Itaconate inhibits CD103 + T RM cells and alleviates hepatobiliary injury in mouse models of primary sclerosing cholangitis.

BACKGROUND AND AIMS: Primary sclerosing cholangitis (PSC) is a chronic progressive liver disease characterized by the infiltration of intrahepatic tissue-resident memory CD8 + T cells (T RM ). Itaconate has demonstrated therapeutic potential in modulating inflammation. An unmet need for PSC is the reduction of biliary inflammation, and we hypothesized that itaconate may directly modulate pathogenic T RM . APPROACH AND RESULTS: The numbers of intrahepatic CD103 + T RM were evaluated by immunofluorescence in PSC (n = 32), and the serum levels of itaconate in PSC (n = 64), primary biliary cholangitis (PBC) (n = 60), autoimmune hepatitis (AIH) (n = 49), and healthy controls (n = 109) were determined by LC-MS/MS. In addition, the frequencies and immunophenotypes of intrahepatic T RM using explants from PSC (n = 5) and healthy donors (n = 6) were quantitated by flow cytometry. The immunomodulatory properties of 4-octyl itaconate (4-OI, a cell-permeable itaconate derivative) on CD103 + T RM were studied in vitro. Finally, the therapeutic potential of itaconate was studied by the administration of 4-OI and deficiency of immune-responsive gene 1 (encodes the aconitate decarboxylase producing itaconate) in murine models of PSC. Intrahepatic CD103 + T RM was significantly expanded in PSC and was positively correlated with disease severity. Serum itaconate levels decreased in PSC. Importantly, 4-OI inhibited the induction and effector functions of CD103 + T RM in vitro. Mechanistically, 4-OI blocked DNA demethylation of RUNX3 in CD8 + T cells. Moreover, 4-OI reduced intrahepatic CD103 + T RM and ameliorated liver injury in murine models of PSC. CONCLUSIONS: Itaconate exerted immunomodulatory activity on CD103 + T RM in both in vitro and murine PSC models. Our study suggests that targeting pathogenic CD103 + T RM with itaconate has therapeutic potential in PSC.

P4HA2 induces hepatic ductular reaction and biliary fibrosis in chronic cholestatic liver diseases.

BACKGROUNDS: Prolyl-4-hydroxylases (P4Hs) are key enzymes in collagen synthesis. The P4HA subunit (P4HA1, P4HA2, and P4HA3) contains a substrate binding and catalyzation domain. We postulated that P4HA2 would play a key role in the cholangiocyte pathology of cholestatic liver diseases. METHODS: We studied humans with primary biliary cholangitis (PBC) and Primary sclerosing cholangitis (PSC), P4HA2 -/- mice injured by DDC, and P4HA2 -/- /MDR2 -/- double knockout mice. A parallel study was performed in patients with PBC, PSC, and controls using immunohistochemistry and immunofluorescence. In the murine model, the level of ductular reaction and biliary fibrosis were monitored by histology, qPCR, immunohistochemistry, and Western blotting. Expression of Yes1 Associated Transcriptional Regulator (YAP) phosphorylation was measured in isolated mouse cholangiocytes. The mechanism of P4HA2 was explored in RBE and 293T cell lines by using qPCR, Western blot, immunofluorescence, and co-immunoprecipitation. RESULTS: The hepatic expression level of P4HA2 was highly elevated in patients with PBC or PSC. Ductular reactive cholangiocytes predominantly expressed P4HA2. Cholestatic patients with more severe liver injury correlated with levels of P4HA2 in the liver. In P4HA2 -/- mice, there was a significantly reduced level of ductular reaction and fibrosis compared with controls in the DDC-induced chronic cholestasis. Decreased liver fibrosis and ductular reaction were observed in P4HA2 -/- /MDR2 -/- mice compared with MDR2 -/- mice. Cholangiocytes isolated from P4HA2 -/- /MDR2 -/- mice displayed a higher level of YAP phosphorylation, resulting in cholangiocytes proliferation inhibition. In vitro studies showed that P4HA2 promotes RBE cell proliferation by inducing SAV1 degradation, eventually resulting in the activation of YAP. CONCLUSIONS: P4HA2 promotes hepatic ductular reaction and biliary fibrosis by regulating the SAV1-mediated Hippo signaling pathway. P4HA2 is a potential therapeutic target for PBC and PSC.

Suppression of YTHDF2 attenuates autoimmune hepatitis by expansion of myeloid-derived suppressor cells.

BACKGROUND & AIMS: The N6-methyladenosine (m6A) reader YTH domain-containing family protein 2 (YTHDF2) is critically involved in a multiplicity of biological processes by mediating the degradation of m6A modified mRNAs. Based on our current understanding of this process, we hypothesized that YTHDF2 will play a role in the natural history and function of myeloid-derived suppressor cells (MDSC) and in particular in AIH. APPROACH & RESULTS: We took advantage of YTHDF2 conditional knock-out mice to first address the phenotype and function of MDSCs by flow cytometry. Importantly, the loss of YTHDF2 resulted in a gradual elevation of MDSCs including PMN-MDSCs both in liver and ultimately in the BM. Notably, YTHDF2 deficiency in myeloid cells attenuated concanavalin (ConA)-induced liver injury, with enhanced expansion and chemotaxis to liver. Furthermore, MDSCs from Ythdf2CKO mice had a greater suppressive ability to inhibit the proliferation of T cells. Using multi-omic analysis of m6A RNA immunoprecipitation (RIP) and mRNA sequencing, we noted RXRα as potential target of YTHDF2. Indeed YTHDF2-RIP-qPCR confirmed that YTHDF2 directly binds RXRα mRNA thus promoting degradation and decreasing gene expression. Finally, by IHC and immunofluorescence, YTHDF2 expression was significantly upregulated in the liver of patients with AIH which correlated with the degree of inflammation. CONCLUSION: Suppression of YTHDF2 enhances the expansion, chemotaxis and suppressive function of MDSCs and our data reveals a unique therapeutical target in immune mediated hepatitis.

Application of metabolomics to explore the automatic oxidation process of hazelnut oil.

The oxidation metabolites of hazelnut oil are complex and vary with different degrees of oxidation. At present, few studies have investigated the change law of metabolites during the oxidation process of hazelnut oil. In this study, ultrahigh-performance liquid chromatography tandem Q-Exactive high-resolution mass spectrometry (UPLC-QE/MS) was used to analyze the differential metabolites resulting from the oxidation of cold-pressed hazelnut oil during storage for 40 days with accelerated oxidation. The oxidation level of cold-pressed hazelnut oil was evaluated by monitoring the free radical relative strength during accelerated oxidation. A total of 1010 metabolites in 12 super classes were detected in fresh hazelnut oil. Based on multivariate statistical analysis of all metabolites and the change law of free radicals in hazelnut oil, it was found that hazelnut oil enters the deep oxidation stage after accelerated oxidation for 30 days. A statistical analysis of differential metabolites and metabolic pathways was also carried out. The metabolite map obtained in this study can further distinguish hazelnut oil with different degrees of oxidation. Bioinformatics analysis indicated that linoleic acid metabolism and sphingolipid (SP) metabolism are the most important metabolic pathways in the entire oxidation process. These results provide a basis for better understanding the composition of hazelnut oil metabolites with different oxidation levels, identifying markers for oxidation level evaluation and analyzing the oxidative metabolism mechanism of hazelnut oil. This study provides new resources and new ideas for studying methods to prolong the shelf life of edible oils.

Characterization of intrahepatic B cells in acute-on-chronic liver failure.

Background and objectives: Acute on chronic liver failure (ACLF) is characterized by the immunologic dissonance during the prolonged pathogenic development. Both abnormal innate immune response and adaptive T-cell response have been reported in patients with ACLF; however, less is known regarding B cells in ACLF pathogenesis. Previous reports were only based on immunophenotyping of peripheral blood samples. Here, we aim to dissect liver-infiltrating B-cell subpopulation in ACLF. Methods: Paired liver perfusate and peripheral blood were freshly collected from healthy living donors and recipients during liver transplantation. Liver tissues were obtained from patients with ACLF, cirrhosis, and healthy controls. Flow cytometry was used to characterize the phenotypic and functional alterations in intrahepatic and circulating B-cell populations from ACLF, cirrhosis, and healthy controls. The expression of CD19+ and CD138+ on liver tissues was examined by immunohistochemistry staining. Results: In this study, we first deciphered the intrahepatic B cells subsets of patients with ACLF. We found that the ACLF liver harbored reduced fraction of naïve B cells and elevated percentage of CD27+CD21- activated memory B cells (AM), CD27-CD21- atypical memory B cells (atMBC), CD27+IgD-IgM+(IgM+ memory B cells), and CD27+CD38++ plasma cells than cirrhosis and healthy controls. Moreover, these B subpopulations demonstrated enhanced activation and altered effector functions. Specifically, the ACLF liver was abundant in atMBC expressing higher CD11c and lower CD80 molecule, which was significantly correlated to alanine aminotransferase and aspartate aminotransferase. In addition, we found that intrahepatic CD27+CD38++plasma cells were preferentially accumulated in ACLF, which expressed more CD273 (PD-L2) and secreted higher granzyme B and IL-10. Finally, the enriched hepatic plasma B cells were in positive association with disease severity indices including alkaline phosphatase and gamma-glutamyl transferase. Conclusions: In this pilot study, we showed an intrahepatic B-cell landscape shaped by the ACLF liver environment, which was distinct from paired circulating B-cell subsets. The phenotypic and functional perturbation in atMBC and plasma cells highlighted the unique properties of infiltrating B cells during ACLF progression, thereby denoting the potential of B-cell intervention in ACLF therapy.

Exploring the environmental properties and resource utilization of construction waste in Beijing-Tianjin-Hebei region.

Beijing-Tianjin-Hebei region is a capital economic circle for the future. Promoting the coordinated development of its population, economy, resources and environment is a major national strategy. And as towns and cities continue to expand, the volume of construction waste is gradually expanding, posing a major challenge to the sustainable development of the construction industry. In order to solve this problem, this paper used portable X-ray fluorescence spectrometry to realize the on-site rapid monitoring of heavy metals in construction waste, and the correlation analysis result was R2 = 0.9908. The visualization of enrichment factor evaluation results was realized through ArcGIS. The Beijing-Tianjin-Hebei region is mainly polluted by heavy metal elements Cr, Zn, Pb and Hg, showing regional pollution characteristics, and the results of mercury morphology analysis show that all are inorganic mercury pollution, and methylmercury is not detected, and the cause can be traced to heavy industrial production in Tangshan City, which is consistent with industrial ecology. The results of leaching toxicity and cation anion analysis showed that the construction waste in Beijing-Tianjin-Hebei region had environmental risks to the surrounding surface water and groundwater. The resource treatment and disposal path were determined by means of XRD, ternary phase diagram and oxide composition analysis to avoid secondary pollution. This study explores the environmental properties and resource utilization pathways of construction waste in the Beijing-Tianjin-Hebei region, laying the foundation for research work on construction waste in the development of national urban agglomerations, effectively solving regional environmental pollution problems and promoting the sustainable development of the construction industry.

Intrahepatic activated leukocyte cell adhesion molecule induces CD6highCD4+ T cell infiltration in autoimmune hepatitis.

Background and objectives: Autoimmune hepatitis (AIH) is characterized by the expansion and accumulation of pathogenic T cells in liver. Although CD6 and its ligand activated leukocyte cell adhesion molecule (ALCAM) are involved in the evolution of multiple inflammatory diseases, their roles in the pathogenesis of AIH remain unknown. Herein, we aimed to investigate ALCAM-CD6 axis in AIH development. Methods: Immunohistochemistry was performed to examine hepatic expression of CD6 and ALCAM. The concentration of serum ALCAM was evaluated by ELISA. The phenotypes of liver infiltrating T cells were determined by flow cytometry. Primary human CD4+ T cells were used for functional studies. Results: Our data showed that patients with AIH exhibited significantly higher expression of CD6 in the liver as compared to primary biliary cholangitis (PBC), chronic hepatitis B (CHB), non-alcoholic liver disease (NAFLD), and healthy controls (HC). In addition, hepatic CD6 expression was strongly correlated with disease severity of AIH. CD6 was mainly expressed on CD4+ T cells in the liver and intrahepatic CD6highCD4+ T cells demonstrated stronger proinflammatory response and proliferation features than CD6low counterparts in both AIH and HC. ALCAM, the ligand of CD6, was highly expressed in the hepatocytes of AIH and serum ALCAM was strongly associated with clinical indices of AIH. Interestingly, close spatial location between CD6+CD4+ T cells and ALCAM+ hepatocytes was observed. Finally, we found that CD6highCD4+ T cells showed enhanced capacity of trans-endothelial migration in vitro, which could be promoted by recombinant ALCAM. Conclusions: Our study found that ALCAM-CD6 axis was upregulated in the AIH liver, suggesting a potential target for alleviating AIH.

Serum Biomarkers for Autoimmune Hepatitis Type 1: the Case for CD48 and a Review of the Literature.

In autoimmune hepatitis (AIH), the persisting inflammation contributes to fibrosis progression, for which conventional biochemical markers manifest relatively unsatisfactory prediction. Herein, we assessed the value of serum CD48 (sCD48) as an indicator for inflammation and fibrosis in AIH type 1. The levels of sCD48 were detected first in an exploratory cohort using ELISA. In this cohort, compared with healthy controls (4.90 ng/mL, P < 0.0001), primary biliary cholangitis (7.32 ng/mL, P < 0.0001), and non-alcoholic fatty liver disease (7.76 ng/mL, P < 0.0001), sCD48 levels were elevated in AIH (12.81 ng/mL) and correlated with histological inflammation and fibrosis. Further using multivariate logistic regression analysis, sCD48 was identified as an independent predictor for both significant inflammation (G3-4) and advanced fibrosis (S3-4). Two predictive scores, based on sCD48, were constructed for diagnosing significant inflammation and advanced fibrosis (sCD48-AIH-SI and sCD48-AIH-AF, respectively). Using these data as a premise, predictive abilities were subsequently evaluated and verified in a validation cohort. In the exploratory cohort, the area under the receiver operating characteristic curve of sCD48 and sCD48-AIH-SI, for significant inflammation, were 0.748 and 0.813, respectively. Besides, during treatment follow-up, sCD48 levels gradually decreased from immunosuppression initiation to re-evaluation biopsy, in parallel with aspartate transaminase, total sera IgG, and fibrosis-4 score. For AIH patients in a re-evaluation biopsy cohort, sCD48 could predict significant fibrosis (S2-4). Further using immunohistochemistry, hepatic CD48 expression was elevated in AIH patients and decreased after treatment. In conclusion, sCD48 and sCD48-based predictive scores predict histological inflammation and fibrosis in AIH-1. Detecting sCD48 might help in the clinical management of AIH.

The immunological characteristics of TSPAN1 expressing B cells in autoimmune hepatitis.

Background and aims: Tetraspanin proteins are closely related to the functional changes of B cells, including antigen presentation, production of cytokines, and transduction. We aim to explore the potential role of Tetraspanin 1 (TSPAN1) in the biological activities of B cells in AIH. Methods and results: Herein, this study found that numbers of cells expressing TSPAN1 were significantly increased in AIH patients compared to PBC, chronic hepatitis B, and healthy control (P < 0.0001). Moreover, there was a positive correlation between numbers of TSPAN1+ cells and AIH disease severity (P < 0.0001). Immunofluorescence staining further confirmed that TSPAN1 was primarily expressed on CD19+ B cells. Flow-cytometric analysis showed that TSPAN1+ B cells secreted more inflammatory cytokines and expressed higher level of CD86 than TSPAN1- B cells. Furthermore, compared with TSAPN1- cells, the expression of CXCR3 on TSPAN1+ cells was also higher. Meanwhile, CXCL10, the ligand of CXCR3, was significantly elevated in the liver of AIH (P < 0.01) and had positive correlation with the quantities of TSPAN1 (P < 0.05). Interestingly, the numbers of TSPAN1+ B cells were decreased in AIH patients after immunosuppressive therapy. Conclusions: TSPAN1+ B cells in the liver may promote the progression of AIH via secreting cytokines and presenting antigens. The chemotactic movement of TSPAN1+ B cells toward the liver of AIH was possibly due to CXCR3 - CXCL10 interaction.

TiO2 Nanosheet-Redox Graphene Oxide/Sulphur Cathode for High-Performance Lithium-Sulphur Batteries.

Lithium-sulphur batteries are considered as some of the most potent secondary-battery systems. These batteries are expected to have extensive applications in fields requiring high-energy density. However, such applications are hindered by some serious intrinsic obstacles. Herein, TiO2 nanosheets-rGO/sulphur (TiO2 NS-rGO/S) composites were fabricated through a two-process hydrothermal method. TiO2 nanosheets served as active sites for polysulphide absorption, whereas rGO offered space for sulphur improvement and TiO2 NS-rGO/S composites. The TiO2 NS-rGO/S composite exhibited high discharge capacity of 1099 mAh·g-1 at 0.2 C rate and retained a capacity of 690 mAh·g-1 after 100 cycles, with high sulphur loading of 3 mg·cm-2. The high initial specific discharge capacity and improved cyclic stability were attributed to the synergistic effects of TiO2 nanosheets and rGO. These results indicated that the simple, low-cost and scalable method provides a novel perspective on practical utilisation of lithium-sulphur batteries.

Novel nano-particulated exopolysaccharide produced by Klebsiella sp. PHRC1.001.

In recent decades, microbial synthesis of polysaccharides with special functional properties has attracted increasing attention. This work reported a novel exopolysaccharide (EPS)-producing strain, Klebsiella sp. PHRC1.001 isolated from activated sludge. Physicochemical, rheological, emulsifying and toxicological properties of the obtained EPS were characterized. The EPS was mainly composed of d-glucose and l-arabinose, and was found to exist in aqueous solution in a nano-particulated form (∼50nm in diameter) with a strong tendency of aggregation. Rheological analysis showed that the EPS aqueous solution was a typical pseudoplastic fluid at higher concentration and could form weak gel upon alkaline treatment followed by neutralization. The EPS exhibited excellent emulsifying properties in stabilizing oil-in-water emulsions presumably by a Pickering mechanism owing to its nanoparticle structure. Acute toxicity test showed that 1.8g EPS per kg of body weight caused no toxic effect on mice. PHRC1.001 EPS has the potential to be a novel industrial polysaccharide.

High levels of activin A detected in preeclamptic placenta induce trophoblast cell apoptosis by promoting nodal signaling.

CONTEXT: The pregnancy-specific disorder preeclampsia is a major cause of maternal mortality and morbidity. Activin A has been suggested as a potential biomarker of the disease, but whether it plays a role in the pathology of preeclampsia or is just a manifestation of the disease is not fully understood. OBJECTIVE: The objective of the study was to examine the roles of Activin A on placental trophoblast cells under pathological conditions of preeclampsia. DESIGN: Placental and plasma productions of Activin A in healthy pregnant women and preeclamptic patients were compared by using clinical samples obtained from Peking University First Hospital during November 2005 to November 2007. The role of Activin A at pathological doses was investigated in human trophoblast cells. RESULTS: Plasma and placental productions of Activin A were significantly higher in preeclamptic patients when compared with normal pregnant subjects in a Chinese Han population. Treatment of trophoblast cells with high doses of Activin A resulted in a significant increase in cell apoptosis. This effect was blocked not only by silencing Activin A's receptor activin receptor-like kinase 4 but also by knockdown of Nodal's receptor ALK7. Important to note was that Activin A could significantly increase Nodal expression in trophoblast cells, and knockdown of Nodal resulted in evident blockage on Activin A-induced trophoblast cell apoptosis. CONCLUSION: High levels of Activin A observed in preeclamptic placenta may play a role in the pathogenesis of preeclampsia by inducing excessive apoptosis in placenta indirectly through enhancing Nodal expression.