who had undergone therapeutic ERCP between January 2015 and December 2019. Demographic and treatment data were extracted from the medical records, and the association between potential risk factors and the development of post-ERCP cholangitis was evaluated using a collected database.

RESULTS

There were five cases of mild cholangitis after ERCP (Tokyo criteria), and no moderate or severe cholangitis occurred. The incidence rate of cholangitis after ERCP was 9.8%. Univariate analysis showed hilar bile duct stenosis (p = .016), endoscopic retrograde biliary drainage (p = .007), a stent diameter ≥8.5 Fr (p = .000) and single stent implantation (p = .010) were risk factors for post -ERCP cholangitis. All cases of cholangitis improved under conservative treatment.

CONCLUSION

Patients with hilar bile duct compression or endoscopic retrograde biliary drainage appeared to be more likely to develop post-ERCP cholangitis. The number and diameter of biliary stents may influence post-ERCP cholangitis. Sample size and clinical heterogeneity are two insurmountable difficulties, and a larger sample size needs to be collected to verify the risk factors for screening. KEY MESSAGESMany studies reported the post-ERCP complications in patients with hepatic alveolar echinococcosis and found that the incidence of post-ERCP cholangitis was significantly high. Therefore, we conducted a preliminary study on the risk factors of postoperative cholangitis in patients who underwent ERCP.The incidence rate of cholangitis after ERCP was 9.8%. We found that hilar bile duct stenosis, and endoscopic retrograde biliary drainage, were risk factors for cholangitis, and stent diameter and the number of stent implantation may influence the incidence rate of cholangitis after ERCP.Sample size and clinical heterogeneity are two insurmountable difficulties, and a larger sample size needs to be collected to verify the risk factors of screening.

One-tube nested MGB Probe Real-time PCR assay for detection of Echinococcus multilocularis infection in plasma cell free DNA

INTRODUCTION

The main objective of this study was to develop a One-tube nested MGB probe real-time PCR Assay for detecting Echinococcus multilocularis infection in human plasma cell free DNA (cfDNA).

METHODS

cfDNA was extracted from 10 E.m.-infected patients using a NucleoSnap DNA Plasma Kit and characterized by genomic sequencing. We designed nested PCR primers and MGB probe for Echinococcus multilocularis detection. The specificity, sensitivity and reproducibility of this assay were analyzed, and its validity was confirmed in 13 early stage clinical samples.

RESULTS

Several Echinococcus multilocularis-specific sequences were detected in the cfDNA of E.m.-infected patients, and CBLO020001206.1 was selected as the candidate sequence. We designed the primers and probe for the one tube nested real-time PCR. No cross-reactions with E.g. were observed. The detection limit was as low as 1 copy for Echinococcus multilocularis. The coefficients of variation were lower than 5% in intra- and inter-assays. 11 out of 13 patients were positive with nested MGB Probe PCR Assay and 3 patients were positive without outer primer in early stage Alveolar Echinococcosis pateints.

CONCLUSION

The one-tube nested MGB probe real-time PCR assay is a simple, rapid, and cost-effective method for detection of Echinococcus multilocularis infection in patients' Plasma DNA.

Follow-up PET/CT of alveolar echinococcosis: Comparison of metabolic activity and immunodiagnostic testing

Purpose

To investigate the potential role of follow-up ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in therapy control of inoperable patients with alveolar echinococcosis.

Materials and methods

In this single-center retrospective cohort study, 48 PET/CT of 16 patients with confirmed alveolar echinococcosis were analysed. FDG-uptake of the most active echinococcosis manifestation was measured (i.e., maximum standardized uptake value (SUVmax) and in relation to background activity in normal liver tissue (SUVratio)) and compared to immunodiagnostic testing. For clinical patient follow-up, patient demographics, laboratory data, including E. granulosus hydatid fluid (EgHF) antibody units (AU) as well as clinical and treatment information were assessed for all patients at the time of PET/CT, and at the last recorded clinical visit.

Results

Metabolic activity of PET/CT measured in the echinococcosis manifestation was significantly correlated with EgHF AU (p < 0.001). The differences in metabolic activity of echinococcosis manifestations between two consecutive PET/CT examinations of the same patient and differences in EgHF AU in the respective time intervals displayed a significant positive correlation (p = 0.01). A trend for a more rapid decline in SUVratio liver over time was found in patients who stopped benzimidazole therapy versus patients who did not stop therapy (p = 0.059).

Conclusion

In inoperable patients with alveolar echinococcosis, the course of metabolic activity in follow-up PET/CT is associated to the course EgHF antibody levels. Both parameters may potentially be used to evaluate the course of the disease and potentially predict the duration of benzimidazole therapy.

Retrospective Determination of the Prevelense of Anti-Echinococcus granulosus Antibodies in Cystic Echinococcosis Pre-diagnosed Patients at Erciyes University Faculty of Medicine

OBJECTIVE

Cystic echinococcosis (CE) is a parasitic disease that has been known for years in helminth diseases and it is important as human and animal health problem in many parts of the world and in our country due to economic losses. In this study, it was aimed to retrospectively evaluate the distribution of anti-E. granulosus-IgG antibodies in patients with pre-diagnosis of CE that referred to parasitology laboratory between January 2013-December 2018.

METHODS

Commercial kit was used for indirect hemaglutination (IHA), indirect fluorescent antibody test (IFAT) and Western blot (WB) methods using sera from patient samples was applied according to the kit proposal. In addition, patient materials for CAM, CSF and blood for which polymerase chain reaction (PCR)/QPCR tests were requested were examined.

RESULTS

Sera of the patients who were tested with at least one of the IHA, IFAT and WB methods or a combination of these methods, and 443 cases out of 2.283 cases were found to be E. granulosus seropositive. It was determined that 369 (62.03%) of 443 positive patients were female and 330 (37.97%) were male patients. Among these patients, 87 patients whose IFAT and/or IHA tests were negative were found to have positive results with the WB method. IFAT or IHA test results of 13 patients with negative WB tests were found to be positive. Four patients were identified with both tests positive but WB test results negative. In addition, 36 of 72 patients who underwent PCR/QPCR tests were found to be positive.

CONCLUSION

As a result of a six-year retrospective screening, 22% of the cases were found to be positive, and it was concluded that the prevalence of CE is high and the use of a single test may be insufficient in the diagnosis of CE, therefore, test combinations will increase the sensitivity and reliability in reaching the correct diagnosis.

Structural changes and expression of hepatic fibrosis-related proteins in coculture of Echinococcus multilocularis protoscoleces and human hepatic stellate cells

Background

Echinococcus multilocularis is the causative agent of human hepatic alveolar echinococcosis (AE). AE can cause damage to several organs, primarily the liver, and have severe outcomes, such as hepatic failure and encephalopathy. The main purpose of this study was to explore the interactions between hepatic stellate cells (HSCs) and E. multilocularis protoscoleces (PSCs). The results of this study provide an experimental basis for further examination of the pathogenesis of hepatic fibrosis due to AE infection.

Methods

We investigated the role of Echinococcus multilocularis (Echinococcus genus) PSCs in hepatic fibrosis by examining structural changes and measuring hepatic fibrosis-related protein levels in cocultures of PSCs and human HSCs. Structural changes were detected by transmission electron microscopy (TEM), and levels of the hepatic fibrosis-related proteins collagen I (Col-I), alpha-smooth muscle actin (α-SMA) and osteopontin (OPN) were measured by western blotting and enzyme-linked immunosorbent assay (ELISA).

Results

Under coculture (1) both PSCs and HSCs exhibited morphological changes, as observed by TEM; (2) Col-I, α-SMA, and OPN expression levels, which were determined by western blotting and ELISA, significantly increased after 3 days of incubation.

Conclusions

The results of this study provide insights into the molecular mechanisms of AE-induced hepatic fibrosis.

Graphical abstract

Recent advances in ultrasound in the diagnosis and evaluation of the activity of hepatic alveolar echinococcosis

Echinococcosis is a worldwide neglected zoonotic disease. Alveolar echinococcosis (AE) poses a more serious threat to life and health than cystic echinococcosis, and has been one of the world's most lethal chronic parasitosis. Assessment of metacestode activity status is essential for individual treatment strategy design for a given AE patient, and fluorodeoxyglucose positron-emission tomography (FDG-PET) has been the gold standard. In this study, we reviewed previous evidence on AE activity assessment using contrast-enhanced ultrasound (CEUS), and its comparison with FDG-PET. The results showed good consistency between them, indicating CEUS as a suitable substitute for FDG-PET. With its advantage as being readily portable, widely available, and not costly, CEUS is more suitable for use in the developing countries and rural areas.

Hepatic Alveolar Echinococcosis

Hepatic alveolar echinococcosis (HAE) is a rare but severe zoonosis caused by the pseudotumoral intrahepatic development of the larval stage of the tapeworm Echinococcus multilocularis. HAE is present only in the Northern Hemisphere, predominantly in China. Currently, there is a significant resurgence of cases in historically endemic areas associated with emergence of HAE in countries not previously concerned. Today, in European countries, HAE is often discovered by chance; however, clinicians should be made aware of opportunistic infections that progressively emerged recently as a result of therapeutic or pathological immunosuppression. Ultrasonography is the key first-line diagnostic procedure, with specific serology providing confirmation in 95% of the cases. Albendazole, only parasitostatic, is the mainstay for treatment. Surgical resection, if feasible, is the gold standard for treatment, and more patients are currently eligible for this option because of an earlier diagnosis. The prognosis has considerably improved but remains poor in countries where access to care is less favorable.

Development of Optical Biosensor Using Protein A-Conjugated Chitosan-Gold Nanoparticles for Diagnosis of Cystic Echinococcosis

Human echinococcosis is a serious parasitic diseasethat still affects millions of people in many parts of the world. Since it can offer a critical threat to people's health, it is important to discover a rapid, convenient, and economical method for detection. Herein, we propose a novel point of care assay, namely, an enhanced immuno-dot-blot assay for diagnosis of cystic echinococcosis (hydatidosis). This method is based on the formation of a sandwich complex between a goldnanoprobe (chitosan-gold nanoparticleprotein A) and hydatid cyst antigen (Ag B), which holds anti-Ag B antibodies. Briefly, protein A was conjugated to chitosan-gold nanoparticles via glutaraldehyde chemistry. Then, Ag B was immobilized on the surface of a nitrocellulose membrane, which was followed by the addition of the sera sample and gold nanoprobes. The positive signals were easily detectable by naked eye. The signal intensity of this biosensor was proportional to the concentration of active anti-Echinococcus granulosus antibodies on the surface of the nanoparticles, titer of antibodies in the sera samples, and concentration of Ag B coated on the nitrocellulose membrane. The minimum concentration to use the protein A for conjugation to detect titer of anti-Echinococcus IgGand the concentration of Ag B coated in nitrocellulose membrane were 0.5 and 0.3 mg/mL, respectively. This enhanced immuno-dot-blot assay offers a simple diagnostic technique withoutthe need for expensive equipment for diagnosis of echinococcosis.

microRNA-125b-5p is a promising novel plasma biomarker for alveolar echinococcosis in patients from the southern province of Qinghai

Background

Alveolar echinococcosis (AE) is caused by parasitic infection by Echinococcus multilocularis. Its diagnosis is usually based on clinical symptoms, ultrasound, and other imaging methods. MicroRNAs (miRNAs) play important roles in disease processes and can exist in a highly stable cell-free form in body fluids. It is important to identify specific, sensitive diagnostic markers for early diagnosis and evaluation of AE. In this study, we examined hsa-miR-125b-5p as a potential plasma biomarker of E. multilocularis infection.

Methods

Plasma samples from patients with AE and healthy individuals were screened for the presence of five miRNAs using miRNA chips. We used quantitative polymerase chain reaction to measure miRNA expression levels in plasma and liver tissue samples from patients with AE.

Results

hsa-miR-125b-5p was stably upregulated in the plasma and liver tissue samples from patients with AE.

Conclusions

The results suggest that hsa-miR-125b-5p may be a promising biomarker for early, non-invasive diagnosis of AE.

Extracellular non-coding RNA signatures of the metacestode stage of Echinococcus multilocularis

Extracellular RNAs (ex-RNAs) are secreted by cells through different means that may involve association with proteins, lipoproteins or extracellular vesicles (EV). In the context of parasitism, ex-RNAs represent new and exciting communication intermediaries with promising potential as novel biomarkers. In the last years, it was shown that helminth parasites secrete ex-RNAs, however, most work mainly focused on RNA secretion mediated by EV. Ex-RNA study is of special interest in those helminth infections that still lack biomarkers for early and/or follow-up diagnosis, such as echinococcosis, a neglected zoonotic disease caused by cestodes of the genus Echinococcus. In this work, we have characterised the ex-RNA profile secreted by in vitro grown metacestodes of Echinococcus multilocularis, the casuative agent of alveolar echinococcosis.

We have used high throughput RNA-sequencing together with RT-qPCR to characterise the ex-RNA profile secreted towards the extra- and intra-parasite milieus in EV-enriched and EV-depleted fractions. We show that a polarized secretion of small RNAs takes place, with microRNAs mainly secreted to the extra-parasite milieu and rRNA- and tRNA-derived sequences mostly secreted to the intra-parasite milieu. In addition, we show by nanoparticle tracking analyses that viable metacestodes secrete EV mainly into the metacestode inner vesicular fluid (MVF); however, the number of nanoparticles in culture medium and MVF increases > 10-fold when metacestodes show signs of tegument impairment. Interestingly, we confirm the presence of host miRNAs in the intra-parasite milieu, implying their internalization and transport through the tegument towards the MVF. Finally, our assessment of the detection of Echinococcus miRNAs in patient samples by RT-qPCR yielded negative results suggesting the tested miRNAs may not be good biomarkers for this disease.

A comprehensive study of the secretion mechanisms throughout the life cycle of these parasites will help to understand parasite interaction with the host and also, improve current diagnostic tools.

Extracellular RNAs (ex-RNAs) are secreted by cells through association with proteins or extracellular vesicles (EV). In the context of parasitism, ex-RNAs represent novel communication intermediaries with promising potential as biomarkers. In order to better understand the role ex-RNAs may play in the context of the zoonotic disease echinococcosis, we have characterised the RNA profile secreted by the larval stage (metacestode) of Echinococcus multilocularis.

By analysing the products secreted towards the extra- and intra-parasite milieus, we demonstrate that the metacestode displays a polarized secretion of different classes of small non-coding RNAs (sRNAs). In addition, we show that EV secretion occurs mainly towards the inner fluid of the metacestodes. Interestingly, we confirm the presence of host sRNAs in the intra-parasite milieu, implying their internalization and transport through the tegument. Finally, the detection of Echinococcus miRNAs in patient samples yielded negative results suggesting the tested miRNAs may not be good biomarkers for this disease.

In summary, our results provide a detailed description of the ex-RNA landscape of the E. multilocularis metacestode together with information on the distribution of the detected RNA classes in different extracellular compartments. This information is of importance to better understand host-parasite interaction and also, to improve current diagnostic tools.

Diagnostic urinary cfDNA detected in human cystic echinococcosis

Cystic echinococcosis (CE) is a major neglected tropical zoonotic disease caused by the tissue-dwelling larval stage of the cestode parasite Echinococcus granulosus. For individuals suspected of CE, the diagnostic standard is imaging using ultrasonography, X rays, or computed tomography. These resource-demanding and expensive procedures are rarely available in endemic rural areas where CE is most prevalent. There is a critical need for a new approach to identify CE patients so that they can be managed early in the course of their infection. This study reports on the results of a diagnostic approach that identifies E. granulosus-derived cell-free DNA (cfDNA) in the urine of CE patients. Utilizing PCR to amplify a fragment of a major tandem repeat element found in E. granulosus nuclear DNA, urine samples from all seven imaging-confirmed CE patients who harbored active liver cysts were positive. In addition, the urine samples from 2/4 patients who presented with non-viable/calcified liver cysts were also PCR positive for the repeat fragment. To our knowledge, this is the first report of using parasite cfDNA from urine to diagnose CE. This approach provides an easy to implement and cost-effective method to survey for the prevalence of E. granulosus in humans populations.

International consensus on terminology to be used in the field of echinococcoses

Echinococcoses require the involvement of specialists from nearly all disciplines; standardization of the terminology used in the field is thus crucial. To harmonize echinococcosis terminology on sound scientific and linguistic grounds, the World Association of Echinococcosis launched a Formal Consensus process. Under the coordination of a Steering and Writing Group (SWG), a Consultation and Rating Group (CRG) had the main missions of (1) providing input on the list of terms drafted by the SWG, taking into account the available literature and the participants’ experience; and (2) providing independent rating on all debated terms submitted to vote. The mission of the Reading and Review Group (RRG) was to give an opinion about the recommendation paper in terms of readability, acceptability and applicability. The main achievements of this process were: (1) an update of the current nomenclature of Echinococcus spp.; (2) an agreement on three names of diseases due to Echinococcus spp.: Cystic Echinococcosis (CE), Alveolar Echinococcosis (AE) and Neotropical Echinococcosis (NE), and the exclusion of all other names; (3) an agreement on the restricted use of the adjective “hydatid” to refer to the cyst and fluid due to E. granulosus sensu lato; and (4) an agreement on a standardized description of the surgical operations for CE, according to the “Approach, cyst Opening, Resection, and Completeness” (AORC) framework. In addition, 95 “approved” and 60 “rejected” terms were listed. The recommendations provided in this paper will be applicable to scientific publications in English and communication with professionals. They will be used for translation into other languages spoken in endemic countries.

Comprehensive characterization of plasma cell-free Echinococcus spp. DNA in echinococcosis patients using ultra-high-throughput sequencing

Background

Echinococcosis is a life-threatening parasitic disease caused by Echinococcus spp. tapeworms with over one million people affected globally at any time. The Echinococcus spp. tapeworms in the human body release DNA to the circulatory system, which can be a biomarker for echinococcosis. Cell-free DNA (cfDNA) is widely used in medical research and has been applied in various clinical settings. As for echinococcosis, several PCR-based tests had been trialed to detect cell-free Echinococcus spp. DNA in plasma or serum, but the sensitivity was about 20% to 25%. Low sensitivity of PCR-based methods might be related to our limited understanding of the features of cell-free Echinococcus spp. DNA in plasma, including its concentration, fragment pattern and release source. In this study, we applied ultra-high-throughput sequencing to comprehensively investigate the characteristics of cell-free Echinococcus spp. DNA in plasma of echinococcosis patients.

Methodology/Principal findings

We collected plasma samples from 23 echinococcosis patients. Total plasma cfDNA was extracted and sequenced with a high-throughput sequencing platform. An average of 282 million read pairs were obtained for each plasma sample. Sequencing data were analyzed with bioinformatics workflow combined with Echinococcus spp. sequence database. After identification of cell-free Echinococcus spp. reads, we found that the cell-free Echinococcus spp. reads accounted for 1.8e-5 to 4.0e-9 of the total clean reads. Comparing fragment length distribution of cfDNA between Echinococcus spp. and humans showed that cell-free Echinococcus spp. DNA of cystic echinococcosis (CE) had a broad length range, while that of alveolar echinococcosis (AE) had an obvious peak at about 135 bp. We found that most of the cell-free Echinococcus spp. DNA reads were from the nuclear genome with an even distribution, which might indicate a random release pattern of cell-free Echinococcus spp. DNA.

Conclusions/Significance

With ultra-high-throughput sequencing technology, we analyzed the concentration, fragment length, release source, and other characteristics of cell-free Echinococcus spp. DNA in the plasma of echinococcosis patients. A better understanding of the characteristics of cell-free Echinococcus spp. DNA in plasma may facilitate their future application as a biomarker for diagnosis.

Echinococcosis is one of the most neglected tropical diseases caused by the metacestodes of Echinococcus spp. tapeworms, which affect both humans and livestock. Plasma cell-free DNA (cfDNA) consists of nucleic acid fragments found extracellularly and may contain DNA released from the parasites. Research shows that a variety of parasites can be detected from plasma cfDNA. Cell-free Echinococcus spp. DNA in plasma or serum had been tested with PCR-based methods, but these PCR methods had low sensitivity ranged from 20% to 25%. Low sensitivity may be due to our limited understanding of cell-free Echinococcus spp. DNA in plasma. Here, we take advantage of high-throughput sequencing to get a comprehensive characterization of cell-free Echinococcus spp. DNA. Our results showed that with high-throughput sequencing we could detect cell-free Echinococcus spp. DNA in all samples, though at a very low level. Based on the sequencing data, we found that cell-free Echinococcus spp. DNA in plasma had a different fragment length distribution to cell-free human DNA, and fragment length distribution of cell-free Echinococcus spp. DNA is also different between cystic echinococcosis (CE) and alveolar echinococcosis (AE). The sequencing data can also help trace the release source of cell-free Echinococcus spp. DNA from the genome. According to the mapping results of cell-free Echinococcus spp. DNA reads, we found that most of them were from the nuclear genome rather than the mitochondrial genome, and their release position showed an even distribution on the genome. These characteristics of cell-free Echinococcus spp. DNA in echinococcosis patients’ plasma could facilitate their future application in research or clinical settings.

Cytokine profiles in peripheral blood mononuclear cells from patients with cystic echinococcosis

INTRODUCTION

Cystic echinococcosis (CE) is a chronic zoonotic disease caused by the larval stage of Echinococcus granulosus (E. granulosus), which affects domestic and wild carnivores as the definitive host and ungulates as intermediate hosts. In intermediate hosts, both Th1 and Th2 cells are involved in the immune responses to an echinoccocal infection. This study aimed to investigate production of IL-4, IL-10, and IFN-γ cytokines in peripheral blood mononuclear cells (PBMCs) of CE patients before and after surgical treatment.

METHODS

To evaluate cytokine production in response to E. granulosus antigens, we investigated IL-4, IL-10, and IFN-γ production in PBMCs of 20 CE patients in response to hydatid cyst fluid antigen (HCF-Ag) before and after surgical treatment using ELISA.

RESULTS

The mean IL-4 production from HCF-Ag stimulated PBMCs was significantly decreased (p < 0.05), while IFN-γ was significantly increased in HCF-Ag stimulated PBMCs in patients after surgery (p = 0.005). Furthermore, our results showed that there is no significant difference between IL-10 production in patients before and after treatment (p = 0.562).

CONCLUSIONS

Our data Indicated production of IL-4 in cultured PBMCs of CE patients stimulated with HCF-Ag was decreased significantly. While, production of IFN-γ was increased significantly in responses to HCF Ag after surgery. We concluded that the evaluation of IL-4 and IFN-γ in HCF-Ag stimulated PBMCs of CE patients should be considered as a useful marker in the follow up of patients with cystic echinococcosis.

Elevated incidence of alveolar echinococcosis in immunocompromised patients

Introduction

Recent experimental data has revealed that the course of alveolar echinococcosis (AE) depends on adaptive immunity. For this study, we aimed to analyze the incidence and outcome of AE in immunocompromised humans.

Material and methods

Retrospective analysis of 131 patients with a median age of 54 years treated for AE between 1971 and 2017 at a Swiss tertiary referral Centre. Fifty-two percent were females and 65 patients (50%) were diagnosed incidentally. Fourteen patients (16%) were operated on laparoscopically. Overall, median follow-up was 48 months.

Results

New diagnoses have increased fourfold in immunocompetent and tenfold in immunocompromised patients in the past decade (p ≤ 0.005). Forty-one patients (31.3%) had co-existing or previous immunosuppressive conditions including 16 malignancies (36%), 11 auto-immune diseases or immunosuppressive therapies (31%), 5 infectious diseases (11%), 4 chronic asthma conditions (9%), 2 previous transplantations (4%) and 4 other immunocompromising conditions (9%). Serum levels of anti-Em18, −Em2 and -EgHF antibodies were neither associated with immunocompetence at diagnosis nor during follow-up, but significantly decreased after treatment with benzimidazole (n = 43) or surgery (n = 88) in all patients. Adjuvant therapy for ≥1 year (p = 0.007) with benzimidazole and resection status (R0) (p = 0.002) were both correlated with recurrence-free survival. Survival at 5 and 10 years after surgery was 97% and 94%, respectively, and after conservative treatment 91% and 73%, respectively. Curative surgery (p = 0.014) and immunocompetence (p = 0.048) correlated significantly with overall survival.

Conclusion

The incidence of human AE has increased over the last 2 decades with surgical interventions resulting in excellent outcomes. We have observed an association of immunosuppressive conditions with both incidence and survival of AE eventually justifying the implementation of a screening program for patients at risk in endemic regions.

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Alveolar echinococcosis incidence increased significantly in Switzerland.

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Immunosuppression may lead to an increased susceptibility for the disease.

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Coexisting immunosuppressive conditions lead to worse survival of AE.

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Adjuvant treatment with benzimidazole increases recurrence-free survival.

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Resections with sufficient safety margin improve recurrence-free survival.

Diagnostic and follow-up performance of serological tests for different forms/courses of alveolar echinococcosis

Diagnosis of alveolar echinococcosis (AE) is predominantly based on imaging procedures combined with immunodiagnostic testing. In the present study, we retrospectively analyzed the performance of four serological tests (EgHF-ELISA, Em2-ELISA, recEm18-ELISA and Em-Immunoblotting) for initial diagnosis and subsequent monitoring of AE patients. Overall, 101 AE patients were included, grouped according to treatment options and immune status as follows: (A) curative surgical treatment (n = 45 patients), (B) non-radical or palliative surgical treatment (n = 11), (C) benzimidazoles only (n = 20), (D) immunocompromised with radical surgical treatment (n = 11), (E) immunocompromised with benzimidazoles only (n = 4), and finally a group of 10 AE patients (F) that were considered to present so-called “abortive” lesions. Initial (i.e. pretreatment) ELISA-based diagnosis for patients in groups A to E revealed overall diagnostic sensitivities of 95% for EgHF, 86% for Em2, and 80% for recEm18, respectively. Comparatively, the diagnostic sensitivity of Em-Immunoblotting was higher with an overall value of 98%. In group F, only Em-Immunoblotting had an excellent diagnostic sensitivity (100%), whereas the ELISAs had poor sensitivities of 30% (EgHF- and Em2-ELISA) or even 0% (recEm18-ELISA).

Serological monitoring of AE patients showed a clear association between a curative development of disease (induced either by surgery or benzimidazole medication) and a negativization in the ELISAs. This effect was most pronounced for the recEm18-ELISA, where 56% negativized following diagnosis/treatment, as compared to 36% for the EgHF-ELISA, and 37% for the Em2-ELISA, respectively. After radical surgery, the mean time until negativization in the recEm18-ELISA was 2.4 years (SD 1.6). This was significantly shorter than the mean 3.9 years (SD 2.5) in those AE patients with non-radical, palliative surgery or ABZ treatment who were able to negativize during the study period (p = 0.048).

Conclusively, Em-Immunoblotting appears as the most sensitive test to diagnose active as well as inactive (“abortive”) AE-cases. The inclusion of the ELISAs completes the initial diagnostic picture and offers valuable additional information. Conversely, recEm18-ELISA appears as the currently best serological tool to monitor a regressive and putatively curative course of AE in treated patients.

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EgHF-ELISA plus Em-Immunoblotting results in most sensitive initial AE serodiagnosis.

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Em2- and recEm18-ELISA allow differentiation between AE and CE.

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recEm18-ELISA is currently the best monitoring test for assessing curative course of AE.

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Presumably inactive (“abortive”) AE cases were all positive by Em-Immunoblotting.

Echinococcosis: Advances in the 21st Century

Echinococcosis is a zoonosis caused by cestodes of the genus Echinococcus (family Taeniidae). This serious and near-cosmopolitan disease continues to be a significant public health issue, with western China being the area of highest endemicity for both the cystic (CE) and alveolar (AE) forms of echinococcosis. Considerable advances have been made in the 21st century on the genetics, genomics, and molecular epidemiology of the causative parasites, on diagnostic tools, and on treatment techniques and control strategies, including the development and deployment of vaccines. In terms of surgery, new procedures have superseded traditional techniques, and total cystectomy in CE, ex vivo resection with autotransplantation in AE, and percutaneous and perendoscopic procedures in both diseases have improved treatment efficacy and the quality of life of patients. In this review, we summarize recent progress on the biology, epidemiology, diagnosis, management, control, and prevention of CE and AE. Currently there is no alternative drug to albendazole to treat echinococcosis, and new compounds are required urgently. Recently acquired genomic and proteomic information can provide a platform for improving diagnosis and for finding new drug and vaccine targets, with direct impact in the future on the control of echinococcosis, which continues to be a global challenge.

Lateral flow dipstick antigen assay for human cystic echinococcosis

Cystic echinococcosis (CE) is a neglected zoonotic disease with a worldwide distribution and is a major public health problem in some areas. Diagnosis of CE is mainly based on clinical symptoms, imaging and serological testing, however, improvement in serodiagnosis is still needed. This study was aimed at detecting circulating Echinococcus antigen in CE patients using a lateral flow dipstick (LFD) assay. Three types of hydatid antigens i.e. hydatid cyst fluid (HCF), native antigen B (nAgB) and recombinant antigen B (rAgB) were prepared and polyclonal rabbit antiserum was raised against each antigen. Purified IgG fractions were prepared and a portion was conjugated to gold nanoparticles. After a series of optimizations, a final antigen detection LFD assay was developed using a combination of anti-nAgB-IgG and gold-conjugated anti-HCF-IgG. Evaluation of the assay showed that 27 out of 35 (77%) serum samples from CE patients gave positive results. Meanwhile, the test showed a diagnostic specificity of 82% when tested with sera from 38 healthy individuals and 13 patients with other parasitic diseases. In conclusion, the antigen detection LFD assay seemed to be useful for diagnosis of CE and possibly for post-treatment follow-up, and merit further evaluation studies. We foresee that it may improve serodiagnosis of CE when used in tandem with an antibody detection test.

Foxp3+ T Regulatory Cells as a Potential Target for Immunotherapy against Primary Infection with Echinococcus multilocularis Eggs

Alveolar echinococcosis (AE) is a lethal disease caused by infection with the metacestode stage of the helminth Echinococcus multilocularis, which develops into a tumorlike mass in susceptible intermediate hosts. The growth potential of this parasite stage is directly linked to the nature of the surrounding periparasitic immune-mediated processes. In a first step (experiment 1), mice were orally infected with E. multilocularis eggs, to be used for assessing the hepatic expression profiles of 15 selected cytokine and chemokine genes related to acquired immunity from 21 to 120 days postinfection. The early stage of infection in immunocompetent animals was marked by a mixed Th1/Th2 immune response, as characterized by the concomitant presence of gamma interferon (IFN-γ) and interleukin-4 (IL-4) and their related chemokines. At the late stage of AE, the profile extended to a combined tolerogenic mode including Foxp3, IL-10, and transforming growth factor beta (TGF-β) as key components. In a second step (experiment 2), the effect of T regulatory cell (Treg) deficiency on metacestode growth was assessed in E. multilocularis-infected DEREG (depletion of regulatory T cells) mice upon induction of Treg deficiency with diphtheria toxin (DT). The parasite lesions were significantly smaller in the livers of treated mice than in corresponding control groups. Foxp3⁺ Tregs appear to be one of the key players in immune-regulatory processes favoring metacestode survival by affecting antigen presentation and suppressing Th1-type immune responses. For these reasons, we suggest that affecting Foxp3⁺ Tregs could offer an attractive target in the development of an immunotherapy against AE.

Quantitative characterization and diagnosis via hard X-ray phase-contrast microtomography

Nondestructive three-dimensional (3D) micromorphological imaging technique is essential for hepatic alveolar echinococcosis (HAE) disease to determine its damage level and early diagnosis, assess relative drug therapy and optimize treatment strategies. However, the existing morphological researches of HAE mainly depend on the conventional CT, MRI, or ultrasound in hospitals, unfortunately confronting with the common limit of imaging resolution and sensitivity, especially for tiny or early HAE lesions. Now we presented a phase-retrieval-based synchrotron X-ray phase computed tomography (PR-XPCT) with striking contrast-to-noise ratio and high-density resolution to visualize the HAE nondestructive 3D structures and quantitatively segment different pathological characteristics of HAE lesions without staining process at the micrometer scale. Our experimental results of the HAE rat models at early and developed pathological stages and albendazole liposome (L-ABZ) therapeutic feeding models successfully exhibited the different HAE pathological 3D morphological and microstructural characteristics with excellent contrast and high resolution, demonstrating its availability and superiority. Moreover, we achieved the quantitative statistics and analysis of the pathological changes of HAE lesions at different stages and L-ABZ therapeutic evaluation, helpful to understanding the development and drug treatment of HAE disease. The PR-XPCT-based quantitative segmentation and characterization has a great potential in detection and analysis of soft tissue pathological changes, such as different tumors.

Plasma IL-23 and IL-5 as surrogate markers of lesion metabolic activity in patients with hepatic alveolar echinococcosis

Fluorodeoxyglucose (FDG) uptake by alveolar echinococcosis (AE) liver lesions is a signal of their metabolic activity and of disease progression. In order to find a surrogate marker for this status, we investigated whether parameters of the peripheral and/or periparasitic immune responses were associated with metabolic activity in a prospective case-control study of 30 AE patients and 22 healthy controls. Levels of 18 cytokines and chemokines, representative of innate and adaptive immune responses, were assessed in plasma and peripheral cells of two groups of patients with (MAAE) and without (MIAE) metabolically active lesions, and in the liver of MAAE patients. Mixed cytokine profile was observed in the peripheral blood of AE patients, with a predominance of Th2, Th17 and Treg responses. Among the detected markers only plasma IL-5 and IL-23, more elevated in MAAE patients, were found discriminant. Discrimination between MAAE and MIAE patients obtained by using IL-23 was improved when IL-5 was used in combination. The combination of elevated levels of IL-5 and IL-23 is significantly associated with FDG uptake at PET scan. It offers a new tool for the follow-up of AE patients which could substitute to FDG-PET whenever non-available to assess disease progression.

Screening of antigenic vesicular fluid proteins of Echinococcus multilocularis as potential viability biomarkers to monitor drug response in alveolar echinococcosis patients

PURPOSE

The only drugs available to treat alveolar echinococcosis (AE) are mostly parasitostatic and in many cases prescribed for life. Decision criteria for discontinuation rely on the absence of parasitic viability. The aim of the present study is to search for candidate proteins that may exhibit good potential as biomarkers for viability.

EXPERIMENTAL DESIGN

Sixteen serum samples (five healthy controls, 11 patients with AE), are used. AE-patients are classified into three groups "Cured" (n = 2), "ABZ-responders" (n = 4) and "ABZ-nonresponders" (n = 5). Immunoreactive proteins from vesicular fluid (VF) are identified and quantified by LC-MS/MS analysis after immunoprecipitation (IP) using all 16 serum samples.

RESULTS

Shotgun analysis of VF lead to the identification of 107 E. multilocularis proteins. Comparative proteomics reveal nine proteins more abundant in IP eluates from ABZ-nonresponder patients (cathepsin b, prosaposin a preprotein, actin modulator protein, fucosidase alpha L1 tissue, gluthatione-S-tranferase, beta galactosidase, elongation factor 2, H17g protein tegumental antigen, and NiemannPick C2 protein).

CONCLUSIONS AND CLINICAL RELEVANCE

Detection of antibodies against these proteins by ELISA could be helpful to monitor the course of alveolar echinococcosis under albendazole (ABZ) treatment.

Laboratory Diagnosis of Echinococcus spp. in Human Patients and Infected Animals

Among the species composing the genus Echinococcus, four species are of human clinical interest. The most prevalent species are Echinococcus granulosus and Echinococcus multilocularis, followed by Echinococcus vogeli and Echinococcus oligarthrus. The first two species cause cystic echinococcosis (CE) and alveolar echinococcosis (AE) respectively. Both diseases have a complex clinical management, in which laboratory diagnosis could be an adjunctive to the imaging techniques. To date, several approaches have been described for the laboratory diagnosis and followup of CE and AE, including antibody, antigen and cytokine detection. All of these approaches are far from being optimal as adjunctive diagnosis particularly for CE, since they do not reach enough sensitivity and/or specificity. A combination of several methods (e.g., antibody and antigen detection) or of several (recombinant) antigens could improve the performance of the adjunctive laboratory methods, although the complexity of echinococcosis and heterogeneity of clinical cases make necessary a deep understanding of the host-parasite relationships and the parasite phenotype at different developmental stages to reach the best diagnostic tool and to make it accepted in clinical practice. Standardization approaches and a deep understanding of the performance of each of the available antigens in the diagnosis of echinococcosis for the different clinical pictures are also needed. The detection of the parasite in definitive hosts is also reviewed in this chapter. Finally, the different methods for the detection of parasite DNA in different analytes and matrices are also reviewed.

Assessment of Vascularity in Hepatic Alveolar Echinococcosis: Comparison of Quantified Dual-Energy CT with Histopathologic Parameters

Purpose

To investigate whether dual-energy computer tomography(DECT) could determine the angiographic vascularity of alveolar echinococcosis lesions by comparing the quantitative iodine concentration (IC) with the microvascular density (MVD).

Material and Methods

Twenty-five patients (16 men, 9 women; mean age, 40.9 ± 13.8 years) with confirmed hepatic alveolar echinococcosis (HAE) underwent DECT of the abdomen, consisting of arterial phase (AP), portal venous phase (PVP), and delayed phase (DP) scanning, in dual-source mode (100 kV/140 kV). Image data were processed with a DECT software algorithm that was designed for the evaluation of iodine distribution in the different layers (marginal zone, solid and cystic) of the lesions. The CT patterns of HAE lesions were classified into three types: solid type, pseudocystic type and ‘geographic map’ (mixed) type. The IC measurements in different layers and different types of lesions were statistically compared. MVD was examined using CD34 immunohistochemical staining of the resected HAE tissue and scored based on the percentage of positively stained cells and their intensity. Pearson’s correlation analysis was used to evaluate the potential correlation between DECT parameters and MVD.

Results

A total of 27 HAE lesions were evaluated, of which 9 were solid type, 3 were pseudocystic type and 15 were mixed type. The mean lesion size was 100.7 ± 47.3 mm. There was a significant difference in the IC measurements between different layers of HAE lesions during each scan phase (p < 0.001). The IC in the marginal zone was significantly higher than in the solid and cystic components in AP (2.15 mg/mL vs. 0.17 or 0.01 mg/mL), PVP (3.08 mg/mL vs. 0.1 or 0.02 mg/mL), and DP (2.93 mg/mL vs. 0.04 or 0.02 mg/mL). No significant difference was found among the different CT patterns of HAE lesions. Positive expression of CD34 in the marginal zones surrounding HAE lesions was found in 92.5% (25/27) of lesions, of which 18.5% (5/27) were strongly positive, 62.7% (17/27) were moderately positive, and 11.1% (3/27) were weakly positive. In contrast, 7.4% (2/27) of the lesions were negative for CD34. There was a positive correlation between IC measurements and MVD in the marginal zone of HAE lesions (r = 0.73, p < 0.05).

Conclusions

The DECT quantitative iodine concentration was significantly correlated with MVD in the marginal zones surrounding HAE lesions. Dual-energy CT using a quantitative analytic methodology can be used to evaluate the vascularity of AE.

Sensing parasites: Proteomic and advanced bio-detection alternatives

Parasitic diseases have a great impact in human and animal health. The gold standard for the diagnosis of the majority of parasitic infections is still conventional microscopy, which presents important limitations in terms of sensitivity and specificity and commonly requires highly trained technicians. More accurate molecular-based diagnostic tools are needed for the implementation of early detection, effective treatments and massive screenings with high-throughput capacities. In this respect, sensitive and affordable devices could greatly impact on sustainable control programmes which exist against parasitic diseases, especially in low income settings. Proteomics and nanotechnology approaches are valuable tools for sensing pathogens and host alteration signatures within microfluidic detection platforms. These new devices might provide novel solutions to fight parasitic diseases. Newly described specific parasite derived products with immune-modulatory properties have been postulated as the best candidates for the early and accurate detection of parasitic infections as well as for the blockage of parasite development. This review provides the most recent methodological and technological advances with great potential for bio-sensing parasites in their hosts, showing the newest opportunities offered by modern "-omics" and platforms for parasite detection and control.

Clinical presentation, diagnosis, therapy and outcome of alveolar echinococcosis in dogs

Alveolar echinococcosis (AE), a parasitic disease primarily of the liver caused by the larval stage of Echinococcus multilocularis, is highly endemic in Switzerland. In contrast to well-established management protocols in people, little is known with regard to optimal treatment strategies in dogs. The objective of this study was to describe the clinical signs and diagnostic procedures in dogs with AE and to evaluate outcome following medical treatment alone or surgery and medical treatment. Of 23 putative AE cases between 2004 and 2014, 20 were classified as confirmed (n=18) or probable (n=2) AE, based on abdominal ultrasound, serology, cytology, histology and/or PCR. Most dogs presented with abdominal distension in an advanced stage of disease. Dogs receiving specific treatment (radical or debulking surgery together with medical treatment, or medical treatment alone) survived longer than dogs left untreated, but no difference was found between treatment types. Survival at one year was associated with absence of free abdominal fluid, absence of abdominal distension and treatment of any type. However, dogs treated with debulking surgery all faced relapse. Findings of this study suggest that in AE-affected dogs for which a therapeutic approach is regarded appropriate by owners and veterinarians, radical surgical resection and medical treatment or, if total resection is not possible, medical treatment alone should be considered. However, studies on larger numbers of dogs are necessary before definitive treatment recommendations can be made.

In vivo activity of albendazole in combination with thymol against Echinococcus multilocularis

Human alveolar echinococcosis (AE) is caused by the fox tapeworm Echinococcus multilocularis and is usually lethal if left untreated. The current strategy for treating human AE is surgical resection of the parasite mass complemented by chemotherapy with benzimidazole compounds. However, reliable chemotherapeutic alternatives have not yet been developed stimulating the research of new treatment strategies such as the use of medicinal plants. The aim of the current study was to investigate the efficacy of the combination albendazole (ABZ)+thymol on mice infected with E. multilocularis metacestodes. For this purpose, mice infected with parasite material were treated daily for 20 days with ABZ (5 mg/kg), thymol (40 mg/kg) or ABZ (5 mg/kg)+thymol (40 mg/kg) or left untreated as controls. After mice were euthanized, cysts were removed from the peritoneal cavity and the treatment efficacy was evaluated by the mean cysts weight, viability of protoscoleces and ultrastructural changes of cysts and protoscoleces. The application of thymol or the combination of ABZ+thymol resulted in a significant reduction of the cysts weight compared to untreated mice. We also found that although ABZ and thymol had a scolicidal effect, the combination of the two compounds had a considerably stronger effect showing a reduction in the protoscoleces viability of 62%. These results were also corroborated by optical microscopy, SEM and TEM. Protoscoleces recovered from ABZ or thymol treated mice showed alterations as contraction of the soma region, rostellar disorganization and presence of blebs in the tegument. However both drugs when combined lead to a total loss of the typical morphology of protoscoleces. All cysts removed from control mice appeared intact and no change in ultrastructure was detected. In contrast, cysts developed in mice treated with ABZ revealed changes in the germinal layer as reduction in cell number, while the treatment with thymol or the ABZ+thymol combination predominantly showed presence of cell debris. On the other hand, no differences were found in alkaline phosphatase (AP), glutamate oxaloacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT) activities between control and treated mice, indicating the lack of toxicity of the different drug treatments during the experiment. Because combined ABZ+thymol treatment exhibited higher treatment efficiency compared with the drugs applied separately against murine experimental alveolar echinococcosis, we propose it would be a useful option for the treatment of human AE.