Optimizing sheep B-cell epitopes in Echinococcus granulosus recombinant antigen P29 for vaccine development

Background

Echinococcus granulosus is a widespread zoonotic parasitic disease, significantly impacting human health and livestock development; however, no vaccine is currently available for humans. Our preliminary studies indicate that recombinant antigen P29 (rEg.P29) is a promising candidate for vaccine.

Methods

Sheep were immunized with rEg.P29, and venous blood was collected at various time points. Serum was isolated, and the presence of specific antibodies was detected using ELISA. We designed and synthesized a total of 45 B cell monopeptides covering rEg.P29 using the overlap method. ELISA was employed to assess the serum antibodies of the immunized sheep for recognition of these overlapping peptides, leading to the preliminary identification of B cell epitopes. Utilizing these identified epitopes, new single peptides were designed, synthesized, and used to optimize and confirm B-cell epitopes.

Results

rEg.P29 effectively induces a sustained antibody response in sheep, particularly characterized by high and stable levels of IgG. Eight B-cell epitopes of were identified, which were mainly distributed in three regions of rEg.P29. Finally, three B cell epitopes were identified and optimized: rEg.P2971-90, rEg.P29151-175, and rEg.P29211-235. These optimized epitopes were well recognized by antibodies in sheep and mice, and the efficacy of these three epitopes significantly increased when they were linked in tandem.

Conclusion

Three B-cell epitopes were identified and optimized, and the efficacy of these epitopes was significantly enhanced by tandem connection, which indicated the feasibility of tandem peptide vaccine research. This laid a solid foundation for the development of epitope peptide vaccine for Echinococcus granulosus.

How tapeworms interact with cancers: a mini-review

Cancer is one of the leading causes of death, with an estimated 19.3 million new cases and 10 million deaths worldwide in 2020 alone. Approximately 2.2 million cancer cases are attributed to infectious diseases, according to the World Health Organization (WHO). Despite the apparent involvement of some parasitic helminths (especially trematodes) in cancer induction, there are also records of the potential suppressive effects of helminth infections on cancer. Tapeworms such as Echinococcus granulosus, Taenia crassiceps, and more seem to have the potential to suppress malignant cell development, although in a few cases the evidence might be contradictory. Our review aims to summarize known epidemiological data on the cancer-helminth co-occurrence in the human population and the interactions of tapeworms with cancers, i.e., proven or hypothetical effects of tapeworms and their products on cancer cells in vivo (i.e., in experimental animals) or in vitro. The prospect of bioactive tapeworm molecules helping reduce the growth and metastasis of cancer is within the realm of future possibility, although extensive research is yet required due to certain concerns.

Echinococcus granulosus cyst fluid inhibits inflammatory responses through inducing histone demethylase KDM5B in macrophages

BACKGROUND

Echinococcus granulosus cyst fluid (EgCF) weakens macrophage inflammatory responses, thereby enabling the parasite to evade the immune system. However, the role of histone modification in this process remains to be explored.

METHODS

The levels of IL-6, TNF-α, IL-10, H3K4me3, and KDM5B were detected using quantitative real-time PCR, ELISA, and Western blotting. The enrichment of H3K4me3 and KDM5B at the promoter of inflammatory factors was detected by chromatin immunoprecipitation.

RESULTS

Based on EgCF-stimulated macrophage models, we found that EgCF significantly inhibited mRNA expression and protein secretion of IL-6 and TNF-α and upregulated mRNA expression of IL-10 under the influence of TLR4. EgCF lowered the level of H3K4me3 and promoted the transcription and protein stability of histone demethylase KDM5B. Chromatin immunoprecipitation analysis revealed that EgCF suppressed the enrichment of H3K4me3 modification at the promoters of TNF-α and IL-6 and downregulated their expression in macrophages. Additionally, the inhibition of KDM5B activity by CPI-455 weakened the anti-inflammatory effect of EgCF.

CONCLUSIONS

Our findings demonstrate a novel mechanism through which EgCF promotes KDM5B expression and inhibits the enrichment of H3K4me3 at the promoters of inflammatory cytokines to suppress the inflammatory response.

Complicated Clinical Course of a Patient with Multivisceral Cystic Echinococcosis Requiring Extensive Surgical and Medical Treatment

Cystic echinococcosis is an often-overlooked condition that otherwise negatively impacts both the individual and the community, prompting major public health concerns. Early diagnosis and treatment, as well as collaboration between specialties including surgery and parasitology, are essential for avoiding complications and disease relapse. To better illustrate this, we present the case of an elderly person with a rare localization of the disease at the muscular level. The patient underwent numerous surgical interventions, and received multiple courses of antiparasitic treatment over the course of 40 years as a result of the multivisceral dissemination of the parasite.

The role of memory T cells in Echinococcus granulosus-induced sensitization

OBJECTIVE

To investigate the changes in memory T cells and the related factors in mice by the establishment of a BALB/c mouse model of Echinococcus granulosus-induced sensitization.

METHODS

A sensitized BALB/c mouse model was established by intraperitoneal injection of E. granulosus. A control group (CTRL), a nonsensitized group infected with E. granulosus (CE), and a sensitized group infected with E. granulosus (ANPC) were set up. The pathological changes in lung tissue in mice, the change in memory T cells (CD4 Tm), and the change in peripheral blood nucleated interleukin-23 (IL-23) were detected using HE staining, flow cytometry, and liquid-phase multiple protein quantification techniques, respectively.

RESULTS

The individual percentage of mouse memory T cells was 9.14 ± 0.45, 25.23 ± 0.17, and 13.29 ± 0.32 in the CTRL, CE, and ANPC groups, respectively. The percentage of memory T cells in the ANPC group was higher than that in the CTRL group (t = 18.410, p < .001) but lower than that in the CE group (t = -80.147, p < .001). The levels of IL-23 in peripheral blood of mice in the CTRL, CE, and ANPC groups were 225.76 ± 27.16, 359.21 ± 28.67, and 215.69 ± 22.69, respectively. The level of IL-23 in peripheral blood of mice in the ANPC group was lower than that in the CE group (t = 9.609, p < .001), and there was no statistical difference with the CTRL group (t = 0.697, p = .502).

CONCLUSION

In the BALB/c mouse model of E. granulosus-induced sensitization, the expression of IL-23 in peripheral blood increased, and the memory T cell proliferated and became activated; there was a decrease in the content of IL-23 in peripheral blood and number of activated memory T cells in the sensitization group infected with E. granulosus. The E. granulosus-induced allergic reaction was related to IL-23 and the activation of memory T cells.

What about the Cytoskeletal and Related Proteins of Tapeworms in the Host's Immune Response? An Integrative Overview

Recent advances have increased our understanding of the molecular machinery in the cytoskeleton of mammalian cells, in contrast to the case of tapeworm parasites, where cytoskeleton remains poorly characterized. The pertinence of a better knowledge of the tapeworm cytoskeleton is linked to the medical importance of these parasitic diseases in humans and animal stock. Moreover, its study could offer new possibilities for the development of more effective anti-parasitic drugs, as well as better strategies for their surveillance, prevention, and control. In the present review, we compile the results of recent experiments on the cytoskeleton of these parasites and analyze how these novel findings might trigger the development of new drugs or the redesign of those currently used in addition to supporting their use as biomarkers in cutting-edge diagnostic tests.

Molecular characterization and serodiagnostic evaluation of the Echinococcus ortleppi recombinant glutaredoxin 1 protein for cystic echinococcosis in buffalo (Bubalus bubalis)

Cystic echinococcosis (CE), caused by the metacestode of Echinococcus granulosus sensu lato (s.l.), adversely affects the physiology of the vital organs in which they grow. Condemnation of meat causes substantial economic loss to the livestock industry. Conventionally the infection is detected by necropsy as serological diagnosis of the infection in livestock is ambiguous. Identification of specific diagnostic antigens would be a substitute for the cyst fluid antigens which lack adequate diagnostic sensitivity and specificity. BLAST analysis supported by the negligible pairwise nucleotide distance of the 389 nt COX1, 489 nt NAD1, and 425 nt ITS1 with the related sequences of E. ortleppi ascertained the association of E. ortleppi with CE in buffaloes. Given the extensive distribution of glutaredoxin 1 in every developmental stage of Echinococcus granulosus s.l that makes it an ideal serodiagnostic antigen for CE, we expressed the 14 kDa E. ortleppi glutaredoxin 1 (rEoGrx1) protein in E. coli BL21 (DE3) and tested a total of 225 sera samples, including 126 sera samples from the necropsy-positive buffalo, by the rEoGrx1 IgG-ELISA. The ELISA could detect a total of 82/126 sera samples as positive. The diagnostic sensitivity and specificity of the rEoGrx1 IgG-ELISA were 65.1 % and 51.5 %, respectively. The protein showed serological cross-reaction against Fasciola gigantica, Toxoplasma gondii, and Sarcocystis sp. The in silico bioinformatics analysis of the E. ortleppi, F. gigantica, and T. gondii glutaredoxin sequences revealed fully conserved amino acids at positions 11 and 21, the substitution of conserved amino acids at positions 14 and 6, and semi-conserved substitutions at positions 3 and 4, respectively. The findings partly explain the molecular basis of the serological cross-reactivity of the protein.

Eugenol Essential Oil and Nanoemulsion as Antihydatic Agents with Antifibrotic and Immunomodulatory Effects in Cystic Echinococcosis

Conventional scolicidal agents are still unsatisfactory in combating hydatid disease due to their low efficacy and increased drug side effects. Therefore, novel scolicides are required. This study aimed to evaluate the antihydatic and immunomodulatory effects of eugenol essential oil (Eug) and its nanoemulsion (Eug-NE) in cystic echinococcosis (CE). Eug and Eug-NE were administered orally to CE-infected rats and compared to albendazole (ABZ). Hydatid cyst development was assessed based on organ weight and hypertrophy indicators of the infected organs, along with a histopathological and histochemical evaluation of collagen content. The immunomodulatory effects of treatment on CE were evaluated by serum cytokine levels measurement of interferon-γ (IFN-γ) and interleukin (IL)-4 and immunohistochemical (IHC) analysis of signal transducer and activator of transcription 4 (STAT4) and GATA-binding protein 3 (GATA3) markers. Eug-NE was the most effective in reducing the cyst weights, organ weights, and hypertrophy indicators and improving histopathological lesions with reduced collagen content. Eug and Eug-NE significantly increased the IFN-γ levels and decreased the IL-4 levels, while IHC analysis demonstrated a significant reduction in STAT4 and GATA3 expression in all treated groups. Eug and Eug-NE demonstrated antihydatic and preventative effects, with a substantial decrease in liver fibrosis compared to that of ABZ. Besides their promising immunomodulatory effects, their good treatment response suggests their use as alternatives or complementary scolicidal agents in hydatid cyst treatment.

In vitro anticancer activity of hydatid cyst fluid on colon cancer cell line (C26)

Background

Colon cancer is the third most common cancer and the fourth leading cause of death from cancer. Some parasites are introduced as an antineoplastic agents that can inhibit the progress of some cancers. The aim of this study was to investigate the effect of crude hydatid cyst fluid (HCF) on clone cancer cell line (C26).

Methods

HCF was isolated from hydatid cysts by syringe, and at the first, its toxicity was obtained by 2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. Cell cycle analysis and apoptosis were measured by flow cytometer, and also the expression of Bcl-2 Associated X-protein (BAX) and B-cell lymphoma-2 (BCL2) genes was measured by quantitative reverse transcription PCR.

Results

The amount of apoptosis was increased in B antigen-treated cell lines in comparison with the control group. Also, the expression of BAX was increased in the treated group, while the BCL2 expression was decreased in comparison with the control one. Cell cycle analysis in the antigen-treated group compared to the other groups showed that the cells were more in the G0/G1 phase, as well as in the G2/M phase, and fewer cells were in the synthesis phase.

Conclusion

Our finding showed that HCF possibly contains active compounds and can limit the growth and development of C26 cell line by reducing or increasing the genes involved in apoptosis and finally the effect on the cell cycle.

Graphical Abstract

A multi-epitope vaccine GILE against Echinococcus Multilocularis infection in mice

Introduction

The objective of this study is to construct a multi-epitope vaccine GILE containing B-cell and T-cell epitopes against Echinococcus Multilocularis (E. multilocularis) infection based on the dominant epitopes of E. multilocularis EMY162, LAP, and GLUT1.

Methods

The structure and hydrophobicity of GILE were predicted by SWISSMODEL, pyMOL, SOPMA and VMD, and its sequence was optimized by Optimum™ Codon. The GILE gene was inserted into pCzn1 and transformed into Escherichia coli Arctic express competent cells. IPTG was added to induce the expression of recombinant proteins. High-purity GILE recombinant protein was obtained by Ni-NTA Resin. BALB/c mice were immunized with GILE mixed with Freund's adjuvant, and the antibody levels and dynamic changes in the serum were detected by ELISA. Lymphocyte proliferation was detected by MTS. The levels of IFN-g and IL-4 were detected by ELISpot and flow cytometry (FCM). T cells were detected by FCM. The growth of hepatic cysts was evaluated by Ultrasound and their weights were measured to evaluate the immune protective effect of GILE.

Results

The SWISS-MODEL analysis showed that the optimal model was EMY162 _95-104-LAP_464-479-LAP_495-510-LAP_396-410-LAP_504-518-EMY162_112-126. The SOPMA results showed that there were Alpha helix (14.88%), Extended strand (26.25%), Beta turn (3.73%) and Random coil (45.82%) in the secondary structure of GILE. The restriction enzyme digestion and sequencing results suggested that the plasmid pCzn1-GILE was successfully constructed. The SDSPAGE results indicated that the recombinant protein was 44.68 KD. The ELISA results indicated that mice immunized with GILE showed higher levels of serum antibodies compared to the PBS group. The FCM and ELISpot results indicated that mice immunized with GILE secreted more IFN-g and IL-4. Immunization with GILE also led to a significant decrease in the maximum diameter and weight of cysts and stimulated the production of CD4⁺ and CD8⁺ T Cell.

Discussion

A multi-epitope vaccine GILE with good immunogenicity and antigenicity has been successfully constructed in this study, which may provide important theoretical and experimental bases for the prevention and treatment of E. multilocularis infection.

Detection of Echinococcus granulosus sensu lato cysts and seroprevalence of cystic echinococcosis in cattle and camels in Maiduguri Abattoir

Cystic echinococcosis (CE) is a zoonotic disease of great importance worldwide. This study was conducted to determine the prevalence and antigenic profile of Echinococcus cysts (CE cysts) in camels and cattle. The lungs, livers, hearts, and kidneys of 560 animals, comprising 304 camels and 256 cattle slaughtered in the Maiduguri abattoir, were examined for CE. Blood samples were collected for serology. Protein profiles of CE fluids were analyzed using indirect Enzyme Linked Immunosorbent Assay while Sodium Dodecyl Sulphate Polyacrylamide Gel Electrophoresis (SDS-PAGE) was used to characterize the electrophoretic pattern of different CE cyst fluid samples. The overall prevalence of CE was 8.4%, 14.14% (95% CI = 10.65-18.54%) in camels and 1.60% (95% CI = 0.46-4.09%) in cattle. Adult camels 41 (16.21%) (95% CI = 12.15-21.27%) had a higher prevalence than the young camels 2 (3.92%) (95% CI = 0.33-13.97%) (p = 0.038). In cattle, only adults 4 (2.0%) had cysts. Higher prevalence of CE was recorded in male 22 (16.42%) (95% CI = 11.03-23.68%) than female 21 (12.35%) (95% CI = 8.16-18.21%) camels [p = 0.399] while only female cattle 3 (2.2%) had cysts. Higher prevalence of CE was recorded in the livers of 34 (11.18%) (95% CI = 8.08-15.25%) than in the lungs 25 (8.22%) (95% CI = 5.59-11.90%) of camels [p = 0.273]. Of the 47 cysts collected, 43 (91.49%) and 4 (8.51%) were from camels and cattle, respectively. A total of 18 (38.30%) fertile, 17 (36.17%) non-fertile, and 12 (25.53%) calcified cysts were recovered in animals. Overall seroprevalence of 52.63% (95% CI = 47.02-58.18%) and 35.55% (95% CI = 29.93-41.59%) were observed in camels and cattle in this study. The SDS-PAGE of camel CE cyst fluids revealed protein bands at 64kda, 91kda, 160kda, and 200kda molecular units while the purified cyst fluids revealed bands at 64kda, 91kda, 120kda, 160kda, and 200kda. Regular meat inspections and the exclusion of dogs from abattoir premises are strongly encouraged. Investigation into local prevailing factors encouraging transmission should be carried out.

Roles of immune cells in the concurrence of Echinococcus granulosus sensu lato infection and hepatocellular carcinoma

Immune cells are pivotal players in the immune responses against both parasitic infection and malignancies. Substantial evidence demonstrated that there may exist possible relationship between echinococcus granulus sensu lato (E. granulosus s.l.) infection and hepatocellular carcinoma (HCC) development. Thus, this study aimed to observe crucial roles of immune cells in the formation of subcutaneous lesions after transplanting HepG2 cell lines with or without E. granulosus s.l. protoscoleces (PSCs). HepG2 cell lines were subcutaneously injected into nude mice in the control group. In the co-transplantation group, HepG2 cells were subcutaneously co-injected with high dosage of E. granulosus s.l. PSCs. From the 25th day of transplantation, volume of subcutaneous lesions was measured every four days, which were removed at the 37th day for further studies. Basic pathological and functional changes were observed. Moreover, expression of Ki67, Bcl-2, Caspase3, α-smooth muscle actin (α-SMA), T cell markers (CD3, CD4, CD8), PD1/PD-L1, nature killer (NK) cell markers (CD16, CD56) were further detected by immunohistochemical staining and quantitative real-time polymerase chain reaction (qRT-PCR) analysis. Subcutaneous lesions were gradually increased in volume and there occurred pathologically heterogeneous tumor cells, which were more significant in the co-transplantation group. Compared to the control group, expression of proliferation markers Ki67 and Bcl-2 was at higher levels in the co-transplantation group. Reversely, apoptotic marker Caspase3 was highly detected in the control group, suggesting promoting effects of E. granulosus s.l. PSCs on HCC development. Interestingly, subcutaneous lesions of the co-transplantation group were more functional in synthesizing and storing glycogen. Collagen and α-SMA⁺ cells were also at higher levels in the co-transplantation group than those in the control group. Most importantly, co-transplantation of HepG2 cells with E. granulosus s.l. PSCs led to significant increase in the expression of T cell markers, PD1/PD-L1 and NK cells markers. E. granulosus s.l. may have promoting effects on HCC development, which was closely associated with the immune responses of T cells and NK cells.

Promising effects of parasite-derived compounds on tumor regression: a systematic review of in vitro and in vivo studies

The parasites are repeatedly confronting their host to take advantage of nutrients for multiplication and survival. In this sense, a wide spectrum of molecules is released from both sides, with immune-regulatory activity, accompanying this biological battle. Such parasites and their valuable molecules can be directed toward microbial-based cancer therapy. Herein, we contrived a systematic review to gather information on the antitumor activity of parasite-derived compounds. Following systematic search in Web of Science, ScienceDirect, Scopus, PubMed, ProQuest and Embase until 31 December 2019, a total number of 51 articles (54 datasets) were finally included in this review. Thirteen parasitic agents were found to possess possible antitumor activity, comprising protozoan species Toxoplasma gondii, Trypanosoma cruzi, Trichomonas vaginalis, Acanthamoeba castellanii, Besnoitia jellisoni, Leishmania major, Plasmodium yoelii, and Plasmodium lophurae, as well as parasitic helminths Toxocara canis, Echinococcus granulosus, Taenia crassiceps, Trichinella spiralis, and Schistosoma mansoni. Most experiments were done based on antigenic preparations from T. gondii (16 studies), E. granulosus (10 studies), T. spiralis (8 studies), and T. cruzi (6 studies). Possible antitumor properties of the selected parasites were revealed in this review. However, precise molecular basis of anticancer activity for each parasite remains to be elucidated in the future.

Hepatic inflammation and liver fibrogenesis: A potential target for the treatment of cystic echinococcosis-associated hepatic injury

To investigate the effect of cystic echinococcosis (CE) on liver damage, we developed a secondary experimental echinococcosis in Swiss mice by intraperitoneal inoculation of viable protoscoleces. Mice were randomly allocated into three groups: Ctrl group, PBS group, and CE group. Mice were euthanized and associated indications were investigated to evaluate inflammatory and fibrotic responses in liver. Hepatic damage and fibrotic reaction were histologically analyzed. The hepatic expression of iNOS, TNF-α, NF-κβ, vimentin, Bcl-2 and CD68 was evaluated by Immunohistochemical examinations. Interestingly, a significant iNOS, TNF-α, NF-κβ, vimentin, Bcl-2 and CD68 increase levels was observed in liver tissue and pericystic layer of hepatic hydatid cyst and correlate with the abundance of collagen and reticulin fibers. These observations could promote a potential target for the treatment of CE-associated hepatic injury.

Dysregulation of Ovine Toll-Like Receptors 2 and 4 Expression by Hydatid Cyst-Derived Antigens

Background

Cystic echinococcosis (CE) is a zoonotic disease caused by infection with Echinococcus granulosus. Toll-like receptors (TLRs) as the first line of defense against various parasites play a critical role in sensing and triggering anti-parasite responses.

Methods

The study was conducted at the Department of Pathobiology, Faculty of Veterinary Medicine, Ferdowsi University of Mashhad, Iran in 2019. Ovine peripheral blood mononuclear cells (PBMCs) were stimulated with hydatid cyst-derived antigens including hydatid cyst fluid (HCF), germinal layer antigens (GL), somatic and excretory/secretory (ES) products of protoscoleces (PSC). To investigate whether the expression of TLR2 and TLR4 was altered during exposure to these antigens, PBMCs were stimulated with two different concentrations at different time points.

Results

After exposure of PBMCs to ES and somatic antigens of protoscoleces (PSC) the expression of TLR2 and TLR4 was down-regulated in comparison with control group. Similarly, HCF markedly down-regulated TLR2 and TLR4 transcripts independent of dose and time. GL antigens significantly down-regulated TLR2, while TLR4 expression was up-regulated as compared with control group.

Conclusion

Hydatid cyst-derived antigens could dysregulate the expression of TLR2 and TLR4 in ovine PBMCs, suggesting a possible mechanism to suppress host immunity to establish chronic infection.

Molecular characterization and immune protection of the 3-hydroxyacyl-CoA dehydrogenase gene in Echinococcus granulosus

BACKGROUND

Cystic echinococcosis (CE) is a serious parasitic zoonosis caused by the larvae of the tapeworm Echinococcus granulosus. The development of an effective vaccine is one of the most promising strategies for controlling CE.

METHODS

The E. granulosus 3-hydroxyacyl-CoA dehydrogenase (EgHCDH) gene was cloned and expressed in Escherichia coli. The distribution of EgHCDH in protoscoleces (PSCs) and adult worms was analyzed using immunofluorescence. The transcript levels of EgHCDH in PSCs and adult worms were analyzed using quantitative real-time reverse transcription PCR (RT-qPCR). The immune protective effects of the rEgHCDH were evaluated.

RESULTS

The 924-bp open reading frame sequence of EgHCDH, which encodes a protein of approximately 34 kDa, was obtained. RT-qPCR analysis revealed that EgHCDH was expressed in both the PSCs and adult worms of E. granulosus. Immunofluorescence analysis showed that EgHCDH was mainly localized in the tegument of PSCs and adult worms. Western blot analysis showed that the recombinant protein was recognized by E. granulosus-infected dog sera. Animal challenge experiments demonstrated that dogs immunized with recombinant (r)EgHCDH had significantly higher serum IgG, interferon gamma and interleukin-4 concentrations than the phosphate-buffered saline (PBS) control group. The rEgHCDH vaccine was able to significantly reduce the number of E. granulosus and inhibit the segmental development of E. granulosus compared to the PBS control group.

CONCLUSIONS

The results suggest that rEgHCDH can induce partial immune protection against infection with E. granulosus and could be an effective candidate for the development of new vaccines.

The effects of Zataria multiflora aromatic water and nano emulsion of Z. multiflora essential oil on the serum level of IFN-γ and IL-4 in mice with hydatidosis

The aim of the present investigation was to evaluate the impacts of Zataria multiflora aromatic water (ZMAW) and nano emulsion (NE) of Z. multiflora essential oil (ZMEO) on IL-4 (Th2-derived cytokine) and IFN-γ (Th1-derived cytokine) concentrations in mice with hydatidosis. Sixty four healthy BALB/c female mice were intraperitoneally injected by 1500 live protoscoleces of Echinococcus granulosus. Five month after injection, the infected mice were divided into seven treatment groups, including: Albendazole (100 mg/kg), ZMAW (100 ml/L), Albendazole 100 + ZMAW (Albendazole 100 mg/kg and ZMAW 100 ml/L), Albendazole 50 + ZMAW (Albendazole 50 mg/kg and ZMAW 100 ml/L), Albendazole 100 + NE of ZMEO (Albendazole 100 mg/kg and NE of ZMEO 10 ml/L), albendazole 50 + NE of ZMEO (albendazole 50 mg/kg and NE of ZMEO 10 ml/L) and the control group with no treatment. The mice received the ZMAW, NE of ZMEO and/or albendazole through drinking water for 90 days. At the end of treatment (90 days), blood specimens were harvested from all mice. A significant reduction in IL-4 concentration was revealed in the albendazole 50 group + NE of ZMEO, when compared to the control group (P < 0.05). No significant difference was noticed for the IFN-γ concentration between the trial groups. Increased IFN-γ: IL-4 ratio was observed in the albendazole 50 + ZMAW, Albendazole 50 + NE of ZMEO, Albendazole 100 + NE of ZMEO groups in comparison with the control group (P < 0.05). The findings observed in the current study showed that the administration of ZMAW and NE of ZMEO along with albendazole could enhance the IFN-γ: IL-4 ratio (Th1/Th2 balance), which may have therapeutic value in the treatment of hydatid disease.

Extracellular vesicles of Echinococcus granulosus have therapeutic effects in allergic airway inflammation

BACKGROUND

Previous studies have shown that Echinococcus granulosus cystic fluid can alleviate Th2 allergic airway inflammatory responses by increasing the number of CD4⁺ CD25⁺ Foxp3⁺ T (regulatory T; Treg) cells. Parasite-derived extracellular vesicles (EV) are known to not only promote parasite infection by communicating between parasites but also regulate the inflammatory response by acting as an immunomodulatory agent in the host.

METHODS

To evaluate the effect of EV extracted from the cystic fluid of E. granulosus on allergic airway inflammation, gene expression was investigated after administering EV to mouse lung epithelial cells (MLE-12) following 2 h of pretreatment with Aspergillus proteins. An allergic airway inflammation animal model was used to investigate the regulation of the inflammatory response by EV and induced with ovalbumin.

RESULTS

EV treatment significantly reduced airway resistance and the number of eosinophils and other immune cells in the bronchoalveolar lavage fluid and Th2- and Th17-related cytokine levels. EV pretreatment decreased the number of IL-4⁺ CD4⁺ T cells and increased the number of Treg cells in the lung-draining lymph nodes and spleen.

CONCLUSIONS

Echinococcus granulosus cystic fluid derived EV ameliorated Th2 allergic airway inflammatory through Treg cells, similar to whole cystic fluid treatment. Thus, EV may be important immunomodulatory molecules in cystic fluid.

Community Based Assessment of Behavior and Awareness of Risk Factors of Cystic Echinococcosis in Major Cities of Pakistan: A One Health Perspective

Background: The parasitic disease, cystic echinococcosis (CE), is a serious health problem in Pakistan. Risk of disease transmission is increased by economic and political instability, poor living conditions, and limited awareness of hygienic practices. The current study aimed to investigate the community perception and awareness regarding the risk factors of CE in Pakistan, from a One Health perspective. Methods: We conducted a community-based survey involving 454 participants in the major cities of Pakistan. Quantitative data based on knowledge, attitude, and practices (KAP), the One Health concept, risk factors, and community perception of CE among the general population of the major cities of Pakistan were collected. The questions included those related to knowledge, attitude, practices, One Health concept, risk factors, and community perception. The Chi-squared test was applied to determine the associations regarding KAPs across socio-demographic parameters. Results: KAPs had no significant associations with sociodemographic aspects such as age, sex, religion, ethnicity, education, marital status, occupation, or financial status of the participants. The findings indicated a lack of awareness about CE among the participants. Respondents were unaware of the risk factors and the One Health concept of CE. However, the community attitude and perception were positive toward the control of CE. Conclusion: Illiteracy, deficient sanitation systems and lack of awareness are the contributing factors to CE in Pakistan. It is necessary to make the community aware regarding CE and its importance. Increasing this awareness represents an important step toward the eradication and control of CE.

Vaccination with rEGVac elicits immunoprotection against different stages of Echinococcus granulosus life cycle: A pilot study

Vaccination against dog-sheep transmission cycle is necessary to control cystic echinococcosis (CE) infection. A multi-epitope multi-antigenic recombinant vaccine was developed-comprising the three putative vaccine antigens EG95, Eg14-3-3 and EgEnolase-was cloned and expressed. In a pilot experiment, the multi-antigen vaccine was assessed in 15 dogs and 15 sheep (five experimental groups and three animals in each group) by two subcutaneous doses 28 days apart. To evaluate the efficacy of the vaccine candidate first immunological analysis were done comprising IgG and IgE antibodies and the cytokine IL-4 in sera of the immunized dogs and sheep. Serum IgG, IgE, and IL-4, in particular in the dogs, were increased after the two rounds of vaccine candidate injection, while the total number of hydatid cysts was reduced (~85.43%). This pilot trial indicated significant immune protection efficacy against E. granulosus especially in dogs, while its efficacy in sheep was not as high as dogs. The multi-antigenic candidate vaccine is proposed as a protective vaccine modality in both dogs and sheep.

Th1/Th2/Th17 cytokine profile in hepatic cystic Echinococcosis patients with different cyst stages

AIMS

The study aimed to investigate possible correlation between expression level of Th1/Th2/Th17-type profile and cyst viability in the systemic and local immunity of hepatic cystic Echinococcosis (CE) patients.

METHODS AND RESULTS

Expression of Th1-type interleukin (IL)-2, interferon (IFN)-γ, tumour necrosis factor (TNF)-α, Th2-type IL-4, IL-6, IL-10 and Th17-type IL-17A was examined in the serum and liver samples of hepatic CE patients with different cyst stages. Compared with healthy controls, Th1/Th2/Th17-type cytokines were significantly increased in the serum of hepatic CE patients. Moreover, expression of these cytokines was also at higher level in the inflammatory cell band of peri-lesion liver (PL) tissues than that in the adjacent normal (AN) liver tissues. Interestingly, elevation of Th1-type and Th17-type cytokines was more evident in PL tissues of patients with inactive cysts. Relatively, Th2-type cytokines were predominant in PL tissues of patients with active cysts.

CONCLUSION

Our findings provide new insights that Th1/Th2/Th2-type cytokine profile was associated with cyst stages. In hepatic CE patients with inactive cysts, Th1 and Th17-type cytokines were predominant. Comparatively, Th2-type cytokines were more evident in hepatic CE patients with active cysts, which may provide basis for the immune response diversity in hepatic CE patients with different cyst stages.

Modulatory Effects of Echinococcus multilocularis emu-let-7-5p on the Immunological Functions of RAW264.7 Macrophages

Echinococcus multilocularis is a zoonotic tapeworm with great medical significance. In E. multilocularis-infected mice, parasite-derived let-7-5p (emu-let-7-5p) is present in the sera, but its role remains unclear. Using qPCR, ELISA and flow cytometry, the immunomodulatory effects of emu-let-7-5p were in vitro investigated using RAW264.7 macrophages. Compared with the control, emu-let-7-5p significantly downregulated IL-1α (p < 0.05), but anti-inflammatory cytokine genes remained to be stably expressed in the treated macrophages. Moreover, significantly decreased expression of ripk1 and nf-kB, key components in the LPS/TLR4 signaling pathway, was also observed in the emu-let-7-5p-transfected cells (p < 0.05). Furthermore, CD40 was upregulated in these transfected cells (p < 0.05), while CD86, CD54 and CD80 remained unchanged compared that in the control. These results demonstrate a property of emu-let-7-5p in regulation of immune functions of macrophages, making it be possibly involved in the pathogen-host interplay during E. multilocularis infection.

Cystic Echinococcosis/Hydatid Cyst Coinfection with HIV: A Report from Shiraz, Iran

HIV coinfected with other parasitic diseases may cause a serious problem for the patients. A few case reports describing echinococcosis with human immunodeficiency virus (HIV) infection have been reported in the world; however, it has not been reported in Iran, so far. Here, the first case of liver hydatid cyst coinfected with HIV in Iran is reported. The patient is a 46-year-old female HIV-positive based on the laboratory report. Her clinical symptoms included abdominal pain, abdominal enlargement, and anorexia. Ultrasound showed three large hepatic hydatid cysts with hundreds of daughter cysts. Ultrasonography of the cyst revealed it as a CE2 stage according to the WHO classification. The patient went under complete anesthesia followed by complete cyst removal by surgery. Observation of the hydatid cyst fluid using eosin 0.1% revealed more than 70% viable protoscoleces. Histopathology examination, polymerase chain reaction (PCR), and viable protoscoleces confirmed the diagnosis of echinococcosis. The IgG ELISA test with native AgB for E. granulosus infection was also positive. mtDNA amplification using PCR and sequencing showed the cyst as E. granulosus sensu stricto genotype. Our observations show that huge, large, and high-pressure cysts with hundreds of daughter cysts are difficult to be completely removed, and drug treatment has not been able to reduce their size. Therefore, in HIV coinfection with hydatid cyst, surgery is preferable to other treatments.

Fasciola hepatica co-infection enhances Th1 immune response in the adventitial layer of non-fertile Echinococcus granulosus cysts

Cystic echinococcosis is a widespread zoonosis caused by the larval stage of the tapeworm Echinococcus granulosus. In intermediary hosts, two types of echinococcal cysts can be found: fertile, which produce protoscoleces, the infective form of the parasite to dogs; and infertile, that do not present protoscoleces and therefore are not able to continue with the parasite life cycle. The adventitial layer, the local immune response against the cyst, plays an important role in cyst fertility. Grazing cattle can often feature Fasciola hepatica co-infection, a parasite known to modulate the host systemic immune response. In this work the cellular Th1/Th2 immune profiles were evaluated in the adventitial layer of fertile and non-fertile cysts with and without co-infection with Fasciola hepatica. Measuring with immunohistochemistry and qPCR in adventitial layer, we report that non-fertile cysts present higher levels of Th1 cytokines (IFN-γ (P < 0.0001) and TNF-α (P < 0.05)), and fertile cysts have higher levels of Th2 cytokines (IL-4 (P < 0.001)). Co-infection with Fasciola hepatica is associated with a decrease in the expression of IL-4 (P < 0.05) and an increase in the expression of IFN-γ (P < 0.0001) in the adventitial layer of fertile cysts. Non-fertile cysts were associated with higher levels of Th1 cytokines in the adventitial layer, with IFN-γ expression enhanced by F. hepatica co-infection (P < 0.0001), confirming that polyparasitism should be considered in the treatment and control of naturally infected cattle.

Immunization with Hydatid Cyst Wall Antigens Can Inhibit Breast Cancer through Changes in Serum Levels of Th1/Th2 Cytokines

Background

Hydatid cysts are the larval stage of Echinococcus granulosus, which lead to humoral and cellular immune responses in hosts. Such immune responses play a key role in the inhibition of tumor growth and cancers. To test this hypothesis, it was attempted not only to examine the changes in serum level of some Th1 and Th2 cytokines but also to find relationships between the cytokines and cancer in 4T1 breast cancer-bearing mice immunized with hydatid cyst wall (HCW) antigens.

Methods

Six to eight-week-old Balb/c female mice were immunized with alum, PBS and HCW antigens, including crude extract of HCW (laminated layer) 28 and 27 kDa protein bands (upper and lower bands) and then challenged with 4T1 breast cancer cells. The amounts of IL2, TNF-α, IFN-γ (Th1 cytokines), and IL4 (Th2 cytokine) were estimated using ELISA. Correlations between these cytokines and cancer parameters (tumor growth, metastasis, and survival) were determined by Pearson's correlation coefficients.

Results

Overall, HCW antigens increased the amounts of IL2, TNF-α, IFN-γ, and IL4. Pearson's correlation coefficients indicated reverse relationships between changes in amounts of these cytokines and tumor growth/metastasis. However, except for IL-4, all cytokines had a direct relationship with mouse survival.

Conclusions

The results of this study indicated that the inhibition of breast tumor growth and metastasis and improvement of survival in 4T1 mice immunized with HCW antigens, especially laminated layer and 27 kDa protein band can occur through a rise in the levels of cytokines.

Effects of Allium sativum on IFN-γ and IL4 concentrations in mice with cystic echinococcosis

The aim of the current investigation was to assess the impacts of methanolic extract of Allium sativum (MEAS) on IL-4 (a cytokine derived from Th2 cells) and IFN-ɣ (a cytokine derived from Th1 cells) levels in mice infected with Echinococcus granulosus. Sixty healthy BALB/c female mice were used in this study. Each animal was intraperitoneally injected with 1500 protoscoleces. The infected animals were randomly divided into six groups: albendazole (100 mg/kg), MEAS 10 (10 mg/kg), MEAS 20 (20 mg/kg), MEAS 40 (40 mg/kg), MEAS 80 (80 mg/kg) and control group with no treatment. The studied animals received albendazole and/or MEAS through drinking water for 30 days. Serum IFN-γ concentration significantly increased in the MEAS 20 and 80 groups in comparison to the control, albendazole and MEAS 10 groups (P < 0.05). The serum IL-4 level showed no significant difference between the trial groups. The findings of this study showed that MEAS at 20 and 80 mg/kg concentrations enhanced Th1 cell response in mice with cystic echinococcosis.

Recent advances on innate immune pathways related to host-parasite cross-talk in cystic and alveolar echinococcosis

Cystic echinococcosis (CE) and alveolar echinococcosis (AE) are life-threatening parasitic infections worldwide caused by Echinococcus granulosus (sensu lato) and E. multilocularis, respectively. Very little is known about the factors affecting innate susceptibility and resistance to infection with Echinococcus spp. Although benzimidazolic drugs against CE and AE have definitively improved the treatment of these cestodes; however, the lack of successful control campaigns, including the EG95 vaccine, at a continental level indicates the importance of generating novel therapies. This review represents an update on the latest developments in the regulatory functions of innate immune pathways such as apoptosis, toll-like receptors (TLRs), and inflammasomes against CE and AE. We suggest that apoptosis can reciprocally play a bi-functional role among the host-Echinococcus metabolite relationships in suppressive and survival mechanisms of CE. Based on the available information, further studies are needed to determine whether the orchestrated in silico strategy for designing inhibitors and interfering RNA against anti-apoptotic proteins and TLRs would be effective to improve new treatments as well as therapeutic vaccines against the E. granulosus and E. multilocularis.

Cell-mediated and humoral immune profile to hydatidosis among naturally infected farm animals

Background and Aim

Cystic echinococcosis (CE) is a widespread parasitic disease caused by Echinococcus granulosus tapeworm infect different intermediate hosts including sheep, cattle, and camels. The intermediate host's immune response to the hydatid cyst is still conflict and complex. The current study was designed to evaluate the immune response in sera of hydatid naturally infected sheep, cattle, and camels in the form of features of inflammatory cell infiltrations, levels of Th1 and Th2 cytokines, besides the humoral specific immunoglobulin G (IgG) responses.

Materials and Methods

Thirty-nine sheep, 74 cattle, and 79 camels' sera were collected and considered as CE naturally infected and ten samples from each species were graded as non-infected. Lung specimens were collected for histopathological examination. The quantitative concentrations of tumor necrosis factor-α, interleukin (IL)-6, IL-4, and IL-10 were determined. Different antigens were prepared from hydatid cyst; hydatid cyst fluid of lung origin hydatid cyst fluid of liver origin, hydatid cyst protoscoleces of lung origin (HCP-g), hydatid cyst protoscoleces of liver origin, hydatid cyst germinal layer of lung origin, and hydatid cyst germinal layer of liver origin; and characterized by gel electrophoresis and Western blotting analysis. The total specific IgG level against E. granulosus infection was measured using an indirect enzyme-linked immunosorbent assay.

Results

The results indicated that the cellular immune response in the infected tissues was characterized by inflammatory cell penetration. The pro-inflammatory Th1 cytokine profile was predominant in infected animals in comparison with non-infected ones. However, the humoral immune response was seen as a high level of IgG in infected animals. The presented data approved that the HCP-g antigen could be considered as a delegate antigen for all other prepared antigens with an immunoreactive band at molecular weights 32 kDa.

Conclusion

This study provides a fundamental insight into the events that manipulate cellular and humoral immune profiles in an intermediate host; sheep, cattle, and camel that naturally infected with CE. Hence, it was concluded that CE is a constant disease and confirm the reactivity Th1 in combating hydatid cyst. Besides, it could lead to the activation of the humoral immune response in the form of a high level of IgG.

The combination of Cytokines and albendazole therapy for prophylaxis and treatment of experimental/hydatid cyst

Albendazole is appropriate chemotherapy for treatment and prophylaxis of cystic echinococcosis (CE). The recent studies show Cytokine therapy could be useful for chronic and progressive diseases, therefore, the use of cytokine in prophylaxis and treatment of hydatidosis could be considerable. The aim of this study is to evaluate the efficacy of interleukin-12 + interferon-gamma, in combination with albendazole for prophylaxis and treatment of CE in Balb/c mice. Albendazole and cytokines were administrated for prophylaxis and treatment in CE. The efficacy of this agents were determined by measuring of size, weight, number of cysts, histology and lymphocyte response. Lymphocyte stimulation index and production of interleukin-12 and interferon-gamma were measured by MTT assay and ELISA respectively. Combination of albendazole and cytokines was very effective for prophylaxis and treatment in experimental CE.

Bone marrow-derived mesenchymal stem cell (BM-MSC): A tool of cell therapy in hydatid experimentally infected rats

This study aimed to clarify the potentiality of bone marrow mesenchymal stem cells (BM-MSC) transplantation with albendazole (ABZ) on the modulation of immune responses against hydatid cyst antigens and the regeneration of injured livers in experimentally infected rats. Three different antigens of hydatid cyst fluid (HCF), hydatid cyst protoscolex (HCP) and hydatid cyst germinal layer (HCG) were isolated and their antigenic potencies were determined. The ultrasound, immunological and pathological criteria were investigated. Counting of 80% confluence BM-MSC was 4.68 × 104 cells/cm2 with 92.24% viability. Final population doublings score was 65.31 that indicated proliferation and self-renewability. Phenotyping of BM-MSC showed expression of CD73 and CD29 without exhibition of CD34 and CD14. Ultrasound examination showed multiple hydatid cysts in liver with low blood flow and spleenomegaly 8 weeks' post infection. No significant differences were noted in cystic diameter in uni-cyst liver at 2nd and 4th weeks following ABZ treatment while it was significantly decreased (P < 0.05) following transplantation of BM-MSC + ABZ treatment comparing to experimentally infected untreated group. Igs and IgG responses to the three antigens were significantly elevated while elevation in IgM response was only to HCG (P < 0.05). ABZ treatment accompanied with significant decrease in Igs and IgG titers against HCF and HCG only at 4th week post treatment (P < 0.05). However, Igs titer against HCF, HCP and HCG was significantly decreased at the 4th week following transplantation of BM-MSC + ABZ. Interestingly, the combination of BM-MSC + ABZ treatment resulted in reduction of Igs response to HCP to normal level as that of healthy control. Experimental infection resulted in elevation of TNF-α and IL-6 (P < 0.05) while, IL-4 and IL-10 decreased (P < 0.01). After transplantation of BM-MSC + ABZ treatment, serum TNF-α and IL-6 concentrations were reduced (P < 0.05) at both the 2nd and 4th weeks. However, IL-4 and IL-10 concentrations were significantly elevated (P < 0.05) only at 4th week following transplantation of BM-MSC + ABZ treatment. In conclusion, BM-MSC transplantation following ABZ administration can regenerate injured liver tissue without complete disappearance of hydatid cyst. In addition, it can modulate host protective humeral and cell mediated immune responses against hydatid cyst antigens. Therefore, the current study encourages to move to the step of performing clinical trials in humans.

Thioredoxin peroxidase secreted by Echinococcus granulosus (sensu stricto) promotes the alternative activation of macrophages via PI3K/AKT/mTOR pathway

BACKGROUND

Larvae of Echinococcus granulosus (sensu lato) dwell in host organs for a long time but elicit only a mild inflammatory response, which indicates that the resolution of host inflammation is necessary for parasite survival. The recruitment of alternatively activated macrophages (AAMs) has been observed in a variety of helminth infections, and emerging evidence indicates that AAMs are critical for the resolution of inflammation. However, whether AAMs can be induced by E. granulosus (s.l.) infection or thioredoxin peroxidase (TPx), one of the important molecules secreted by the parasite, remains unclear.

METHODS

The activation status of peritoneal macrophages (PMs) derived from mice infected with E. granulosus (sensu stricto) was analyzed by evaluating the expression of phenotypic markers. PMs were then treated in vivo and in vitro with recombinant EgTPx (rEgTPx) and its variant (rvEgTPx) in combination with parasite excretory-secretory (ES) products, and the resulting activation of the PMs was evaluated by flow cytometry and real-time PCR. The phosphorylation levels of various molecules in the PI3K/AKT/mTOR pathway after parasite infection and antigen stimulation were also detected.

RESULTS

The expression of AAM-related genes in PMs was preferentially induced after E. granulosus (s.s.) infection, and phenotypic differences in cell morphology were detected between PMs isolated from E. granulosus (s.s.)-infected mice and control mice. The administration of parasite ES products or rEgTPx induced the recruitment of AAMs to the peritoneum and a notable skewing of the ratio of PM subsets, and these effects are consistent with those obtained after E. granulosus (s.s.) infection. ES products or rEgTPx also induced PMs toward an AAM phenotype in vitro. Interestingly, this immunomodulatory property of rEgTPx was dependent on its antioxidant activity. In addition, the PI3K/AKT/mTOR pathway was activated after parasite infection and antigen stimulation, and the activation of this pathway was suppressed by pre-treatment with an AKT/mTOR inhibitor.

CONCLUSIONS

This study demonstrates that E. granulosus (s.s.) infection and ES products, including EgTPx, can induce PM recruitment and alternative activation, at least in part, via the PI3K/AKT/mTOR pathway. These results suggest that EgTPx-induced AAMs might play a key role in the resolution of inflammation and thereby favour the establishment of hydatid cysts in the host.

Nanostructured lipid carriers of ivermectin as a novel drug delivery system in hydatidosis

Background

The larval stage of the tapeworm Echinococcus granulosus is the causative agent of hydatid disease in humans. This zoonotic parasitic infection remains a major health problem in certain areas of the world where is still endemic. In view of the ineffectiveness of some drug treatments, the surgical removal of cysts remains the preferred treatment option together with the administration of albendazole and mebendazole. However, severe side effects of these drugs have been reported which demands developing new scolicidal agents that confer suitable efficacy and fewer side effects during surgery.

Methods

To that purpose, in the present work we assessed the effectiveness of ivermectin (IVM), a macrocyclic lactone endectocide that has shown to be an effective nematocidal drug against other important parasitic infections. To overcome the limitations observed in some drug formulations and resistance, we used nano lipid carriers (NLCs) as a targeted and sustained drug delivery system for IVM. We evaluated the in vitro cestocidal and apoptotic effects of NLCs-loaded IVM versus IVM by quantifying the expression of caspase-3 mRNA.

Results

We found that after 60 and 120 min of administration, 800 μg/ml and 400 μg/ml NLCs-loaded IVM induced 100% mortality, respectively. On the other hand, the 800 μg/ml of IVM induced 100% mortality rate 150 min after administration. Additionally, we found that NLCs-loaded IVM induced higher mRNA caspase-3 expression suggesting a more potent apoptotic effect on the parasite.

Conclusions

These data suggest that NLCs-loaded IVM may be a promising alternative to current treatments although in vivo studies are needed.

Employing Parasite Against Cancer: A Lesson From the Canine Tapeworm Echinococcus Granulocus

Cystic echinococcosis (CE), a devastating zoonotic condition caused by the tapeworm Echinococcus granulosus, remain a significant public health problem worldwide. However, after a negative correlation between solid tumor and CE has been incidentally discovered, accumulating evidence have suggested that this parasite may induce anticancer effect through activating host immune response and secreting molecules with anticancer potential, which may provide some new understanding for immunotherapy. This article will review the evidence supporting the anticancer effect of E. granulosus and its underlying mechanisms and discuss the possible implications in immunotherapy.

Prevalence and Molecular Characterization of Echinococcus granulosus Sensu Stricto in Northern Xinjiang, China

Echinococcus granulosus is an important zoonotic parasite globally causing cystic echinococcosis (CE) in humans and animals. In this study, prevalence of CE and variation of cox1 gene sequence were analyzed with isolates E. granulosus collected from different areas in northern Xinjiang, China. The survey showed that 3.5% of sheep and 4.1% of cattle were infected with CE. Fragment of cox1 was amplified from all the positive sheep and cattle samples by PCR. In addition, 26 positive samples across the 4 areas were included. The isolates were all E. granulosus sensu stricto (s.s.) containing 15 haplotypes (Hap1-15), and clustered into 2 genotypes, G1 (90.1%, 91/101) and G3 (9.9%, 10/101). Hap1 was the most common haplotype (48.5%, 49/101). Hap9 were found in humans samples, indicating that sheep and cattle reservoir human CE. It is indicate that E. granulosus may impact on control of CE in livestock and humans in the region.

Hepatic echinococcosis: A review

Cystic echinococcosis (CE) is a widely endemic helminthic disease caused by infection with metacestodes (larval stage) of the Echinococcus granulosus tapeworm and transmitted by dogs. E. granulosus are common parasites in certain parts of the world, and are present on every continent with the exception of Antarctica. As a result, a large number of people are affected by CE. In humans, the disease is characterized by slowly growing cyst commonly occurring in liver and lungs. Clinical features are mainly right upper quadrant pain, feeling of lump and enlarged tender liver. The cyst may be complicated by infection or rupture and may lead to anaphylactic reaction. The diagnosis depends on clinical suspicion. They appear in two ways as general (systemic) symptoms, and local symptoms based on the site and organ on which the larva settles. While cysts sometimes recover spontaneously, more severe clinical presentations are observed in immunosuppressed individuals. Ultrasonography supported by serology is the main diagnostic modality. The treatment varies from surgical intervention to minimally invasive treatments (percutaneous drainage) or medical therapies. Surgery is still the best treatment modality. Percutaneous drainage of the cyst is a good option in selected cases. New sensitive and specific diagnostic methods and effective therapeutic approaches against echinococcosis have been developed in the last 10 years.

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Echinococcal cysts, although fairly uncommon, should be considered in the differential diagnosis of hepatic cysts.

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Serum antibody assays generally have low sensitivities, but antigen assays may be of value.

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Imaging is crucial in determining cyst stage, size, location and complications.

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Uncomplicated active cysts can be managed with chemotherapy alone or in combination with a PAIR approach. Inactive cysts can be managed with the “watch-and-wait” strategy.

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Surgery is the first choice when there is cystobiliary fistula and significant extra-hepatic extension with high risk of perforation.

Estimating the prevalence of Echinococcus in domestic dogs in highly endemic for echinococcosis

BACKGROUND

Cystic echinococcosis (CE) and alveolar echinococcosis (AE) are highly endemic in Xiji County of Ningxia Hui Autonomous Region (NHAR) in China where the control campaign based on dog de-worming with praziquantel has been undertaken over preceding decades. This study is to determine the current prevalence of Echinococcus granulosus and E. multilocularis in domestic dogs and monitor the echinococcosis transmission dynamics.

METHODS

Study villages were selected using landscape patterns (Geographic Information System, GIS) for Echinococcus transmission "hot spots", combined with hospital records identifying risk areas for AE and CE. A survey of 750 domestic dogs, including copro-sampling and owner questionnaires, from 25 selected villages, was undertaken in 2012. A copro-multiplex PCR assay was used for the specific diagnosis of E. granulosus and E. multilocularis in the dogs. Data analysis, using IBM SPSS Statistics, was undertaken, to compare the prevalence of the two Echinococcus spp. in dogs between four geographical areas of Xiji by the χ2 test. Univariate analysis of the combinations of outcomes from the questionnaire and copro-PCR assay data was carried out to determine the significant risk factors for dog infection.

RESULTS

The highest de-worming rate of 84.0% was found in the northwest area of Xiji County, and significant differences (P <  0.05) in the de-worming rates among dogs from the four geographical areas of Xiji were detected. The highest prevalence (19.7%, 59/300) of E. multilocularis occurred in northwest Xiji, though the highest prevalence (18.1%, 38/210) of E. granulosus occurred in southwest Xiji. There was no significant difference (P >  0.05) in the prevalence of E. granulosus in dogs from the northwest, southwest, northeast, and southeast of Xiji, but there were significant differences (P <  0.05) between dogs infected with E. multilocularis from the four areas. None of the other independent variables was statistically significant.

CONCLUSIONS

The results from this study indicate a high prevalence of both E. granulosus and E. muiltilocularis in dogs in Xiji County, NHAR. Transmission of E. multilocularis was more impacted by geographical risk-factors in Xiji County than that of E. granulosus. Dogs have the potential to maintain the transmission of both species of Echinococcus within local Xiji communities, and the current praziquantel dosing of dogs appears to be ineffective or poorly implemented in this area.

A 53 KDa Glycan Antigen of Hydatid Cyst Wall May Involve in Evasion from Host Immune System

Background:

Recent studies have shown that similar host glycan antigens are expressed by helminths such as Echinococcus granulosus hydatid cysts to evade from host immune system. In this work to investigate these antigens further, immunological cross-reactivity between human sera and hydatid cyst wall antigens has been investigated.

Materials and Methods:

Hydatid cyst wall antigens were used in enzyme-linked immunosorbent assay and Western immunoblotting and probed with pooled sera of hydatidosis patients and healthy controls. Sodium metaperiodate treatment was used to investigate glycan antigens.

Results:

A band with molecular weight about 53 KDa reacted with both hydatid patients' sera and also normal human sera. It has been shown that this band was a glycan antigen.

Conclusions:

A 53 KDa glycan antigen of hydatid cyst wall that reacted with all human sera may have an important role for evasion from host immune system.

In vivo treatment with IL-17A attenuates hydatid cyst growth and liver fibrogenesis in an experimental model of echinococcosis

We aimed to assess the effect of exogenous Interleukin (IL)-17A in experimental model of echinococcosis. Swiss mice were inoculated intra-peritoneally with viable protoscoleces (PSCs). Then, IL-17A was administered at 100, 125 or 150 pg/mL two weeks after cystic echinococcosis (CE) induction. Cyst development and hepatic damage were macroscopically and histologically analyzed. We observed that in vivo IL-17A treatment at 100, 125, and 150 pg/mL, reduced metacestode growth by 72.3%, 93.8%, and 96.9%, respectively. Interestingly an amelioration of liver architecture was noted at 125 pg/mL without toxic effect. In this context, we showed less fibrosis reaction and reduced expression of iNOS, TNF-α, NF-κb and CD68 in hepatic parenchyma of treated mice by 125 pg/mL of IL-17A. Collectively, our results indicate an antihydatic effect and immunoprotective properties of IL-17A and suggest its potential therapeutic value against Echinococcus granulosus infection.

Echinococcus granulosus: Cure for Cancer Revisited

Whereas a number of parasites are well recognized risk factors for a number of different cancers in mammalian hosts, there is limited information on the ability of parasitic organisms to induce anticancer effects. There are conflicting reports that echinococcosis, caused by the canine tapeworm Echinococcus granulosus, can decrease or increase cancer risk. This review considers both indirect anticancer effects as the result of adaptive immunity generated against certain echinococcal antigens and the direct effect of molecules released by E. granulosus whose activity directly inhibits cancer cell migration and growth. In conclusion, E. granulosus probably secretes molecules that can be developed as anticancer therapeutics in future.

Modelling the regional vulnerability to Echinococcosis based on environmental factors using fuzzy inference system: A case study of Lorestan Province, west of Iran

Background and aim

Echinococcosis as a zoonosis disease is one of the most important parasitic helminth that is affected by many risk factors such as the environmental factors. Thus, we predicted the regional vulnerability to Echinococcosis based on environmental factors using a fuzzy inference system (FIS) in Lorestan Province.

Methods

Our study was cross-sectional study on 200 patients from Lorestan Province (west of Iran) who underwent surgery for hydatidosis between October 2005 and November 2014. In order to model the vulnerability to Echinococcosis, first we determined the effective environmental variables. In the next step, the FIS was designed and implemented using MATLAB v.2012 software. Thus, definition and determination of linguistic variables, linguistic values, and their range were performed based on expert knowledge. Then, the membership functions of inputs (environmental variables) and output (vulnerability to Echinococcosis) were defined. A fuzzy rules base was formed. Also, the defuzzification of output was done using a centroid defuzzification function. To test the accuracy of the predictive model, we calculated the AUC (to this purpose, we used four different thresholds, 5%, 10%, 15%, and 20%) using IDRISI Selva v.17.0 software.

Results

Based on the results of this study, Aligoudarz and Koohdasht counties were identified as a highest and lowest risk area in Lorestan, respectively. The results showed that a predictive model was more efficient than a random model (AUC>0.5). Also, potential vulnerable areas cover 78.29% at threshold of 5%, 60.72% at threshold of 10%, 43.54% at threshold of 15%, and 39.82% at threshold of 20% of the study area.

Conclusion

According to the success of this research, we emphasized the necessity of attention to fuzzy approach to model vulnerability to hydatidosis. This approach can provide a practical economic basis for making informed preventive services decisions and the allocation of health resources.

A novel B- and helper T-cell epitopes-based prophylactic vaccine against Echinococcus granulosus

Introduction: In this study, we targeted the worm stage of Echinococcus granulosus to design a novel multi-epitope B- and helper T-cell based vaccine construct for immunization of dogs against this multi-host parasite.

Methods: The vaccine was designed based on the local Eg14-3-3 antigen (Ag). DNA samples were extracted from the protoscoleces of the infected sheep’s liver, and then subjected to the polymerase chain reaction (PCR) with 14-3-3 specific forward and reverse primers. For the vaccine designing, several in silico steps were undertaken. Three-dimensional (3D) structure of the local Eg14-3-3 Ag was modeled by EasyModeller software. The protein modeling accuracy was then analyzed via various validation assays. Potential transmembrane helix, signal peptide, post-translational modifications and allergenicity of Eg14-3-3 were evaluated as the preliminary measures of B-cell epitopes (BEs ) prediction. Having used many web-servers, a well-designed process was carried out for improved prediction of BEs. High ranked linear and conformational BEs were utilized for engineering the final vaccine construct. Possible T-helper epitopes (TEs) were identified by the molecular docking between 13-mer fragments of the Eg14-3-3 Ag and two high frequent dog class II MHC alleles (i.e., DLA-DRB1*01101 and DRB1*01501). The epitopes coverage was evaluated by Shannon’s variability plot.

Results: The final designed construct was analyzed based on different physicochemical properties, which was then codon optimized for high-level expression in Escherichia coli k12. This minigene construct is the first dog-specific epitopic vaccine construct that is established based on TEs with high-binding affinity to canine MHC alleles.

Conclusion: This in silico study is the first part of a multi-antigenic vaccine designing work that represents as a novel dog-specific vaccine against E. granulosus. Here, we present key data on the step-by-step methodologies used for designing this de novo vaccine, which is under comprehensive in vivo investigations.

A novel in silico minigene vaccine based on CD4+ T-helper and B-cell epitopes of EG95 isolates for vaccination against cystic echinococcosis

EG95 oncospheral antigen plays a crucial role in Echinococcus granulosus pathogenicity. Considering the diversity of antigen among different EG95 isolates, it seems to be an ideal antigen for designing a universal multivalent minigene vaccine, so-called multi-epitope vaccine. This is the first in silico study to design a construct for the development of global EG95-based hydatid vaccine against E. granulosus in intermediate hosts. After antigen sequence selection, the three-dimensional structure of EG95 was modeled and multilaterally validated. The preliminary parameters for B-cell epitope prediction were implemented such as the possible transmembrane helix, signal peptide, post-translational modifications and allergenicity. The high ranked linear and conformational B-cell epitopes derived from several online web-servers (e.g., ElliPro, BepiPred v1.0, BcePred, ABCpred, SVMTrip, IEDB algorithms, SEPPA v2.0 and Discotope v2.0) were utilized for multiple sequence alignment and then for engineering the vaccine construct. T-helper based epitopes were predicted by molecular docking between the high frequent ovar class II allele (Ovar-DRB1*1202) and hexadecamer fragments of the EG95 protein. Having used the immune-informatics tools, we formulated the first EG95-based minigene vaccine based on T-helper epitope with high-binding affinity to the ovar MHC allele. This designed construct was analyzed for different physicochemical properties. It was also codon-optimized for high-level expression in Escherichia coli k12. Taken all, we propose the present in silico vaccine constructs as a promising platform for the generation of broadly protective vaccines for species and genus-specific immunization of the natural hosts of the parasite.

Comparative proteome profiling of hydatid fluid from Algerian patients reveals cyst location-related variation in Echinococcus granulosus

Human cystic echinococcosis, an endemic zoonosis in Algeria, is caused by larvae of the cestode Echinococcus granulosus. Parasitic modulation of the immune response allows E. granulosus to persist in intermediate hosts. Previous in vitro and in vivo immunological studies have shown differences in host immune responses according to the status and location of the hydatid cysts in the body. In this study, a proteomic analysis of human hydatid fluids was performed to identify the proteins in hydatid cyst fluids. Hydatid fluid was obtained after cystic surgical removal from three patients with these cysts. The study was conducted on fertile hydatid fluids from lungs, vertebra, and infertile paravertebral fluids. Comparisons of the protein compositions of these fluids revealed differences in their protein profiles. These differences are probably related to the cyst location and fertility status of the parasite. Notably, our analysis identified new proteins from the parasite and human host. The identification of host proteins in hydatid fluids indicates that the hydatid walls are permeable allowing a high protein exchange rate between the metacestode and the affected tissue. Interestingly, our study also revealed that parasite antigenic protein expression variations reflect the differences observed in host immunostimulation.

Helminth-induced apoptosis: a silent strategy for immunosuppression

During microbial infections, both innate and adaptive immunity are activated. Viruses and bacteria usually induce an acute inflammation in the first setting of infection, which helps the eliciting an effective immune response. In contrast, macroparasites such as helminths are a highly successful group of invaders known to be capable of maintaining a chronic infestation with the minimum instigation. Undoubtedly, generating such an immunoregulatory environment requires the exploitation of various immunosuppressive mechanisms to debilitate host immunity supporting their survival and replication. Several mechanisms have been recognized whereby helminths prolong their infections including an increase of immunoregulatory cells, inhibition of Th1 or Th2 responses, targeting pattern recognition receptors (PRRs) and lowering the immune cells quantity via induction of apoptosis. Apoptosis is a programmed intracellular process involving a series of consecutive downstream signalling event evolved to cell death. It plays a pivotal role in several immunological reactions in particular deletion of autoreactive immune cells. Helminth-triggered apoptosis in immune cells exhausts host immunity, which paves the way for generating a permissive environment and chronic infection. This review provides a compilation of recent investigations discussing the apoptotic mechanisms exploited by different worms and the immunological consequences of immune cell death. Finally, the anti-cancer effects of some worm-derived molecules due to their apoptotic effects are discussed, highlighting as potentially druggable candidates to combat cancer.

Comparative study on secretome and transmembranome of immature and mature metacestodes of Echinococcus multilocularis

Alveolar echinococcosis (AE) is a worldwide zoonosis caused by E. multilocularis. Humans become infected through oral ingestion of the eggs. Host of E. multilocularis produces immune responses that help to either reject and/or limit the growth of this parasite, and in response the parasite produces molecules against this immune attack. This study identifies candidate key molecules in the early infection phase and the chronic stage of the parasite infestation, through comparison of gene expression of 4- and 16-week metacestodes. First, RNA was isolated from 4- and 16-weeks metacestodes of E. multilocularis (Nemuro strain). Thereafter, clean reads with lengths of 50bp or longer were compared against a reference genome using TopHat. Functional annotation of transcripts of E. multilocularis were investigated using multi-step bioinformatics tools. At the gene ontology (GO) level, 356 and 1774 transmembrane (TM) predicted proteins of the E. multilocularis were mapped to an enhanced 'hydrolase activity' and increased 'transmembrane transporter activity', respectively. In addition, comparison of gene expression level between 4- and 16-week metacestode revealed 168 different expression (DE) genes. This study has demonstrated that, the expression levels of predicted ES and TM proteins in E. multilocularis change in the transformation from one stage to another. Genes that are highly expressed in immature or mature metacestode could be explored as novel candidates for diagnostic antigens and vaccine targets.

Surgically managed human cystic echinococcosis in north-eastern Iran: a single center's experience from 2001 to 2008

Cystic echinococcosis (CE) is a zoonotic parasitic disease caused by the tapeworm Echinococcus granulosus. Although CE has a large geographic distribution, data are lacking on the frequency of infection and epidemiology of CE in many endemic areas of the world, including the Middle East. Demographic and clinical information on surgically managed human CE cases were evaluated from a referral hospital in north-eastern Iran for the years 2001-2008. Of the 400 CE cases, 218 (54.5%) were male. The median age of patients was 35 years (range 2-83 years). The lungs (41.0%) and liver (37.7%) were the most commonly infected organs. However, 12.7% of patients had multiple organ involvement. The majority of cases (54.3%) were diagnosed using ultrasound, with only 12.0% diagnosed with the help of serology. Total white blood cell count was elevated in 26.8% (107/400) of patients, neutrophil count was elevated in 24.0% (96/400) of patients, and eosinophil count was elevated in 13.3% (53/400) of patients. Lymphocyte count was the only complete blood count (CBC) value that differed based on organ location (P = 0.001). Despite some successes in the control of CE, the number of surgical CE cases in north-eastern Iran remains high. Although not diagnostic alone, CBC values allow for clinicians to obtain a more complete clinical picture of CE before, during, and after treatment. While serology has its place, the use of diagnostic imaging continues to be the most commonly used tool for the diagnosis of CE cases.

Association between Echinococcus granulosus infection and cancer risk - a pilot study in Cyprus

BACKGROUND

Infections from microorganisms and parasites have been connected with either increased or decreased cancer risk. The objective of this study was to investigate whether infection by Echinococcus granulosus is associated with cancer risk.

METHODS

We assembled a pilot retrospective cohort of patients who were diagnosed as being infected by E. granulosus in Cyprus between 1930 and 2011. Age/gender-matched non-infected family members and neighbors were selected as references. Medical history was ascertained from each study subject through in-person interview. Cox proportional hazards regression analysis was performed to assess the association of being infected by E. granulosus with cancer risk.

RESULTS

Individuals with prior infection by E. granulosus (n=249) were more likely to have cancer compared to those without infection (n=753), 11.65% vs. 8.37% (p=0.0492). Survival analysis also showed that subjects with prior infection had a higher risk for developing cancer. The hazards ratio (HR) was 1.595, [95% confidence interval (CI) between 1.008 and 2.525]. The risk ratio did not change significantly (HR=1.536; 95% CI: 0.965-2.445) after adjusting for gender, year of birth, smoking status, alcohol consumption, and family history of cancer.

CONCLUSIONS

Our study suggests that infection by E. granulosus may increase cancer risk. If this observation can be confirmed independently, further investigation of the mechanisms underlying the association is warranted.