MSC-derived exosomes attenuate hepatic fibrosis in primary sclerosing cholangitis through inhibition of Th17 differentiation.

Primary sclerosing cholangitis (PSC) is an autoimmune cholangiopathy characterized by chronic inflammation of the biliary epithelium and periductal fibrosis, with no curative treatment available, and liver transplantation is inevitable for end-stage patients. Human placental mesenchymal stem cell (hpMSC)-derived exosomes have demonstrated the ability to prevent fibrosis, inhibit collagen production and possess immunomodulatory properties in autoimmune liver disease. Here, we prepared hpMSC-derived exosomes (ExoMSC) and further investigated the anti-fibrotic effects and detailed mechanism on PSC based on Mdr2-/- mice and multicellular organoids established from PSC patients. The results showed that ExoMSC ameliorated liver fibrosis in Mdr2-/- mice with significant collagen reduction in the preductal area where Th17 differentiation was inhibited as demonstrated by RNAseq analysis, and the percentage of CD4+IL-17A+T cells was reduced both in ExoMSC-treated Mdr2-/- mice (Mdr2-/--Exo) in vivo and ExoMSC-treated Th17 differentiation progressed in vitro. Furthermore, ExoMSC improved the hypersecretory phenotype and intercellular interactions in the hepatic Th17 microenvironment by regulating PERK/CHOP signaling as supported by multicellular organoids. Thus, our data demonstrate the anti-fibrosis effect of ExoMSC in PSC disease by inhibiting Th17 differentiation, and ameliorating the Th17-induced microenvironment, indicating the promising potential therapeutic role of ExoMSC in liver fibrosis of PSC or Th17-related diseases.

A novel HIF2A mutation causes dyslipidemia and promotes hepatic lipid accumulation.

Hypoxia-inducible factor-2α (HIF-2α) is a transcription factor responsible for regulating genes related to angiogenesis and metabolism. This study aims to explore the effect of a previously unreported mutation c.C2473T (p.R825S) in the C-terminal transactivation domain (CTAD) of HIF-2α that we detected in tissue of patients with liver disease. We sequenced available liver and matched blood samples obtained during partial liver resection or liver transplantation performed for clinical indications including hepatocellular carcinoma and liver failure. In tandem, we constructed cell lines and a transgenic mouse model bearing the corresponding identified mutation in HIF-2α from which we extracted primary hepatocytes. Lipid accumulation was evaluated in these cells and liver tissue from the mouse model using Oil Red O staining and biochemical measurements. We identified a mutation in the CTAD of HIF-2α (c.C2473T; p.R825S) in 5 of 356 liver samples obtained from patients with hepatopathy and dyslipidemia. We found that introduction of this mutation into the mouse model led to an elevated triglyceride level, lipid droplet accumulation in liver of the mutant mice and in their extracted primary hepatocytes, and increased transcription of genes related to hepatic fatty acid transport and synthesis in the mutant compared to the control groups. In mutant mice and cells, the protein levels of nuclear HIF-2α and its target perilipin-2 (PLIN2), a lipid droplet-related gene, were also elevated. Decreased lipophagy was observed in mutant groups. Our study defines a subpopulation of dyslipidemia that is caused by this HIF-2α mutation. This may have implications for personalized treatment.

Triple-Combination Immunogenic Nanovesicles Reshape the Tumor Microenvironment to Potentiate Chemo-Immunotherapy in Preclinical Cancer Models.

Immune checkpoint blockade (ICB) therapies have had a tremendous impact on cancer therapy. However, most patients harbor a poorly immunogenic tumor microenvironment (TME), presenting overwhelming de novo refractoriness to ICB inhibitors. To address these challenges, combinatorial regimens that employ chemotherapies and immunostimulatory agents are urgently needed. Here, a combination chemoimmunotherapeutic nanosystem consisting of a polymeric monoconjugated gemcitabine (GEM) prodrug nanoparticle decorated with an anti-programmed cell death-ligand 1 (PD-L1) antibody (αPD-L1) on the surface and a stimulator of interferon genes (STING) agonist encapsulated inside is developed. Treatment with GEM nanoparticles upregulates PD-L1 expression in ICB-refractory tumors, resulting in augmented intratumor drug delivery in vivo and synergistic antitumor efficacy via activation of intratumor CD8+ T cell responses. Integration of a STING agonist into the αPD-L1-decorated GEM nanoparticles further improves response rates by transforming low-immunogenic tumors into inflamed tumors. Systemically administered triple-combination nanovesicles induce robust antitumor immunity, resulting in durable regression of established large tumors and a reduction in the metastatic burden, coincident with immunological memory against tumor rechallenge in multiple murine tumor models. These findings provide a design rationale for synchronizing STING agonists, PD-L1 antibodies, and chemotherapeutic prodrugs to generate a chemoimmunotherapeutic effect in treating ICB-nonresponsive tumors.

Characteristic Analysis of Featured Genes Associated with Cholangiocarcinoma Progression.

The noninvasive diagnosis of cholangiocarcinoma (CCA) is insufficiently accurate. Therefore, the discovery of new prognostic markers is vital for the understanding of the CCA mechanism and related treatment. The information on CCA patients in The Cancer Genome Atlas database was used for weighted gene co-expression network analysis. Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were applied to analyze the modules of interest. By using receiver operating characteristic (ROC) analysis to analyze the Human Protein Atlas (HPA), the featured genes were subsequently verified. In addition, clinical samples and GSE119336 cohort data were also collected for the validation of these hub genes. Using WGCNA, we identified 61 hub genes that regulated the progression and prognosis of CCA. Eight hub genes (VSNL1, TH, PCP4, IGDCC3, RAD51AP2, MUC2, BUB1, and BUB1B) were identified which exhibited significant interactions with the tumorigenic mechanism and prognosis of CCA. In addition, GO and KEGG clarified that the blue and magenta modules were involved with chromosome segregation, mitotic and oocyte meiosis, the cell cycle, and sister chromatid segregation. Four hub genes (VSNL1, PCP4, BUB1, and BUB1B) were also verified as featured genes of progression and prognosis by the GSE119336 cohort data and five human tissue samples.

Efficacy and Safety of PD-1/PD-L1 Checkpoint Inhibitors versus Anti-PD-1/PD-L1 Combined with Other Therapies for Tumors: A Systematic Review.

OBJECTIVE: In recent years, the anti-programmed cell death protein-1 and its ligand (PD-1/PD-L1) or combination therapies have been recommended as an alternative emerging choice of treatment for oncology patients. However, the efficacy and adverse events of different combination strategies for the treatment of tumors remain controversial. METHODS: PubMed, Embase, Cochrane Library, the American Society of Clinical Oncology (ASCO), and the European Society of Medicine Oncology (ESMO) were searched from database inception until 16 February 2022. The endpoints of objective response rate (ORR), disease control rate (DCR), overall survival (OS), progression-free survival (PFS), and adverse events (AEs) were analyzed from different treatment schemes and tumor types. The protocol was registered in PROSPERO (CRD42022328927). RESULTS: This meta-analysis included forty-eight eligible studies. Combination therapy has improved ORR (RR = 1.40, p < 0.001), DCR (RR = 1.22, p < 0.001), and PFS (the median survival ratio (MSR) was estimated to be 1.475 p < 0.001) compared to anti-PD-1/PD-L1 but had no significant benefit on OS (MSR was estimated to be 1.086 p = 0.117). Besides, combination treatment strategies are more toxic in any grade AEs (RR = 1.13, p < 0.001) and grade 3-5 AEs (RR = 1.81, p < 0.001). CONCLUSIONS: Treatment with PD-1/PD-L1 inhibitors in combination with other antitumor therapies improve patients' ORR, DCR, and PFS compared to anti-PD-1/PD-L1. However, it is regrettable that there is no benefit to OS and an increased risk of AEs in combinatorial therapies.

Highly Efficient Methods to Culture Mouse Cholangiocytes and Small Intestine Organoids.

Background: Organoids, which enable disease modeling and drug screening closer to an in vivo environment, can be isolated and grown from organs such as the brain, small intestine, kidney, lungs, and liver. To facilitate the establishment of liver and small intestinal organoids, we developed efficient protocols for cholangiocytes and intestine crypts collecting and organoid culturing. Methods: Cholangiocytes were collected from intrahepatic bile ducts, the gallbladder, and small intestine crypts by gravity settling and multistep centrifugation methods. The cells isolated were embedded with Matrigel and grew in three-dimensional spheroids in a suitable culture medium. The stability of organoid cells was assessed by subculture, cryopreservation, and thawing. RNA and DNA extraction of organoids, as well as immunostaining procedure, were also optimized. Hand-picking procedures were developed and performed to ensure similar growth characteristics of organoids. Results: A large number of cholangiocytes and small intestine crypts were collected under these protocols. Cholangiocytes developed into cyst-like structures after 3-4 days in Matrigel. After 1-2 weeks of cultivation, small intestinal organoids (in-orgs) developed buds and formed a mature structure. Compared to organoids derived from the gallbladder, cholangiocyte organoids (Cho-orgs) from intrahepatic the bile ducts grew more slowly but had a longer culture term, expressed the cholangiocytes markers Krt19 and Krt7, and recapitulated in vivo tissue organization. Conclusions: Our protocols simplified the cell collection procedure and avoided the possibility of exposing tissue-derived stem cells to mechanical damage or chemical injury by gravity settling and multistep centrifugation. In addition, our approach allowed similar growth characteristics of organoids from different mammalian tissue sources. The protocol requires 2-4 weeks to establish a stable organoid growth system. Organoids could be stably passaged, cryopreserved, and recovered under protocol guidance. Besides, the organoids of cholangiocytes and small intestines retained their original tissue characteristics, such as tissue-specific marker expression, which prepares them for further experiments such as preclinical in vitro trials and mechanism research studies.

Mesenchymal stem cell treatment restores liver macrophages homeostasis to alleviate mouse acute liver injury revealed by single-cell analysis.

Acute liver injury (ALI) is characterized by massive hepatocyte necrosis and subsequent recruitment of myeloid cells to liver. Mesenchymal stem cells (MSCs) have therapeutic potential for ALI through their immunoregulation on macrophages, but the mechanism is not completely clear due to the heterogeneity and controversy of liver macrophages. Here, we detected the survival rate, biochemical indexes, histopathology, and inflammatory chemokine levels to assess the efficacy of MSC treatment on CCl4-induced ALI of C57BL/6 mice. Furthermore, flow cytometry and single-cell RNA sequencing (scRNA-Seq) were used to precisely distinguish macrophage populations and reveal the immunoregulation of MSCs. MSC treatment could effectively alleviate ALI and mitigate the recruitment of mononuclear phagocytes. Flow cytometry and scRNA-Seq analyses collectively indicated that there were monocytes with high Ly6C expression and heterogeneous monocyte-derived macrophages (MoMF) with low Ly6C expression in liver. Ly6Chi pro-inflammatory monocytes and Ly6Clo MoMF with powerful phagocytosis dominated during the acute injury period. MSC treatment promoted the transition from Ly6Chi to Ly6Clo population, inhibit the proinflammatory function of monocytes and promote the lysosomal function of MoMF. Furthermore, MSCs attenuated the recruitment of neutrophils by reducing the expression of CXCL2 of MoMF. MoMF with high expression of arginase 1 appeared during the recovery period, and MSCs could increase their expression of arginase 1, which may promote liver repair. To sum up, we demonstrated the characteristics of distinct MoMF during different periods of ALI and revealed their functional changes after MSC treatment, providing immunotherapeutic targets for MSC treatment of ALI.

Mesenchymal stem cells protect against ferroptosis via exosome-mediated stabilization of SLC7A11 in acute liver injury.

Mesenchymal stem cells (MSCs) have attracted interest for their potential to alleviate liver injury. Here, the protective effect of MSCs on carbon tetrachloride (CCl4)-induced acute liver injury (ALI) was investigated. In this study, we illustrated a novel mechanism that ferroptosis, a newly recognized form of regulated cell death, contributed to CCl4-induced ALI. Subsequently, based on the in vitro and in vivo evidence that MSCs and MSC-derived exosomes (MSC-Exo) treatment achieved pathological remission and inhibited the production of lipid peroxidation, we proposed an MSC-based therapy for CCl4-induced ALI. More intriguingly, treatment with MSCs and MSC-Exo downregulated the mRNA level of prostaglandin-endoperoxide synthase 2 (Ptgs2) and lipoxygenases (LOXs) while it restored the protein level of SLC7A11 in primary hepatocytes and mouse liver, indicating that the inhibition of ferroptosis partly accounted for the protective effect of MSCs and MSC-Exo on ALI. We further revealed that MSC-Exo-induced expression of SLC7A11 protein was accompanied by increasing of CD44 and OTUB1. The aberrant expression of ubiquitinated SLC7A11 triggered by CCl4 could be rescued with OTUB1-mediated deubiquitination, thus strengthening SLC7A11 stability and thereby leading to the activation of system XC- to prevent CCl4-induced hepatocyte ferroptosis. In conclusion, we showed that MSC-Exo had a protective role against ferroptosis by maintaining SLC7A11 function, thus proposing a novel therapeutic strategy for ferroptosis-induced ALI.

Stem cell therapy for Crohn's disease: systematic review and meta-analysis of preclinical and clinical studies.

BACKGROUND: We explored whether stem cell therapy was effective for animal models and patients with Crohn's disease (CD). METHODS: We searched five online databases. The relative outcomes were analyzed with the aid of GetData Graph Digitizer 2.26 and Stata 16.0 software. The SYRCLE risk of bias tool and the MINORS tool were used to assess study quality. RESULTS: We evaluated 46 studies including 28 animal works (n = 567) and 18 human trials (n = 360). In the animal studies, the disease activity index dramatically decreased in the mesenchymal stem cell (MSC) treatment groups compared to the control group. Rats and mice receiving MSCs exhibited longer colons [mice: standardized mean difference (SMD) 2.84, P = 0.000; rats: SMD 1.44, P = 0.029], lower histopathological scores (mice: SMD - 4.58, p = 0.000; rats: SMD - 1.41, P = 0.000) and lower myeloperoxidase levels (SMD - 6.22, P = 0.000). In clinical trials, stem cell transplantation reduced the CD activity index (SMD - 2.10, P = 0.000), the CD endoscopic index of severity (SMD - 3.40, P = 0.000) and simplified endoscopy score for CD (SMD - 1.71, P = 0.000) and improved the inflammatory bowel disease questionnaire score (SMD 1.33, P = 0.305) compared to control values. CD patients maintained high remission rates for 3-24 months after transplantation. CONCLUSIONS: Stem cell transplantation is a valuable supplementary therapy for CD.

Efficacy and safety of combination PD-1/PD-L1 checkpoint inhibitors for malignant solid tumours: A systematic review.

Treatment of multiple malignant solid tumours with programmed death (PD)-1/PD ligand (PD-L) 1 inhibitors has been reported. However, the efficacy and immune adverse effects of combination therapies are controversial. This meta-analysis was performed with PubMed, Web of Science, Medline, EMBASE and Cochrane Library from their inception until January 2020. Random-effect model was adopted because of relatively high heterogeneity. We also calculated hazard ratio (HR) of progression-free survival (PFS), overall survival (OS) and risk ratio (RR) of adverse events (AEs), the incidence of grade 3-5 AEs by tumour subgroup, therapeutic schedules and therapy lines. Nineteen articles were selected using the search strategy for meta-analysis. Combined PD-1/PD-L1 inhibitors prolonged OS and PFS (HR 0.72, P < 0.001) and (HR 0.66, P < 0.001). In addition, incidence of all-grade and grade 3-5 AEs was not significant in the two subgroup analyses (HR 1.01, P = 0.31) and (HR 1.10, P = 0.07), respectively. Our meta-analysis indicated that combination therapy with PD-1/PD-L1 inhibitors had greater clinical benefits and adverse events were not increased significantly.

The efficacy and safety of combined immune checkpoint inhibitors (nivolumab plus ipilimumab): a systematic review and meta-analysis.

BACKGROUND: Currently, nivolumab and ipilimumab are the most widely used immune checkpoint inhibitors. We performed a meta-analysis to evaluate the efficacy and treatment-related adverse events (TRAEs) of nivolumab plus ipilimumab therapy in cancer treatment. METHODS: We examined data from PubMed, Web of Science, EBSCO, and Cochrane Library. Eleven articles fulfilled our criteria, which we divided into 3 groups: nivolumab plus ipilimumab versus nivolumab (the dose used for monotherapy is 3 mg/kg), nivolumab plus ipilimumab versus ipilimumab (the dose used for monotherapy is 3 mg/kg), and nivolumab 1 mg/kg plus ipilimumab 3 mg/kg (N1I3) versus nivolumab 3 mg/kg plus ipilimumab 1 mg/kg (N3I1). We measured the complete response (CR), partial response (PR), objective response rate (ORR), and TRAEs in any grade and grade 3 or higher. RESULTS: The overall effect estimate favored the combined immunotherapy group in terms of the ORR (RR: 1.40, p < 0.001) and PR (RR: 1.50, p < 0.001) than nivolumab alone. Compared with ipilimumab alone, the combined immunotherapy group had better CR (RR: 4.89, p < 0.001), PR (RR: 2.75, p < 0.001), and ORR (RR: 3.31, p < 0.001). Finally, N1I3 showed better PR (RR: 1.35, p = 0.006) and ORR (RR: 1.21, p = 0.03) than N3I1. The incidence of any TRAEs was similar between both groups (RR: 1.05, p = 0.06). However, the incidence of serious adverse events (grade 3 or higher) was lower in group N3I1 than group N1I3 (RR: 1.51, p < 0.001). CONCLUSION: This meta-analysis showed that the curative effect of nivolumab plus ipilimumab was better than that of nivolumab or ipilimumab monotherapy. In the combined immunotherapy group, N1I3 was more effective than N3I1. Although the side effects were slightly increased in N1I3 group, overall safety was acceptable.

Comparison of tenofovir versus entecavir on reducing incidence of hepatocellular carcinoma in chronic hepatitis B patients: A systematic review and meta-analysis.

BACKGROUND AND AIM: Studies had shown that tenofovir (TDF) and entecavir (ETV) are widely used as the first-line therapy to inhibit hepatitis B virus replication, which can reduce the risk of hepatocellular carcinoma (HCC) in chronic hepatitis B (CHB) patients, but it was unclear which nucleos(t)ide analogue was most effective. Therefore, we performed a meta-analysis and a systematic review to compare the incidence of HCC in CHB patients who are either on TDF or ETV. METHODS: For this study, the following databases were searched for clinical trials published from its inception until November 2019: PubMed, Web of Science, MEDLINE, Embase, and Cochrane Library. RESULTS: A total of 11 eligible studies were selected, including 70 864 patients. The meta-analysis showed that TDF was superior to ETV with regard to the incidence of HCC, the incidence of death or transplantation, and virologic response. There were no significant differences in terms of biochemical response and loss of seroconversion response among the entire cohort. CONCLUSIONS: The conclusion was that CHB patients treated with TDF had a reduced incidence of HCC compared with patients treated with ETV.