sCD155 as a potential marker for diagnosing the vascular invasion in hepatic alveolar echinococcosis.

BACKGROUND: Alveolar Echinococcosis (AE) is a malignant zoonotic disease caused by Echinococcus multilocularis infection. Considering whether the lesion is accompanied by vascular invasion (VI) is crucial for treatment strategies. A cost-effective and convenient clinical diagnostic method is urgently needed to supplement current techniques. Consequently, we detected soluble CD155 (sCD155) as a potential biomarker for diagnosing VI in hepatic alveolar echinococcosis (HAE). METHODS: Blood samples were from 42 AE patients and 49 healthy controls (HCs). Based on the computed tomography (CT) and contrast-enhanced CT, AE patients were further categorized into HAE with VI (VIAE; 27 cases) and HAE without VI (NVAE; 15 cases). The sCD155 concentration was measured by an enzyme-linked immunosorbent assay (ELISA). Correlations between sCD155 expression levels and clinicopathological features of AE patients were analyzed using SPSS and GraphPad Prism software. RESULTS: The sCD155 concentrations in AE patients were significantly higher than in HCs. The serum sCD155 level significantly differed between the VIAE and NVAE groups. The univariate analysis showed that VI of AE was significantly correlated with the sCD155 level when the sCD155 was greater than 11 ng/mL. After adjusting for potential confounding factors, the multivariable analysis showed that sCD155 had an independent effect on VI of HAE. The receiver operating characteristic (ROC) curve showed that sCD155 could differentially diagnose VI of HAE at the cut-off value of 11.08 ng/mL with an area under the curve (AUC) value of 0.75. The sensitivity and specificity were 74.07 % and 66.67 %, respectively; the positive and negative predictive values were 74.07 % and 60.00 %, respectively. CONCLUSION: The sCD155 could be a VI biomarker for HAE. Elevated sCD155 levels are indicative of an increased likelihood of concomitant VI in HAE patients, necessitating a thorough evaluation of vascular impairment and the formulation of individualized management strategies.

Inhibition of AMPK activation in Echinococcus granulosus sensu stricto limits the parasite's glucose metabolism and survival.

Cystic echinococcosis (CE) is a zoonotic parasitic disease caused by larvae of the Echinococcus granulosus sensu lato (s.l.) cluster. There is an urgent need to develop new drug targets and drug molecules to treat CE. Adenosine monophosphate (AMP)-activated protein kinase (AMPK), a serine/threonine protein kinase consisting of α, ß, and γ subunits, plays a key role in the regulation of energy metabolism. However, the role of AMPK in regulating glucose metabolism in E. granulosus s.l. and its effects on parasite viability is unknown. In this study, we found that targeted knockdown of EgAMPKα or a small-molecule AMPK inhibitor inhibited the viability of E. granulosus sensu stricto (s.s.) and disrupted the ultrastructure. The results of in vivo experiments showed that the AMPK inhibitor had a significant therapeutic effect on E. granulosus s.s.-infected mice and resulted in the loss of cellular structures of the germinal layer. In addition, the inhibition of the EgAMPK/EgGLUT1 pathway limited glucose uptake and glucose metabolism functions in E. granulosus s.s.. Overall, our results suggest that EgAMPK can be a potential drug target for CE and that inhibition of EgAMPK activation is an effective strategy for the treatment of disease.

Adipose-Derived Mesenchymal Stem Cell Facilitate Hematopoietic Stem Cell Proliferation via the Jagged-1/Notch-1/Hes Signaling Pathway.

Background: Poor graft function (PGF) is a life-threatening complication following hematopoietic stem cell transplantation (HSCT). Current therapies, such as CD34+ cell infusion, have shown limited effectiveness. Conversely, mesenchymal stem cells (MSCs) show potential in addressing PGF. Adipose-derived mesenchymal stem cells (ADSCs) effectively support long-term hematopoietic stem cell proliferation. Therefore, this study aimed to investigate the mechanisms underlying the long-term hematopoietic support provided by ADSCs. Methods: ADSCs were isolated from mice and subsequently identified. In vitro experiments involved coculturing ADSCs as feeders with Lin-Sca-1+c-kit+ (LSK) cells from mice for 2 and 5 weeks. The number of LSK cells was quantified after coculture. Scanning electron microscopy was utilized to observe the interaction between ADSCs and LSK cells. Hes-1 expression was assessed using western blot and real-time quantitative PCR. An γ-secretase inhibitor (GSI) was used to confirm the involvement of the Jagged-1/Notch-1/Hes-1 pathway in LSK cell expansion. Additionally, Jagged-1 was knocked down in ADSCs to demonstrate its significance in ADSC-mediated hematopoietic support. In vivo experiments were conducted to study the hematopoietic support provided by ADSCs through the infusion of LSK, LSK + fibroblasts, and LSK + ADSCs, respectively. Mouse survival, platelet count, leukocyte count, and hemoglobin levels were monitored. Results: ADSCs showed high-Jagged-1 expression and promoted LSK cell proliferation. There was a direct interaction between ADSCs and LSK cells. After coculture, Hes-1 expression increased in LSK cells. Moreover, GSI-reduced LSK cell proliferation and Hes-1 expression. Knockdown of Jagged-1 attenuated ADSCs-mediated promotion of LSK cell proliferation. Furthermore, ADSCs facilitated hematopoietic recovery and promoted the survival of NOD/SCID mice. Conclusion: The hematopoietic support provided by ADSCs both in vivo and in vitro may be mediated, at least in part, through the Jagged-1/Notch-1 signaling pathway. These findings provide valuable insights into the mechanisms underlying ADSCs-mediated hematopoietic support and may have implications for improving the treatment of PGF following HSCT.

Cytokine-induced apoptosis inhibitor 1: a comprehensive analysis of potential diagnostic, prognosis, and immune biomarkers in invasive breast cancer.

Background: Cytokine-induced apoptosis inhibitor 1 (CIAPIN1) is strictly associated with the incidence and progress of several malignant tumors, but its effect on invasive breast cancer (IBC) remains unclear. We directed to research the potential diagnostic and prognostic significance of CIAPIN1 in IBC. Methods: The Cancer Genome Atlas (TCGA) database and Tumor Immune Estimation Resource (TIMER) database were utilized to examine CIAPIN1 expression level in IBC and its relationship with clinicopathological features. The diagnostic value and prognostic importance of CIAPIN1 in IBC were assessed by Kaplan-Meier analysis, Cox regression analysis, receiver operating characteristic (ROC) curve and nomogram model. The STRING database and enrichment analysis were utilized to discover the interacting proteins, biological roles and possible cellular mechanisms related to CIAPIN1. The methylation status of CIAPIN1 was analyzed using MethSurv database and the University of Alabama at Birmingham Cancer Data Analysis Portal (UALCAN). By using Spearman correlation assessment, how the expression of CIAPIN1 was related to TP53, immune checkpoint genes and immune cell infiltration was determined. Results: CIAPIN1 mRNA and protein levels were overexpressed in IBC, and significantly correlated with T stage, histological type, age, ER status, PR status and PAM50 (P<0.001). CIAPIN1 overexpression significantly decreased overall survival, distant metastasis free survival (DMFS) and relapse free survival in IBC patients (P<0.001). Similarly, hypermethylation of CIAPIN1 was associated with adverse outcomes in IBC patients. Multivariate Cox analysis identified CIAPIN1 as a potential risk factor for disease specific survival (DSS) and progression free survival (PFS) in individuals with IBC. The outcomes of the ROC curve showed that CIAPIN1 had a better accuracy in predicting ER(-), PR(-) and Asian breast cancer subtypes. Furthermore, there was a substantial correlation between the CIAPIN1 expression level in IBC and immune cell infiltration, TP53, and immune checkpoint genes. Conclusions: The high expression of CIAPIN1 in IBC is significantly related to the infiltration status of various tumor immune cells and the poor prognosis of IBC patients. According to this current study, CIAPIN1 is a promising diagnostic and prognostic marker for IBC.

Gelsolin: A comprehensive pan-cancer analysis of potential prognosis, diagnostic, and immune biomarkers.

Introduction: Gelsolin (GSN), a calcium-regulated actin-binding protein, is out of balance in various cancers. It can mediate cytoskeletal remodeling and regulate epithelial-mesenchymal conversion (EMT), but the studies on GSN function in pan-cancer are limited. Methods: We studied the transcription level, prognostic impact, diagnostic value, genetic, epigenetic modification, methylation level and immune significance of GSN in pan-cancer to fully comprehend the function of GSN in various malignancies based on multiple databases like The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO). Results: Pan-cancer research showed that GSN was downregulated in most tumors and expressed differently in immunological and molecular subtypes of many cancers. GSN had varying impacts on the prognosis of various tumor types. However, all had moderate to high diagnostic efficiency, and serum GSN had good diagnostic value in breast cancer patients (AUC = 0.947). Moreover, GSN was a distinguishing prognosis factor for some specific cancer types. The GSN protein was hypophosphorylated, and its promoter was hypermethylated in most cancers. GSN was linked to the infiltration level of several immunity cells and was essential in anti-tumor immune cell infiltration. KEGG and GSEA analyses showed that GSN was vital in the functions and proteoglycans processes in cancer, chemokine signaling pathway and other immune-related pathways, DNA methylation and cell cycle. Discussion: In conclusion, GSN possesses the ability to be a predictive, diagnostic, and immune indicator in pan-cancer.

TIGIT as a Novel Prognostic Marker for Immune Infiltration in Invasive Breast Cancer.

BACKGROUND: To assess the levels and potential therapeutic and prognostic significance of TIGIT in invasive breast cancer. METHODS: The Cancer Genome Atlas database was used to evaluate TIGIT levels in invasive breast cancer and its association with clinicopathological features. Immunohistochemistry (IHC) was performed to validate it. Further, the Kaplan-Meier survival curve, univariate and multivariate Cox regression models were applied in analyzing the role of TIGIT in the prognosis of invasive breast cancer. Go / KEGG enrichment analyses techniques were used to investigate the possible cellular mechanism, and string database was used to explore TIGIT-related proteins. Finally, the TIMER database was used to determine the association between TIGIT and immune cell infiltrations. RESULTS: TIGIT was differentially expressed in Pan cancer tissues compared with normal tissues. Relative to normal tissues, TIGIT levels in invasive breast cancer were elevated (p<0.05). TIGIT mRNA level was significantly different from T stage, age, ER and PR level (p<0.05). The high levels of TIGIT exhibited positive correlations with PFI and OS (p<0.05). Univariate analysis revealed that age, clinical stage, high TNM stage, menopausal status and radiotherapy were the factors affecting OS (p< 0.05). Multivariate analysis revealed that age, high clinical stage and menopausal status were independent risk factors for tumor progression (p<0.05). CD226, INPP5D, PVR, PVRL2 and PVRL3 proteins interact with TIGIT. The TIGIT levels were significantly correlated with infiltrations of immune cells (such as CD8+ T cells) (r=0.917, p<0.05). CONCLUSION: TIGIT is elevated in invasive breast tumor and is closely associated with the prognosis of invasive breast cancer. TIGIT may be the target of immunotherapy for invasive breast cancer.

Upregulated TUBG1 expression is correlated with poor prognosis in hepatocellular carcinoma.

Background: Hepatocellular carcinoma (HCC) development is a complex pathological process. Tubulin gamma 1 (TUBG1) plays an oncogenic role in several human cancers; however, its functional role in HCC tumorigenesis remains unknown. Methods: Herein we first evaluated the gene expression levels of TUBG1 in HCC using data from The Cancer Genome Atlas and Gene Expression Profiling Interactive Analysis databases. We then elucidated the association between TUBG1 gene expression levels and survival rates of patients with HCC. Cell cycle, proliferation, transwell migration, and matrigel invasion assays were used to study the effects of TUBG1 on the malignant phenotypes of HCC cells. Results: Based on the data obtained from the aforementioned databases and our in vitro experiments, TUBG1 was found to be overexpressed in HCC and patients with high TUBG1 expression levels showed a remarkably poor overall survival rate. In addition, the expression of TUBG1 significantly promoted the malignant phenotypes of HCC cells in vitro. Gene ontology term enrichment analysis revealed that co-regulated genes were enriched in biological processes mainly involved in chromosome segregation, chromosomal region, and chromatin binding; moreover, Kyoto Encyclopedia of Genes and Genome pathway analysis showed that they were mainly involved in cell cycle, oocyte meiosis, platinum drug resistance, and the p53 signaling pathway. Conclusions: We report that TUBG1 is an important oncogene in HCC. It promotes HCC progression and may serve as a potential prognostic biomarker for HCC. Future studies are warranted to unveil molecular biological mechanisms underlying TUBG1 carcinogenesis.

In vitro efficacy of Capparis spinosa extraction against larvae viability of Echinococcus granulosus sensu stricto.

Cystic echinococcosis (CE) is a chronic zoonotic parasitic disease caused by infection with the larvae of the Echinococcus granulosus sensu lato (s.l.) cluster. Currently, new drugs are urgently required due to the poor therapeutic effect of the existing drugs albendazole and mebendazole. Capparis spinosa, a traditional medicinal plant, has potential therapeutic effects on various diseases based on extracts from its fruit and other parts. The results of this study demonstrated that the water-soluble and ethanolic extracts of C. spinosa fruit had in vitro killing effects on the larvae of E. granulosus sensu stricto (s.s.) and disrupted the ultrastructure of protoscoleces and metacestodes. In vitro cytotoxicity assays showed that the water-soluble and ethanolic extracts of C. spinosa fruit were not significantly toxic to primary mouse hepatocytes at an effective dose to CE. In conclusion, water-soluble and ethanolic extracts of C. spinosa fruit have great potential for the development of new drugs for the treatment of CE.

Transplantation of adipose-derived stem cells ameliorates Echinococcus multilocularis-induced liver fibrosis in mice.

BACKGROUND: Alveolar echinococcosis (AE) can cause severe liver fibrosis and could be fatal if left untreated. Currently, there are no effective therapeutic options for AE-induced liver fibrosis. In view of the therapeutic potential of adipose-derived stem cells (ADSCs), we investigated whether ADSCs transplantation has the ability to control or reverse fibrosis progression in the liver of Echinococcus multilocularis (E. multilocularis) infected mice. METHODOLOGY/PRINCIPAL FINDINGS: C57BL/6 mice infected with E. multilocularis through portal vein inoculation were intravenously injected with ADSCs isolated from inguinal adipose tissues of 6-8 weeks old mice. Histopathological analysis including heamatoxylin & eosin staining as well as Masson's trichrome staining, and Sirius red staining were performed to access the degree of liver fibrosis. Histopathological examination 30 days after ADSCs transplantation revealed that ADSCs significantly decreased the degree of liver fibrosis in E. multilocularis infected mice by inhibiting the expressions of α-SMA and type 1 collagen deposition. In addition, compared to the non-transplanted group, ADSCs transplantation reduced fibrotic areas in E. multilocularis infected mice. We also found that ADSCs transplantation significantly down-regulated TGF-ß1 and TGF-ßR expressions, while up-regulating Smad7 expression in the TGF-ß/Smad signaling pathway. CONCLUSIONS: ADSCs can alleviate Echinococcus multilocularis infection-induced liver fibrosis by modulating the activity level of the TGF-ß/Smad7 signaling pathway and provide a potential therapeutic approach for E. multilocularis-induced fibrosis.

Serum platelet-derived growth factor-BB levels as a potential biomarker in assessing the metabolic activity of lesions in alveolar echinococcosis patients.

BACKGROUND: Alveolar echinococcosis (AE) is a chronic disease caused by the larval stage of Echinococcus multilocularis. Assessing the metabolic activity of AE lesions is critical to evaluate disease progression and survey treatment options. There is an urgent need to identify more rapid, convenient, and non-invasive clinical detection methods to substitute the current techniques. Herein, we evaluated the viability of platelet-derived growth factor-BB (PDGF-BB) as a biomarker for detecting the metabolic activity of AE patients and their correlations with clinicopathological features of AE patients. METHODS: Sera were collected from 28 AE patients and a homogenous cohort of 28 healthy individuals. The concentration of serum PDGF-BB homodimers (sPDGF-BB) was assessed via an enzyme-linked immunosorbent assay (ELISA). Liver tissue samples were obtained from a consecutive series of 28 AE patients who underwent surgical resection. Thereafter, we determined the expression levels of local PDGF-BB and platelet-derived growth factor receptor-ß (PDGFR-ß) through immunohistochemistry (IHC). Correlations of PDGF-BB expression levels with clinicopathological features of AE patients were analyzed using SPSS. RESULTS: The concentrations of sPDGF-BB were significantly lower in AE patients (p < 0.0001), particularly in High Metabolically Active AE patients (HMAE) patients (p < 0.05). The expression levels of PDGF-BB and its receptor were both significantly higher in close liver tissue (CLT) in AE patients (p < 0.0001). We also found that metabolically active AE and sPDGF-BB are significantly negatively correlated (r = -0.624, p = 0.0004). Beside, the local expression levels of PDGF-BB was positively correlated with metabolic activity, PNM stage, and lesion size. Notably, the sPDGF-BB levels were proposed as a potential biomarker for assessing metabolic activity of AE, with 81.0% sensitivity and 85.7% specificity (95% confidence interval, p = 0.003). CONCLUSIONS: Serum levels of PDGF-BB could be a simple, non-invasive, and quick biomarker for assessing the metabolic activity of lesions in AE patients.

EgGLUT1 Is Crucial for the Viability of Echinococcus granulosus sensu stricto Metacestode: A New Therapeutic Target?

Cystic echinococcosis (CE) is a zoonotic parasitic disease caused by infection with the larvae of Echinococcus granulosus sensu lato (s.l.) cluster. It is urgent to identify novel drug targets and develop new drug candidates against CE. Glucose transporter 1 (GLUT1) is mainly responsible for the transmembrane transport of glucose to maintain its constant cellular availability and is a recent research hotspot as a drug target in various diseases. However, the role of GLUT1 in E. granulosus s.l. (EgGLUT1) was unknown. In this study, we cloned a conserved GLUT1 homology gene (named EgGLUT1-ss) from E. granulosus sensu stricto (s.s.) and found EgGLUT1-ss was crucial for glucose uptake and viability by the protoscoleces of E. granulosus s.s. WZB117, a GLUT1 inhibitor, inhibited glucose uptake by E. granulosus s.s. and the viability of the metacestode in vitro. In addition, WZB117 showed significant therapeutic activity in E. granulosus s.s.-infected mice: a 10 mg/kg dose of WZB117 significantly reduced the number and weight of parasite cysts (P < 0.05) as efficiently as the reference drug, albendazole. Our results demonstrate that EgGLUT1-ss is crucial for glucose uptake by the protoscoleces of E. granulosus s.s., and its inhibitor WZB117 has a therapeutic effect on CE.

Corrigendum: Upregulated LINC01667 Expression Is Correlated With Poor Prognosis in Hepatocellular Carcinoma.

[This corrects the article DOI: 10.3389/fonc.2021.650173.].

An improved experimental method for simultaneously isolating hepatocytes and hepatic stellate cells in mouse liver infected with Echinococcus multilocularis.

BACKGROUND: Alveolar echinococcosis (AE) is a zoonotic disease caused by the larval stage of Echinococcus multilocularis parasitizing in the human liver, causing local pathological changes in the liver and manifesting as hyperplasia, liver fibrosis, atrophy, degeneration, and necrosis. Here, we report a method that can simultaneously isolate hepatocytes and hepatic stellate cells (HSCs) from mice infected with Echinococcus multilocularis. METHODS: A mouse model of AE was established. Hepatocytes and HSCs were isolated from mouse liver using a two-step method combining in situ collagenase perfusion and gradient centrifugation. Expressions of Alb, Desmin, and α-SMA were detected with immunofluorescence to identify the isolated hepatocytes and HSCs. RESULTS: The viability and purity of hepatocytes and HSCs both reached 90% or above. For hepatocytes, clear cell boundaries were observed, and the nuclei were round or oval, with clear nucleoli. There was a homogeneous distribution of the hepatocyte marker Alb in the cytoplasm of hepatocytes. Lipid droplets and Desmin expression were observed in the cytoplasm of freshly isolated HSCs. During the activation of HSCs, the lipid droplets gradually decreased and disappeared with a high expression of α-SMA. CONCLUSION: Hepatocytes and HSCs are simultaneously isolated. This may provide a research tool to investigate the interaction between hepatocytes and HSCs and to investigate the mechanism of Echinococcus multilocularis infection-induced liver pathological changes.

Upregulated LINC01667 Expression Is Correlated With Poor Prognosis in Hepatocellular Carcinoma.

The development of hepatocellular carcinoma (HCC) is a complex pathological process. Long intergenic non-protein-coding RNA 1667 (LINC01667, also known as MGC38584) plays an oncogenic role in several human cancers; however, its functional role in HCC tumorigenesis remains unknown. Here, we first evaluated the gene expression levels of LINC01667 in HCC using data from The Cancer Genome Atlas and Gene Expression Profiling Interactive Analysis (GEPIA) databases. We then elucidated the association between LINC01667 gene expression levels and the survival rates of patients with HCC. We detected the effect of LINC01667 on the malignant phenotypes (cell proliferation, migration, invasion and apoptosis etc.) and the MAPK and PI3K/AKT/mTOR signaling pathways of HepG2, SMMC-7721 and HUH7 cells. We also analyzed the sensitivity of HepG2, SMMC-7721 and HUH7 with different expression levels of LINC01667 to anti-HCC drugs in vitro. Based on data from the aforementioned databases and our experiments in vitro, we found that LINC01667 was overexpressed in HCC, and that patients with high LINC01667 levels had a remarkably poor overall survival rate. In addition, inhibition of LINC01667 expression suppressed the proliferation, migration and invasion of HepG2 and SMMC-7721 cells and promoted their apoptosis in vitro. In contrast, overexpression of LINC01667 promoted the proliferation, migration and invasion of HUH7 cells and suppressed their apoptosis in vitro. ChIRP-seq (chromatin isolation by RNA purification) showed that LINC01667 bound to MEG3, and downregulated the expression of MEG3. In addition, western blotting showed that LINC01667 could activate the NF-κB pathway to promote cancer progression. In conclusion, we report that LINC01667 is an important oncogene in HCC and may be used as a potential diagnostic and prognostic biomarker of HCC.

Adipose tissue-derived stem cells modulate immune function in vivo and promote long-term hematopoiesis in vitro using the aGVHD model.

The present study was designed to investigate the effect of adipose-derived stem cells (ADSCs) on acute graft vs. host disease (aGVHD) and hematopoietic recovery after allogeneic hematopoietic stem cell transplantation. ADSCs, bone marrow-derived stem cells (BMSCs) and fibroblasts were cultured. ADSCs were cocultured with hematopoietic stem/progenitor cells. Then, ADSCs were infused into the aGVHD rat model. The survival of the rats was recorded. Livers and small intestines were obtained from sacrificed rats for pathological examinations. Expression of the Sry gene in recipient rats that survived longer than 21 days was examined by real-time PCR to detect the presence of donor Y chromosome. Expression of serum interferon (INF)-γ and interleukin (IL)-4 was detected by ELISA at 0, 7, 14, 21 and 50 days after transplantation. Transplantation of ADSCs improved the survival of aGVHD rats. Survived ADSCs participated in hematopoietic reconstitution in aGVHD rats. ADSCs decreased aGVHD severity by immunomodulation. ADSCs support the proliferation of hematopoietic stem/progenitor cells in vitro. The present study demonstrated that ADSCs may reduce aGVHD by influencing the balance of IL-4 and INF-γ and can promote long-term hematopoiesis.

Dual Role of Hepatic Macrophages in the Establishment of the Echinococcus multilocularis Metacestode in Mice.

Echinococcus multilocularis larvae, predominantly located in the liver, cause a tumor-like parasitic disease, alveolar echinococcosis (AE), that is characterized by increased infiltration of various immune cells, including macrophages, around the lesion that produces an "immunosuppressive" microenvironment, favoring its persistent infection. However, the role of hepatic macrophages in the host defense against E. multilocularis infection remains poorly defined. Using human liver tissues from patients with AE and a hepatic experimental mouse model of E. multilocularis, we investigated the phenotype and function of hepatic macrophages during the parasite infection. In the present study, we found that a large number of CD68+ macrophages accumulated around the metacestode lesion in the liver of human AE samples and that both S100A9+ proinflammatory (M1 phenotype) and CD163+ anti-inflammatory (M2 phenotype) macrophages were significantly higher in close liver tissue (CLT) than in distant liver tissue (DLT), whereas M2 macrophages represent the dominant macrophage population. Furthermore, E. multilocularis-infected mice exhibited a massive increase in macrophage (F4/80+) infiltration in the liver as early as day 5, and the infiltrated macrophages were mainly monocyte-derived macrophages (CD11bhi F4/80int MoMFs) that preferentially differentiated into the M1 phenotype (iNOS+) at the early stage of E. multilocularis infection and then polarized to anti-inflammatory macrophages of the M2 phenotype (CD206+) at the chronic stage of infection. We further showed that elimination of macrophages by treatment of mice with clodronate-liposomes before E. multilocularis infection impaired worm expulsion and was accompanied by a reduction in liver fibrosis, yielding a high parasite burden. These results suggest that hepatic macrophages may play a dual role in the establishment and development of E. multilocularis metacestodes in which early larvae clearance is promoted by M1 macrophages while persistent metacestode infection is favored by M2 macrophages.

Immune Exhaustion of T Cells in Alveolar Echinococcosis Patients and Its Reversal by Blocking Checkpoint Receptor TIGIT in a Murine Model.

BACKGROUND AND AIMS: The cestode Echinococcus multilocularis infection, a serious health problem worldwide, causes alveolar echinococcosis (AE), a tumor-like disease predominantly located in the liver and able to spread to any organs. Until now, there have been few studies that explore how T-cell exhaustion contributes to the parasite's escape from immune attack and how it might be reversed. APPROACH AND RESULTS: In this study, we found that liver T-cell immunoreceptor with immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domain (TIGIT) expression was significantly enhanced and positively correlated with lesion activity in AE patients. High TIGIT expression in both liver-infiltrating and blood T cells was associated with their functional exhaustion, and its ligand CD155 was highly expressed by hepatocytes surrounding the infiltrating lymphocytes. In co-culture experiments using human blood T cells and hepatic cell line HL-7702, CD155 induced functional impairment of TIGIT+ T cells, and in vitro blockade with TIGIT antibody restored the function of AE patients' T cells. Similar TIGIT-related functional exhaustion of hepatic T cells and an abundant CD155 expression on hepatocytes were observed in E. multilocularis-infected mice. Importantly, in vivo blocking TIGIT prevented T-cell exhaustion and inhibited disease progression in E. multilocularis-infected mice. Mechanistically, CD4+ T cells were totally and CD8+ T cells partially required for anti-TIGIT-induced regression of parasite growth in mice. CONCLUSIONS: This study demonstrates that E. multilocularis can induce T-cell exhaustion through inhibitory receptor TIGIT, and that blocking this checkpoint may reverse the functional impairment of T cells and represent a possible approach to immunotherapy against AE.

The local immune response during Echinococcus granulosus growth in a quantitative hepatic experimental model.

The local immune mechanisms responsible for the establishment and development of Echinococcus granulosus sensu stricto infection in the liver, have been little explored. We developed a suitable experimental model that mimics naturally infected livers using portal injection of protoscoleces. Opposite to Echinococcus multilocularis infection which is dose-dependent, fully mature hydatid cysts can be established in the liver whatever the injection dose; although most of the infection sites were seen at the establishment phase as inflammatory granulomas associated with fibrosis, they never matured into cysts. At the establishment phase, a strong immune response was composed of T and B cells, with T1-type, T2-type cells and cytokines and IL-10-secreting CD8+ T cells in the liver. At the established phase, results suggested a local production of antibodies by B cells, and an involvement of NK and NKT cells. Infection outcome and local immune response in the liver, were different in the mouse models of Echinococcus granulosus sensu stricto and Echinococcus multilocularis respectively; however, only early specificities at the microenvironment level might explain the major differences found between the lesions induced by the two species. Our quantitative experimental model appears fully appropriate to further study this microenvironment and its relationship with each cestode species.

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.

Roles of SP600125 in expression of JNK, RANKL and OPG in cultured dental follicle cells.

OBJECTIVE: To investigate the expression of C-JNK, RANKL and OPG after SP600125 administration in cultured dental follicle cells (DFCs). METHODS: TRAP staining and electron microscope were carried out on day 7 and 9 after coculture of BMMs and DFCs with a ratio of 5:1 in different groups. To determine the effects of SP600125 on the expression of C-JNK, RANKL and OPG mRNA and protein, cultured DFCs were divided into control group, DMSO group and SP600125 groups. Real-time PCR and Western blot analysis were performed to investigate the expression of the mRNA and protein, respectively. RESULTS: TRAP assay indicated that the number of multinucleated osteoclasts in the SP600125 group showed significant decrease compared with that of control (P < 0.05). The expression of JNK protein in the SP600125 groups showed significant decline compared with that of the control group and blank control (P < 0.05). Significant decrease was noticed in the RANKL protein expression with the elevation of SP600125. CONCLUSIONS: SP600125 could inhibit the formation of osteoclast in the coculture system of DFCs and BMMs. After SP600125 treatment, the expression of RANKL and JNK showed a trend of decrease, and the expression of OPG showed gradual increase followed by gradual decrease.