Animal models of primary biliary cholangitis: status and challenges.

BACKGROUND: Primary biliary cholangitis (PBC) is an autoimmune liver disease. The aetiology of PBC remains unclear, and its pathogenesis is complex. Animal models are essential to clarify the pathogenesis of PBC and explore the occurrence of early events. MAIN BODY: Herein, we review recent research progress in PBC animal models, including genetically modified, chemically inducible, biologically inducible, and protein-immunised models. Although these animal models exhibit several immunological and pathological features of PBC, they all have limitations that constrain further research and weaken their connection with clinical practice. CONCLUSION: The review will benefit efforts to understand and optimise animal models in order to further clarify PBC pathogenesis and molecular targets for therapeutic interventions.

Combining single-cell transcriptomics and CellTagging to identify differentiation trajectories of human adipose-derived mesenchymal stem cells.

BACKGROUND: Mesenchymal stromal cells (MSCs) have attracted great attention in the application of cell-based therapy because of their pluripotent differentiation and immunomodulatory ability. Due to the limited number of MSCs isolated from donor tissues, a large number of MSCs need to be expanded in a traditional two-dimensional cell culture device to obtain a sufficient therapeutic amount. However, long-term cultivation of MSCs in vitro has been proven to reduce their differentiation potential and change their immunomodulatory characteristics. We aimed to explore the cellular heterogeneity and differentiation potential of different MSCs expanded in vitro and reconstruct the complex cloning track of cells in the process of differentiation. METHODS: Single cell transcriptome sequencing was combined with 'CellTagging', which is a composite barcode indexing method that can capture the cloning history and cell identity in parallel to track the differentiation process of the same cell over time. RESULTS: Through the single-cell transcriptome and CellTagging, we found that the heterogeneity of human adipose tissue derived stem cells (hADSCs) in the early stage of culture was very limited. With the passage, the cells spontaneously differentiated during the process of division and proliferation, and the heterogeneity of the cells increased. By tracing the differentiation track of cells, we found most cells have the potential for multidirectional differentiation, while a few cells have the potential for unidirectional differentiation. One subpopulation of hADSCs with the specific osteoblast differentiation potential was traced from the early stage to the late stage, which indicates that the differentiation trajectories of the cells are determined in the early stages of lineage transformation. Further, considering that all genes related to osteogenic differentiation have not yet been determined, we identified that there are some genes that are highly expressed specifically in the hADSC subsets that can successfully differentiate into osteoblasts, such as Serpin Family E Member 2 (SERPINE2), Secreted Frizzled Related Protein 1 (SFRP1), Keratin 7 (KRT7), Peptidase Inhibitor 16 (PI16), and Carboxypeptidase E (CPE), which may be key regulatory genes for osteogenic induction, and finally proved that the SERPINE2 gene can promote the osteogenic process. CONCLUSION: The results of this study contribute toward the exploration of the heterogeneity of hADSCs and improving our understanding of the influence of heterogeneity on the differentiation potential of cells. Through this study, we found that the SERPINE2 gene plays a decisive role in the osteogenic differentiation of hADSCs, which lays a foundation for establishing a more novel and complete induction system.

TOX promotes follicular helper T cell differentiation in patients with primary Sjögren's syndrome.

OBJECTIVES: Whether naive CD4+ T cells are dysregulated and associated with the overactivation of CD4+ T cells in primary SS (pSS) remains unclear. We aimed to explore the role and underlying mechanism of naive CD4+ T cells in pSS. METHODS: We examined the activation, proliferation and differentiation of naive CD4+ T cells from pSS patients and healthy controls. Differentially expressed genes were identified using RNA sequencing, and were overexpressed or silenced to determine the gene regulating follicular helper T (Tfh) cells. Assay for transposase-accessible chromatin with high-throughput sequencing (ATAC-seq) with chromatin immunoprecipitation with high-throughput sequencing (ChIP-seq) was performed to explore the epigenetic mechanism. Naive CD4+ T cells were treated with pSS-related cytokines to explore the upstream signalling pathway. RESULTS: pSS naive CD4+ T cells had higher potentials of activation, proliferation and differentiation towards Tfh cells. Thymocyte selection-associated high mobility group box protein (TOX) was upregulated in pSS naive CD4+ T cells and promoted T cell activation and Tfh cell polarization. TOX silencing in pSS naive CD4+ T cells downregulated B cell lymphoma 6 (BCL6) expression and altered levels of multiple Tfh-associated genes. ChIP-seq analysis implied that TOX bound to the BCL6 locus, where there were accessible regions found by ATAC-seq. IFN-α induced TOX overexpression, which was attenuated by Janus kinase (JAK) and signal transducer and activator of transcription 1 (STAT1) inhibitors. CONCLUSION: Our data suggest that TOX in pSS naive CD4+ T cells is upregulated, which facilitates Tfh cell differentiation. Mechanistically, IFN-α induces TOX overexpression in naive CD4+ T cells through JAK-STAT1 signalling and TOX regulates BCL6 expression. Therefore, IFN-α-JAK-STAT1 signalling and TOX might be potential therapeutic targets in pSS.

Potential mesenchymal stem cell therapeutics for treating primary biliary cholangitis: advances, challenges, and perspectives.

Primary biliary cholangitis (PBC) is a cholestatic autoimmune liver disease characterized by the gradual destruction of small intrahepatic bile ducts that eventually leads to liver cirrhosis, failure, and even carcinoma. The treatment options for PBC are limited, and the main treatment choices are the US Food and Drug Administration-approved ursodeoxycholic acid and obeticholic acid. However, many patients fail to respond adequately to these drugs and the adverse effects frequently lead to low life quality. For patients with end-stage PBC, liver transplantation remains the only effective treatment. Given their low immunogenicity, prominent immunomodulation property, differentiation potential, and tissue maintenance capacity, mesenchymal stem cells (MSCs) are emerging as new options for treating liver diseases, including PBC. Accumulating evidence from basic research to clinical studies supports the positive effects of MSC-based therapy for treating PBC. In this review, we characterized the underlying roles and mechanisms of MSCs for treating liver diseases and highlight recent basic and clinical advances in MSC-based therapy for treating PBC. Finally, the current challenges and perspectives for MSC-based therapy in clinical application are discussed, which could help accelerate the application of MSCs in clinical practice, especially for refractory diseases such as PBC.

EZH2 Promotes T Follicular Helper Cell Differentiation Through Enhancing STAT3 Phosphorylation in Patients With Primary Sjögren's Syndrome.

Objectives: Enhancer of zeste homolog 2 (EZH2) is an epigenetic regulator that plays an essential role in immune system development and autoimmune diseases. This study aimed to characterize the role of EZH2 in the pathogenesis of primary Sjögren's syndrome (pSS). Methods: We analyzed EZH2 expression in two transcriptomic datasets of peripheral blood mononuclear cells (PBMCs) from pSS patients and healthy controls. We measured EZH2 expression in CD4+ T cells, CD8+ T cells, and CD19+ B cells from pSS patients and healthy controls and correlated EZH2 expression with clinical parameters. We also examined the activation, proliferation, and T-cell differentiation of CD4+ T cells using the EZH2 inhibitor GSK126, EZH2 siRNA, and EZH2-expressing vector. We further examined the STAT3 signaling pathway after EZH2 inhibition and detected Tfh differentiation in EZH2-overexpressed CD4+ T cells with STAT3 knocked down. Results: EZH2 was upregulated in GSE164885 and GSE48378. EZH2 expression was higher in pSS CD4+ and CD8+ T cells, and EZH2 expression in circulating pSS CD4+ T cells was positively correlated with IgG, IgA, ESR, RF, and the circulating Tfh population. EZH2 inhibition and silencing EZH2 suppressed activation, proliferation, and Tfh differentiation. Furthermore, overexpressing EZH2 promoted activation, proliferation, and Tfh differentiation in CD4+ T cells. EZH2 inhibition attenuated STAT3 phosphorylation in CD4+ T cells. STAT3 knockdown abrogated EZH2-promoted Tfh differentiation. Conclusions: EZH2 expression was abnormally elevated in pSS CD4+ T cells, which facilitated Tfh differentiation of CD4+ T cells by enhancing STAT3 phosphorylation. EZH2 promotes Tfh differentiation and might be implicated in pSS pathogenesis.

LncRNA LYPLAL1-AS1 rejuvenates human adipose-derived mesenchymal stem cell senescence via transcriptional MIRLET7B inactivation.

BACKGROUND: Mesenchymal stem cell (MSC) senescence is a phenotype of aging. Long noncoding RNAs (lncRNAs) are emerging as potential key regulators of senescence. However, the role of lncRNAs in MSC senescence remains largely unknown. RESULTS: We performed transcriptome analysis in senescent human adipose-derived MSCs (hADSCs) and identified that the lncRNA LYPLAL1 antisense RNA1 (LYPLAL1-AS1) was significantly downregulated in senescent hADSCs. LYPLAL1-AS1 expression in peripheral blood was lower in middle-aged healthy donors than in young adult donors, and correlated negatively with age. Knockdown of LYPLAL1-AS1 accelerated hADSC senescence, while LYPLAL1-AS1 overexpression attenuated it. Chromatin isolation by RNA purification (ChIRP) sequencing indicated that LYPLAL1-AS1 bound to the MIRLET7B promoter region and suppressed its transcription activity, as demonstrated by dual-luciferase assay. miR-let-7b, the transcript of MIRLET7B, was upregulated during hADSC senescence and was regulated by LYPLAL1-AS1. Furthermore, miR-let-7b mimics promoted hADSC senescence, while the inhibitors repressed it. Finally, LYPLAL1-AS1 overexpression reversed miR-let-7b-induced hADSC senescence. CONCLUSIONS: Our data demonstrate that LYPLAL1-AS1 rejuvenates hADSCs through the transcriptional inhibition of MIRLET7B. Our work provides new insights into the mechanism of MSC senescence and indicates lncRNA LYPLAL1-AS1 and miR-let-7b as potential therapeutic targets in aging.

MicroRNA-494-3p Exacerbates Renal Epithelial Cell Dysfunction by Targeting SOCS6 under High Glucose Treatment.

BACKGROUND: Diabetic nephropathy is a common complication of the kidneys induced by diabetes and is the main cause of end-stage renal disease. MicroRNA-494-3p was reported to be upregulated in renal tissues collected from db/db mice, but its specific role in diabetic nephropathy was still unclear. This study aimed to explore the effect of miR-494-3p on renal fibrosis using an in vitro cell model of diabetic nephropathy. METHODS: After human renal tubular epithelial cells (HK-2) were treated with high glucose (HG), the viability and apoptosis of cells were examined by CCK-8 assays and flow cytometry analyses. Additionally, protein levels of fibronectin, collagen I, collagen III, collagen IV, and epithelial-mesenchymal transition (EMT) markers in HG-induced HK-2 cells were quantified by Western blotting. miR-494-3p expression in HK-2 cells was detected by reverse-transcription quantitative polymerase chain reaction. The binding relation between miR-494-3p and the messenger RNA suppressor of cytokine signaling 6 (SOCS6) was detected by luciferase reporter assays. RESULTS: HG reduced cell viability and enhanced cell apoptosis in a time- or concentration-dependent manner. Additionally, HG induced collagen accumulation and triggered the EMT process. miR-494-3p was upregulated in HG-treated HK-2 cells. miR-494-3p inhibition alleviated HG-induced cell dysfunction. Mechanistically, miR-494-3p bound with SOCS6 and negatively regulated SOCS6 expression. Moreover, silencing SOCS6 rescued the suppressive effect of miR-499-5p inhibition on HG-induced cell dysfunction. CONCLUSION: miR-494-3p aggravates renal fibrosis, EMT process, and cell apoptosis by targeting SOCS6, suggesting that the miR-494-3p/SOCS6 axis may become a potential strategy for the treatment of diabetic nephropathy.

Erratum to "MiRNA-10b Reciprocally Stimulates Osteogenesis and Inhibits Adipogenesis Partly through the TGF-ß/SMAD2 Signaling Pathway".

[This corrects the article on p. 1058 in vol. 9, PMID: 30574418.].

Mesenchymal stem cell treatment improves outcome of COVID-19 patients via multiple immunomodulatory mechanisms.

The infusion of coronavirus disease 2019 (COVID-19) patients with mesenchymal stem cells (MSCs) potentially improves clinical symptoms, but the underlying mechanism remains unclear. We conducted a randomized, single-blind, placebo-controlled (29 patients/group) phase II clinical trial to validate previous findings and explore the potential mechanisms. Patients treated with umbilical cord-derived MSCs exhibited a shorter hospital stay (P = 0.0198) and less time required for symptoms remission (P = 0.0194) than those who received placebo. Based on chest images, both severe and critical patients treated with MSCs showed improvement by day 7 (P = 0.0099) and day 21 (P = 0.0084). MSC-treated patients had fewer adverse events. MSC infusion reduced the levels of C-reactive protein, proinflammatory cytokines, and neutrophil extracellular traps (NETs) and promoted the maintenance of SARS-CoV-2-specific antibodies. To explore how MSCs modulate the immune system, we employed single-cell RNA sequencing analysis on peripheral blood. Our analysis identified a novel subpopulation of VNN2+ hematopoietic stem/progenitor-like (HSPC-like) cells expressing CSF3R and PTPRE that were mobilized following MSC infusion. Genes encoding chemotaxis factors - CX3CR1 and L-selectin - were upregulated in various immune cells. MSC treatment also regulated B cell subsets and increased the expression of costimulatory CD28 in T cells in vivo and in vitro. In addition, an in vivo mouse study confirmed that MSCs suppressed NET release and reduced venous thrombosis by upregulating kindlin-3 signaling. Together, our results underscore the role of MSCs in improving COVID-19 patient outcomes via maintenance of immune homeostasis.

Human Adipose Mesenchymal Stem Cell-derived Exosomes Protect Mice from DSS-Induced Inflammatory Bowel Disease by Promoting Intestinal-stem-cell and Epithelial Regeneration.

Inflammatory bowel disease (IBD) remains a severe disease for most patients, with its incidence and prevalence increasingly globally. Currently, there is no effective treatments for IBD, and traditional treatments have multiple side effects. Therefore, novel therapeutic strategies or alternative drugs are urgently needed. Previous studies have shown that mesenchymal stem cell-derived exosomes have exhibited promising therapeutic effects on inflammatory disease. Here, we performed intravenous injection of human adipose mesenchymal stem cell (hADSC)-derived exosomes (hADSC-Exo) in a DSS-induced IBD mouse model and found that hADSC-Exo promoted functional recovery, downregulated inflammatory responses, reduced intestine cell apoptosis, increased epithelial regeneration and maintained intestinal barrier integrity. Moreover, we established a colon organoid, hADSC-Exo and TNF-α co-cultured system to explore the protective effect of hADSC-Exo on integrity of intestine mucosa and epithelial regeneration. We showed that hADSC-Exo not only can promote the proliferation and regeneration of Lgr5+ ISCs and epithelial cells but also ameliorate the inflammation damage in TNF-α induced inflammatory damaged mice colon organoids. Taken together, our findings indicate that hADSC-Exo protects intestine integrity, activates intestine epithelial cell and ISCs proliferation, suggesting that hADSC-Exo might be a potential effective treatment approach for IBD. We also provide a theoretical basis for new therapeutic strategies for cell-free therapy in inflammatory bowel disease.

Long Non-coding RNA Regulation of Mesenchymal Stem Cell Homeostasis and Differentiation: Advances, Challenges, and Perspectives.

Given the self-renewal, multi-differentiation, immunoregulatory, and tissue maintenance properties, mesenchymal stem cells (MSCs) are promising candidates for stem cell-based therapies. Breakthroughs have been made in uncovering MSCs as key contributors to homeostasis and the regenerative repair of tissues and organs derived from three germ layers. MSC differentiation into specialized cell types is sophisticatedly regulated, and accumulating evidence suggests long non-coding RNAs (lncRNAs) as the master regulators of various biological processes including the maintenance of homeostasis and multi-differentiation functions through epigenetic, transcriptional, and post-translational mechanisms. LncRNAs are ubiquitous and generally referred to as non-coding transcripts longer than 200 bp. Most lncRNAs are evolutionary conserved and species-specific; however, the weak conservation of their sequences across species does not affect their diverse biological functions. Although numerous lncRNAs have been annotated and studied, they are nevertheless only the tip of the iceberg; the rest remain to be discovered. In this review, we characterize MSC functions in homeostasis and highlight recent advances on the functions and mechanisms of lncRNAs in regulating MSC homeostasis and differentiation. We also discuss the current challenges and perspectives for understanding the roles of lncRNAs in MSC functions in homeostasis, which could help develop promising targets for MSC-based therapies.

Ten-year survival analysis of patients with primary Sjögren's syndrome in China: a national prospective cohort study.

AIMS: To investigate the long-term survival of patients with primary Sjögren's syndrome (pSS) in China. METHODS: Patients with pSS who fulfilled the 2002 American-European Consensus Group classification criteria were prospectively enrolled from 2004 to 2011. Their baseline clinical, laboratory, and therapeutic data were collected. The primary endpoint was all-cause death by January 2018. The standard mortality ratio (SMR) was calculated by comparing with age-matched and sex-matched mortality data of the general population. Kaplan-Meier curves were obtained by time-to-event analysis. Univariate and multivariate Cox hazards regression analyses were performed to identify risk factors for mortality. RESULTS: A total of 1054 patients were enrolled and 834 patients were followed up for a median of 94.8 months, with 48 confirmed deaths. The total SMR was 3.63 [95% confidence interval (CI) 2.60-4.66]. The 3-, 5-, and 10-year survival rates were 98.4%, 97.5%, and 92.9%, respectively. Infection, malignancy, and respiratory failure were the top three causes of mortality. We identified male sex [hazard ratio (HR) = 3.00, 95% CI 1.23-7.31], age at diagnosis ⩾50 years of age (HR = 7.69, 95% CI 3.01-19.62), thrombocytopenia (HR = 1.93, 95% CI 1.01-3.72), and interstitial lung disease (HR = 5.96, 95% CI 2.24-15.82) as the independent prognostic factors of death. CONCLUSIONS: The mortality rates of Chinese patients with pSS are higher than those of the general population. Male patients of elder age at diagnosis complicated with thrombocytopenia and interstitial lung disease might be suggestive for poorer survival and require closer follow up.

Long noncoding RNA LYPLAL1-AS1 regulates adipogenic differentiation of human mesenchymal stem cells by targeting desmoplakin and inhibiting the Wnt/ß-catenin pathway.

Long noncoding RNAs are crucial factors for modulating adipogenic differentiation, but only a few have been identified in humans. In the current study, we identified a previously unknown human long noncoding RNA, LYPLAL1-antisense RNA1 (LYPLAL1-AS1), which was dramatically upregulated during the adipogenic differentiation of human adipose-derived mesenchymal stem cells (hAMSCs). Based on 5' and 3' rapid amplification of cDNA ends assays, full-length LYPLAL1-AS1 was 523 nt. Knockdown of LYPLAL1-AS1 decreased the adipogenic differentiation of hAMSCs, whereas overexpression of LYPLAL1-AS1 enhanced this process. Desmoplakin (DSP) was identified as a direct target of LYPLAL1-AS1. Knockdown of DSP enhanced adipogenic differentiation and rescued the LYPLAL1-AS1 depletion-induced defect in adipogenic differentiation of hAMSCs. Further experiments showed that LYPLAL1-AS1 modulated DSP protein stability possibly via proteasome degradation, and the Wnt/ß-catenin pathway was inhibited during adipogenic differentiation regulated by the LYPLAL1-AS1/DSP complex. Together, our work provides a new mechanism by which long noncoding RNA regulates adipogenic differentiation of human MSCs and suggests that LYPLAL1-AS1 may serve as a novel therapeutic target for preventing and combating diseases related to abnormal adipogenesis, such as obesity.

Lnc13728 facilitates human mesenchymal stem cell adipogenic differentiation via positive regulation of ZBED3 and downregulation of the WNT/ß-catenin pathway.

BACKGROUND: Obesity has received increasing attention because of its widespread worldwide occurrence and many threats to health. Human adipose-derived mesenchymal stem cells (hADSCs) are a critical source of adipocytes. Long noncoding RNAs (lncRNAs) play pivotal roles in cell fate determination and differentiation. The objective of the present study was to identify and investigate the function and regulatory mechanism of lncRNAs on adipogenic differentiation of hADSCs. METHODS: We used lncRNA arrays to identify the prominent differentially expressed lncRNAs before and after hADSC adipogenic differentiation and verified their biological function through antisense oligonucleotide knockdown or lentivirus overexpression. The adipogenic differentiation of hADSCs was assessed by oil red O staining as well as the mRNA and protein levels of adipogenic marker genes through qRT-PCR and western blot. Bioinformatic tool LncPro and immunofluorescence was performed to uncover the interaction between lnc13728 and ZBED3. WNT/ß-catenin signaling pathway was evaluated by western blot and immunofluorescence. RESULTS: The lncRNA arrays showed that lnc13728 expression was significantly upregulated after hADSC adipogenic differentiation and was correlated positively with the expression of the adipogenesis-related genes in human adipose tissue. Lnc13728 knockdown in hADSCs suppressed the expression of the adipogenesis-related genes at both mRNA and protein level and weakened lipid droplet production. Accordingly, lnc13728 overexpression enhanced hADSC adipogenic differentiation. Beyond that, lnc13728 co-localized with ZBED3 in the cytoplasm and regulated its expression positively. Downregulating ZBED3 had a negative effect on adipogenic differentiation, while the expression of WNT/ß-catenin signaling pathway-related proteins was upregulated. CONCLUSIONS: Lnc13728 promotes hADSC adipogenic differentiation possibly by positively regulating the expression of ZBED3 which plays a role in inhibiting the WNT/ß-catenin pathway.

Mesenchymal stem cell-based treatment in autoimmune liver diseases: underlying roles, advantages and challenges.

Autoimmune liver disease (AILD) is a series of chronic liver diseases with abnormal immune responses, including autoimmune hepatitis (AIH), primary biliary cholangitis (PBC), and primary sclerosing cholangitis (PSC). The treatment options for AILD remain limited, and the adverse side effects of the drugs that are typically used for treatment frequently lead to a low quality of life for AILD patients. Moreover, AILD patients may have a poor prognosis, especially those with an incomplete response to first-line treatment. Mesenchymal stem cells (MSCs) are pluripotent stem cells with low immunogenicity and can be conveniently harvested. MSC-based therapy is emerging as a promising approach for treating liver diseases based on their advantageous characteristics of immunomodulation, anti-fibrosis effects, and differentiation to hepatocytes, and accumulating evidence has revealed the positive effects of MSC therapy in AILD. In this review, we first summarize the mechanisms, safety, and efficacy of MSC treatment for AILD based on work in animal and clinical studies. We also discuss the challenges of MSC therapy in clinical applications. In summary, although promising data from preclinical studies are now available, MSC therapy is currently far for being applied in clinical practice, thus developing MSC therapy in AILD is still challenging and warrants further research.

The role of the tyrosine kinase Lyn in allergy and cancer.

With worsening air pollution brought by global social development, the prevalence of allergic diseases has increased dramatically in the past few decades. The novel Lck/yes-related protein tyrosine kinase (Lyn) belongs to the Src kinase family (SFK) and plays a pivotal role in the pathogenesis of inflammation, tumor, and allergy. This signaling molecule is vital in the IgE/FcεRI signaling pathway that regulates allergy. The Lyn-FcεRIß interaction is essential for mast cell activation. The signaling pathway of Lyn has become the focus of immune, inflammatory, tumor, and allergy research. This molecule has positive and negative regulatory effects, which have attracted researchers' attention. This paper reviews the basic characteristics of Lyn and its regulatory mechanism and role in tumor and other diseases, specifically in allergies.

Transplantation of ACE2- Mesenchymal Stem Cells Improves the Outcome of Patients with COVID-19 Pneumonia.

A coronavirus (HCoV-19) has caused the novel coronavirus disease (COVID-19) outbreak in Wuhan, China. Preventing and reversing the cytokine storm may be the key to save the patients with severe COVID-19 pneumonia. Mesenchymal stem cells (MSCs) have been shown to possess a comprehensive powerful immunomodulatory function. This study aims to investigate whether MSC transplantation improves the outcome of 7 enrolled patients with COVID-19 pneumonia in Beijing YouAn Hospital, China, from Jan 23, 2020 to Feb 16, 2020. The clinical outcomes, as well as changes of inflammatory and immune function levels and adverse effects of 7 enrolled patients were assessed for 14 days after MSC injection. MSCs could cure or significantly improve the functional outcomes of seven patients without observed adverse effects. The pulmonary function and symptoms of these seven patients were significantly improved in 2 days after MSC transplantation. Among them, two common and one severe patient were recovered and discharged in 10 days after treatment. After treatment, the peripheral lymphocytes were increased, the C-reactive protein decreased, and the overactivated cytokine-secreting immune cells CXCR3+CD4+ T cells, CXCR3+CD8+ T cells, and CXCR3+ NK cells disappeared in 3-6 days. In addition, a group of CD14+CD11c+CD11bmid regulatory DC cell population dramatically increased. Meanwhile, the level of TNF-α was significantly decreased, while IL-10 increased in MSC treatment group compared to the placebo control group. Furthermore, the gene expression profile showed MSCs were ACE2- and TMPRSS2- which indicated MSCs are free from COVID-19 infection. Thus, the intravenous transplantation of MSCs was safe and effective for treatment in patients with COVID-19 pneumonia, especially for the patients in critically severe condition.

Integrative Exome Sequencing Analysis in Castration-Resistant Prostate Cancer in Chinese Population.

BACKGROUND: Castration-resistant Prostate Cancer (CRPC) is a fatal disease with rapid growth. The malignancy usually presents with metastasis and poor prognosis, and causes 100% mortality. Therefore, the treatment of CRPC is extremely challenging, and its pathogenesis need to be elucidated urgently. OBJECTIVE: The high throughput sequencing technology was used to sequence the whole exome associated with CRPC, to explore the molecular mechanism of CRPC, and to find the potential therapeutic targets. METHODS: We performed whole-exome sequencing of FFPE tissue from 11 Chinese adult male patients. Genomic DNA was fragmented and enriched for whole-exome sequencing using the QiAamp DNA FFPE Tissue KIT, sequenced on an Illumina HiSeq2000 platform, and the relevant genes were analyzed using biological information. Finally, immunohistochemistry method was used to detect the phosphorylation level of LATS1 in CRPC tissues of MST1 mutant and non-mutant patients. RESULTS: We have screened 85 significant mutant genes with relatively high mutation rates of TP53, AR, KMT2, DMAPK1, PIK3R1, SH2B3, WHSC1, KMT2D, MST1 and MAPK1. We first found that MST1 has multiple mutations in CRPC patients, and the MST1 plays an important role in the Hippo pathway. Immunohistochemistry results showed that the phosphorylation level of LATS1 in the mutant patients was significantly lower than that in the non-mutant patients. CONCLUSION: We speculate that MST1 would be a new potential target for the treatment of CRPC by regulating Hippo signaling pathway. The results provided an important clue to the molecular mechanism of CRPC.

Long noncoding RNA ANCR inhibits the differentiation of mesenchymal stem cells toward definitive endoderm by facilitating the association of PTBP1 with ID2.

The generation of definitive endoderm (DE) cells in sufficient numbers is a prerequisite for cell-replacement therapy for liver and pancreatic diseases. Previously, we reported that human adipose-derived mesenchymal stem cells (hAMSCs) can be induced to DE lineages and subsequent functional cells. Clarifying the regulatory mechanisms underlying the fate conversion from hAMSCs to DE is helpful for developing new strategies to improve the differentiation efficiency from hAMSCs to DE organs. Long noncoding RNAs (lncRNAs) have been shown to play pivotal roles in developmental processes, including cell fate determination and differentiation. In this study, we profiled the expression changes of lncRNAs and found that antidifferentiation noncoding RNA (ANCR) was downregulated during the differentiation of both hAMSCs and embryonic stem cells (ESCs) to DE cells. ANCR knockdown resulted in the elevated expression of DE markers in hAMSCs, but not in ESCs. ANCR overexpression reduced the efficiency of hAMSCs to differentiate into DE cells. Inhibitor of DNA binding 2 (ID2) was notably downregulated after ANCR knockdown. ID2 knockdown enhanced DE differentiation, whereas overexpression of ID2 impaired this process in hAMSCs. ANCR interacts with RNA-binding polypyrimidine tract-binding protein 1 (PTBP1) to facilitate its association with ID2 mRNA, leading to increased ID2 mRNA stability. Thus, the ANCR/PTBP1/ID2 network restricts the differentiation of hAMSCs toward DE. Our work highlights the inherent discrepancies between hAMSCs and ESCs. Defining hAMSC-specific signaling pathways might be important for designing optimal differentiation protocols for directing hAMSCs toward DE.