Mesenchymal stem cells regulate type 2 innate lymphoid cells via regulatory T cells through ICOS-ICOSL interaction.

Group 2 innate lymphoid cells (ILC2s) are recognized as key controllers and effectors of type 2 inflammation. Mesenchymal stem cells (MSCs) have been shown to alleviate type 2 inflammation by modulating T lymphocyte subsets and decreasing TH 2 cytokine levels. However, the effects of MSCs on ILC2s have not been investigated. In this study, we investigated the potential immunomodulatory effects of MSCs on ILC2s in peripheral blood mononuclear cells (PBMCs) from allergic rhinitis patients and healthy subjects. We further investigated the mechanisms involved in the MSC modulation using isolated lineage negative (Lin- ) cells. PBMCs and Lin- cells were cocultured with induced pluripotent stem cell-derived MSCs (iPSC-MSCs) under the stimulation of epithelial cytokines IL-25 and IL-33. And the ILC2 levels and functions were examined and the possible mechanisms were investigated based on regulatory T (Treg) cells and ICOS-ICOSL pathway. iPSC-MSCs successfully decreased the high levels of IL-13, IL-9, and IL-5 in PBMCs in response to IL-25, IL-33, and the high percentages of IL-13+ ILC2s and IL-9+ ILC2s in response to epithelial cytokines were significantly reversed after the treatment of iPSC-MSCs. However, iPSC-MSCs were found directly to enhance ILC2 levels and functions via ICOS-ICOSL interaction in Lin- cells and pure ILC2s. iPSC-MSCs exerted their inhibitory effects on ILC2s via activating Treg cells through ICOS-ICOSL interaction. The MSC-induced Treg cells then suppressed ILC2s by secreting IL-10 in the coculture system. This study revealed that human MSCs suppressed ILC2s via Treg cells through ICOS-ICOSL interaction, which provides further insight to regulate ILC2s in inflammatory disorders.

Mechanisms underlying the protective effects of mesenchymal stem cell-based therapy.

Mesenchymal stem cells (MSCs) have been extensively investigated for the treatment of various diseases. The therapeutic potential of MSCs is attributed to complex cellular and molecular mechanisms of action including differentiation into multiple cell lineages and regulation of immune responses via immunomodulation. The plasticity of MSCs in immunomodulation allow these cells to exert different immune effects depending on different diseases. Understanding the biology of MSCs and their role in treatment is critical to determine their potential for various therapeutic applications and for the development of MSC-based regenerative medicine. This review summarizes the recent progress of particular mechanisms underlying the tissue regenerative properties and immunomodulatory effects of MSCs. We focused on discussing the functional roles of paracrine activities, direct cell-cell contact, mitochondrial transfer, and extracellular vesicles related to MSC-mediated effects on immune cell responses, cell survival, and regeneration. This will provide an overview of the current research on the rapid development of MSC-based therapies.

Increased Group 2 Innate Lymphoid Cells Are Correlated with Eosinophilic Granulocytes in Patients with Allergic Airway Inflammation.

The T helper 2 (Th2)-type response was considered the hypostasis of allergic airway diseases, including asthma and allergic rhinitis (AR). However, more recent studies have suggested that allergic airway inflammation also depends on innate immunity and is closely related to group 2 innate lymphoid cells (ILC2s). This study evaluated the ILC2 levels of asthma subjects, patients with asthma and AR, and healthy individuals, regarding how to investigate the relationship between clinical data and ILC2 levels. It was found that asthma patients and asthma with AR patients had higher ILC2 levels compared to healthy subjects. ILC2s were positively correlated with the percentage of eosinophils in patients with asthma and AR, but not with pulmonary function. ILC2 levels were higher in mild asthma subjects than in patients with severe asthma. This study provides a new interpretation of the pathogenesis of allergic airway inflammation and may provide a new direction for the diagnosis and assessment of allergic airway diseases.

Increased innate type 2 immune response in house dust mite-allergic patients with allergic rhinitis.

Group 2 innate lymphoid cells (ILC2s) are essential in initiating and driving allergic immune responses. However, there were inconsistent findings of the ILC2 levels in allergic rhinitis (AR) patients. This study investigated the ILC2 levels in the peripheral blood of house dust mite (HDM)-sensitized AR patients and their ability to secrete type 2 cytokines. The levels of ILC2s with phenotypic ILC2 characteristics were increased in the HDM-AR patients. The AR patients' symptom score and IL-13 levels were positively associated with the ILC2s in HDM-AR patients. The epithelial cytokine stimulation induced dramatic production of IL-5 and IL-13 in PBMCs of AR patients. We successfully sorted ILC2s from AR patients and identified their ability of type 2 cytokines production. The number of ILC2s increased in the HDM-AR patients and ILC2s produced the amount of TH2 cytokines in the presence of epithelial cytokines, which suggested the important role of ILC2 in AR patients.

Aggregation Induced Emission Fluorogens Based Nanotheranostics for Targeted and Imaging-Guided Chemo-Photothermal Combination Therapy.

Nanotheranostics for biomedical imaging-guided cancer therapy have attracted increasing interest due to their capabilities of both precise tumor diagnosis and high therapeutic efficacy. Among the diverse imaging models, fluorescence imaging have been extensively researched for their high sensitivity, simple operation, and low cost. In this work, aggregation induced emission (AIE) fluorogens based targeted nanotheranostics are facilely fabricated via paclitaxel (PTX) induced assembly of proteins for the first time. Thanks to the unique fluorescence property of AIE fluorogens PhENH2 , the prepared theranostic nanoplatforms can emit bright fluorescence even after being incorporated with the photothermal therapy agent polypyrrole (PPy), which will often decrease or quench the emission of common fluorescence dyes. The target moiety of cyclic arginine-glycine-aspartic acid (cRGD) endows the nanotheranostics with outstanding targeting ability, which can further facilitate the targeted imaging and cancer treatment. As revealed by the in vitro and in vivo experiments, the prepared nanotheranostics human serum albumin-PhENH2 -PPy-PTX-cRGD shows impressive performance in the targeted fluorescence imaging even after intravenous injection for 48 h, and their combined chemo-photothermal therapy is also very effective. These results indicate that AIE fluorogens based nanotheranostics would find a promising prospect in further improved multimodal imaging and imaging guided cancer treatment.

CD40 ligand preferentially modulates immune response and enhances protection against influenza virus.

CD40L, a key regulator of the immune system, was studied as both a targeting ligand and a molecular adjuvant in nucleoprotein (NP)-based host defense against influenza in mouse models with different genetic backgrounds. Adenoviral vectors secreting NP-CD40L fusion protein (denoted as rAd-SNP40L) afforded full protection of immunocompetent and immunocompromised mice (CD40L(-/-) and CD4(-/-)) against lethal influenza infection. Mechanistically, rAd-SNP40L preferentially induced early and persistent B cell germinal center formation, and accelerated Ig isotype-switching and Th1-skewed, NP-specific Ab response. Moreover, it drastically augmented primary and memory NP-specific CTL activity and polyfunctional CD8(+) T cells. The markedly enhanced nonneutralizing Abs and CTLs significantly reduced viral burdens in the lungs of mice upon lethal virus challenge. Data generated from CD40L(-/-) and CD4(-/-) mice revealed that the protection was indeed CD40L mediated but CD4(+) T cell independent, demonstrating the viability of the fusion Ags in protecting immunodeficient hosts. Notably, a single dose of rAd-SNP40L completely protected mice from lethal viral challenge 4 mo after immunization, representing the first report, to our knowledge, on NP in conjunction with a molecular adjuvant inducing a robust and long-lasting memory immune response against influenza. This platform is characterized by an increased in vivo load of CD40-targeted Ag upon the secretion of the fusion protein from adenovirus-infected cells and may represent a promising strategy to enhance the breadth, durability, and potency of Ag-specific immune responses.

Thermoresponsive Substrates Used for the Growth and Controlled Differentiation of Human Mesenchymal Stem Cells.

This communication outlines the advances made in the development of thermoresponsive substrates for human mesenchymal stem cell (hMSC) expansion and subsequent controlled specific and multilineage differentiation from a previous study performed by this group. Previously, the development of an inexpensive and technically accessible method for hMSC expansion and harvesting was reported, using the solvent casting deposition method and thermoresponsive poly(N-isopropylacrylamide). Here, the logical continuation of this work is reported with the multipassage expansion of hMSCs with phenotypic maintenance followed by induced adipogenic, osteogenic, and chondrogenic differentiation. Interestingly, 1 µm thick solvent cast films are not only capable of hosting an expanding population of phenotypically preserved hMSCs similar to tissue culture plastic controls, but also the cells detached via temperature control better maintain their ability to differentiate compared to conventionally trypsinized cells. This approach to hMSC expansion and differentiation can be highly attractive to stem cell researchers where clinical therapies have seen a collective deviation away from the employment of animal derived products such as proteolytic trypsin.

Detection of human enterovirus 71 and Coxsackievirus A16 in an outbreak of hand, foot, and mouth disease in Henan Province, China in 2009.

During 2009, an outbreak of hand, foot, and mouth disease (HFMD) enrolled 490 people in Henan Province, causing the death of two children. In order to investigate the pathogens responsible for this outbreak and characterize their genetic characteristics, a total of 508 clinical specimens (stool, throat swab, and vesicle fluid) were collected from the Center for Disease Control and Prevention of Henan Province. Virological investigations (virus isolation, conventional reverse transcription PCR, and real-time reverse transcription PCR) and phylogenetic analysis were performed. It was found that human enterovirus 71 (EV71) was the main pathogen causing this outbreak, while Coxsackievirus A16 (CoxA16) played only a subsidiary role. Phylogenetic analysis of 24 EV71 isolates collected during the period from March 11 to July 24, 2009 showed that they belonged to subgenotypes C4 and C5. Our study for the first time characterizes the epidemiology of HFMD and EV71 infection in Henan Province in 2009 and provides the first direct evidence of the genotype of EV71 circulating in Henan Province at that time. Our study should facilitate the development of public health measures for the control and prevention of HFMD and EV71 infection in at-risk individuals in China.

Network Pharmacology Combined with Experimental Validation Reveals the Anti-tumor Effect of Duchesnea indica against Hepatocellular Carcinoma.

Context: Duchesnea indica is effective against hepatocellular carcinoma (HCC); however, its underlying mechanism of action remains unclear. Objective: The present study aimed to investigate the potential mechanism of action and effects of D. indica components against HCC. Materials and methods: First, the effects of D. indica against HCC were investigated in vitro and in vivo. For in vitro experiments, HCC cell lines were treated with D. indica solutions at different concentrations (0, 1, 2 mg/mL) and then assessed for cell apoptosis, proliferation, migration, invasion, and angiogenic ability. For in vivo experiments, 24 mice were randomly divided into the following four groups: model group and D. indica low-, medium-, and high-dose groups. Tumor growth and CD34 and Ki67 expression levels were assessed to determine the effects of D. indica on cell proliferation and angiogenic ability. Furthermore, transcriptome sequencing and differential expression analyses were used to identify D. indica-induced differentially expressed genes (DEGs) in HCC cells. Additionally, mass spectrometry was conducted to identify the chemical components of D. indica. Four databases were used to predict the target proteins of these chemical components in HCC. HCC-associated genes were identified from two databases. By intersecting the identified DEGs; target proteins; and HCC-associated genes, key D. indica-regulated HCC-related genes were identified. Subsequently, protein-protein interaction network, network pharmacology, and molecular docking were used to identify the active compounds in D. indica and their likely gene targets. Results: In vitro experiments demonstrated that D. indica induced tumor cell apoptosis and inhibited cell proliferation, migration, invasion, and angiogenic potential. In vivo experiments demonstrated that D. indica inhibited tumor growth in a dose-dependent manner. Bioinformatic analyses identified 49 key D. indica-regulated HCC-related genes, of which FOS, SERPINE1, AKR1C3, and FGF2 were the most significant. Mass spectrometry identified the following five molecules in D. indica with potential anti-HCC activity: 4', 5, 7-trihydroxyflavone; ethyl protocatechuate; 3, 5-dihydroxy-benzoic acid; curculigosaponin A; and curculigine G. Molecular docking validated the interaction between D. indica active compounds and their target proteins in HCC. Conclusions: The present study confirmed the therapeutic effects of D. indica against HCC and identified the key genes and active components that may contribute to its mechanism of action, thereby providing a basis for further research on targeted therapeutics for HCC.

Mechanisms of Potential Therapeutic Utilization of Mesenchymal Stem Cells in COVID-19 Treatment.

The 2019 novel coronavirus disease (COVID-19) has lasted for over 3 years and has seriously affected the regular life trajectory of human beings. The severe acute respiratory syndrome coronavirus 2 (SARS­CoV­2) has caused non-negligible harm to people's respiratory systems and multiple organs. Although the pathogenesis of COVID-19 has been fully elucidated, there is still a lack of effective and specific treatment for COVID-19. Mesenchymal stem cells (MSCs) or MSC-derived extracellular vesicles (MSC-EVs) by far have become the most promising candidates in preclinical studies and clinical trials, and MSC-related therapies have shown their potential to treat severe COVID-19. The multidirectional differentiation potential and immunomodulatory function of MSCs have allowed the cells to exert multiple cellular and molecular actions on different immune cells and organs. It is critical to understand the therapeutic roles of MSCs before entering the clinics for COVID-19 and other diseases. This review summarizes the recent progress of particular mechanisms underlying the immunomodulatory and tissue regenerative effects of MSCs toward COVID-19. We focused on discussing the functional roles of MSC-mediated effects on immune cell responses, cell survival, and organ regeneration. Besides, the novel discoveries and recent findings of MSC clinical application in patients with COVID-19 were highlighted. This will provide an overview of the current research on the rapid development of MSC-based therapies not only for COVID-19 but also for other immune-mediated/immune-dysregulating diseases.

Regulatory T cells in lung disease and transplantation.

Pulmonary disease can refer to the disease of the lung itself or the pulmonary manifestations of systemic diseases, which are often connected to the malfunction of the immune system. Regulatory T (Treg) cells have been shown to be important in maintaining immune homeostasis and preventing inflammatory damage, including lung diseases. Given the increasing amount of evidence linking Treg cells to various pulmonary conditions, Treg cells might serve as a therapeutic strategy for the treatment of lung diseases and potentially promote lung transplant tolerance. The most potent and well-defined Treg cells are Foxp3-expressing CD4+ Treg cells, which contribute to the prevention of autoimmune lung diseases and the promotion of lung transplant rejection. The protective mechanisms of Treg cells in lung disease and transplantation involve multiple immune suppression mechanisms. This review summarizes the development, phenotype and function of CD4+Foxp3+ Treg cells. Then, we focus on the therapeutic potential of Treg cells in preventing lung disease and limiting lung transplant rejection. Furthermore, we discussed the possibility of Treg cell utilization in clinical applications. This will provide an overview of current research advances in Treg cells and their relevant application in clinics.

Cellular microRNA let-7c inhibits M1 protein expression of the H1N1 influenza A virus in infected human lung epithelial cells.

The influenza virus (IV) triggers a series of signalling events inside host cells and induces complex cellular responses. Studies have suggested that host factors play an essential role in IV replication. MicroRNAs (miRNAs) represent a class of small non-coding RNAs that target mRNAs, triggering either translation repression or RNA degradation. Emerging research suggests that host-derived cellular miRNAs are involved in mediating the host-IV interaction. Using miRNA microarrays, we identified several miRNAs aberrantly expressed in IV-infected human lung epithelial cells (A549). Specifically, miR-let-7c was highly up-regulated in IV-infected A549 cells. PITA and miRanda database screening indicated that the let-7c seed sequence is a perfect complementary sequence match to the 3' untranslated region (UTR) of viral gene M1 (+) cRNA, but not to PB2 and PA. As detected by a luciferase reporter system, let-7c directly targeted the 3'-UTR of M1 (+) cRNA, but not PB2 and PA. To experimentally identify the function of cellular let-7c, precursor let-7c was transfected into A549 cells. Let-7c down-regulated IV M1 expression at both the (+) cRNA and protein levels. Furthermore, transfection with a let-7c inhibitor enhanced the expression of M1. Therefore, let-7c may reduce IV replication by degrading M1 (+) cRNA. This is the first report indicating that cellular miRNA regulates IV replication through the degradation of viral gene (+) cRNA by matching the 3'-UTR of the viral cRNA. These findings suggest that let-7c plays a role in protecting host cells from the virus in addition to its known cellular functions.

Efficacy, safety and immunogenicity of hexavalent rotavirus vaccine in Chinese infants.

A randomized, double-blind, placebo-controlled multicenter trial was conducted in healthy Chinese infants to assess the efficacy and safety of a hexavalent live human-bovine reassortant rotavirus vaccine (HRV) against rotavirus gastroenteritis (RVGE). A total of 6400 participants aged 6-12 weeks were enrolled and randomly assigned to either HRV (n â€‹= â€‹3200) or placebo (n â€‹= â€‹3200) group. All the subjects received three oral doses of vaccine four weeks apart. The vaccine efficacy (VE) against RVGE caused by rotavirus serotypes contained in HRV was evaluated from 14 days after three doses of administration up until the end of the second rotavirus season. VE against severe RVGE, VE against RVGE hospitalization caused by serotypes contained in HRV, and VE against RVGE, severe RVGE, and RVGE hospitalization caused by natural infection of any serotype of rotavirus were also investigated. All adverse events (AEs) were collected for 30 days after each dose. Serious AEs (SAEs) and intussusception cases were collected during the entire study. Our data showed that VE against RVGE caused by serotypes contained in HRV was 69.21% (95%CI: 53.31-79.69). VE against severe RVGE and RVGE hospitalization caused by serotypes contained in HRV were 91.36% (95%CI: 78.45-96.53) and 89.21% (95%CI: 64.51-96.72) respectively. VE against RVGE, severe RVGE, and RVGE hospitalization caused by natural infection of any serotype of rotavirus were 62.88% (95%CI: 49.11-72.92), 85.51% (95%CI: 72.74-92.30) and 83.68% (95%CI: 61.34-93.11). Incidences of AEs from the first dose to one month post the third dose in HRV and placebo groups were comparable. There was no significant difference in incidences of SAEs in HRV and placebo groups. This study shows that this hexavalent reassortant rotavirus vaccine is an effective, well-tolerated, and safe vaccine for Chinese infants.

Small extracellular vesicles derived from human MSCs prevent allergic airway inflammation via immunomodulation on pulmonary macrophages.

Allergic airway inflammation is a major public health disease that affects up to 300 million people in the world. However, its management remains largely unsatisfactory. The dysfunction of pulmonary macrophages contributes greatly to the development of allergic airway inflammation. It has been reported that small extracellular vesicles derived from mesenchymal stromal cells (MSC-sEV) were able to display extensive therapeutic effects in some immune diseases. This study aimed to investigate the effects of MSC-sEV on allergic airway inflammation, and the role of macrophages involved in it. We successfully isolated MSC-sEV by using anion exchange chromatography, which were morphologically intact and positive for the specific EV markers. MSC-sEV significantly reduced infiltration of inflammatory cells and number of epithelial goblet cells in lung tissues of mice with allergic airway inflammation. Levels of inflammatory cells and cytokines in bronchoalveolar lavage fluid were also significantly decreased. Importantly, levels of monocytes-derived alveolar macrophages and M2 macrophages were significantly reduced by MSC-sEV. MSC-sEV were excreted through spleen and liver at 24 h post-administration in mice, and were able to be taken in by macrophages both in vivo and in vitro. In addition, proteomics analysis of MSC-sEV revealed that the indicated three types of MSC-sEV contained different quantities of proteins and shared 312 common proteins, which may be involved in the therapeutic effects of MSC-sEV. In total, our study demonstrated that MSC-sEV isolated by anion exchange chromatography were able to ameliorate Th2-dominant allergic airway inflammation through immunoregulation on pulmonary macrophages, suggesting that MSC-sEV were promising alternative therapy for allergic airway inflammation in the future.

Small extracellular vesicles derived from human mesenchymal stromal cells prevent group 2 innate lymphoid cell-dominant allergic airway inflammation through delivery of miR-146a-5p.

Group 2 innate lymphoid cells (ILC2s) are recently reported to play a more critical role in allergic diseases. We previously identified that mesenchymal stromal cells (MSCs) elicited therapeutic effects on allergic airway inflammation. Small extracellular vesicles (sEV) derived from MSCs possess striking advantages including low immunogenicity and high biosafety, and is extremely promising cell-free therapeutic agents. However, the effects of MSC-sEV on ILC2s are still unclear. Additionally, scalable isolation protocols are required for the mass production of homogenous MSC-sEV especially in clinical application. We previously reported that induced pluripotent stem cells-derived MSCs were the ideal cellular source for the large preparation of MSC-sEV. Here we developed a standardized scalable protocol of anion-exchange chromatography for isolation of MSC-sEV, and investigated the effects of MSC-sEV on ILC2 function from patients with allergic rhinitis and in a mouse ILC2-dominant asthma model. The characterization of MSC-sEV was successfully demonstrated in terms of size, morphology and specific markers. Using flow cytometry and human Cytokine Antibody Array, MSC-sEV but not fibroblasts-sEV (Fb-sEV) were found to significantly inhibit the function of human ILC2s. Similarly, systemic administration of MSC-sEV but not Fb-sEV exhibited an inhibition of ILC2 levels, inflammatory cell infiltration and mucus production in the lung, a reduction in levels of T helper 2 cytokines, and alleviation of airway hyperresponsiveness in a mouse model of asthma. Using RNA sequencing, miR-146a-5p was selected as the candidate to mediate the above effects of MSC-sEV. We next revealed the uptake of ILC2s to MSC-sEV, and that transfer of miR-146a-5p in MSC-sEV to ILC2s in part contributed to the effects of MSC-sEV on ILC2s in vitro and in a mouse model. In conclusion, we demonstrated that MSC-sEV were able to prevent ILC2-dominant allergic airway inflammation at least partially through miR-146a-5p, suggesting that MSC-sEV could be a novel cell-free strategy for the treatment of allergic diseases.

Mesenchymal stem cells for inflammatory airway disorders: promises and challenges.

The regenerative and immunomodulatory characteristics of mesenchymal stem cells (MSCs) make them attractive in the treatment of many diseases. Although they have shown promising preclinical studies of immunomodulation and paracrine effects in inflammatory airway disorders and other lung diseases, there are still challenges that have to be overcome before MSCs can be safely, effectively, and routinely applied in the clinical setting. A good understanding of the roles and mechanisms of the MSC immunomodulatory effects will benefit the application of MSC-based clinical therapy. In this review, we summarize the promises and challenges of the preclinical and clinical trials of MSC therapies, aiming to better understand the role that MSCs play in attempt to treat inflammatory airway disorders.

Human pluripotent stem cell-derived mesenchymal stem cells prevent chronic allergic airway inflammation via TGF-ß1-Smad2/Smad3 signaling pathway in mice.

BACKGROUND: Asthma is a chronic disease involving inflamed airways, which were previously demonstrated, can be modulated by the mesenchymal stem cells derived from induced pluripotent stem cells (iPSC-MSCs). However, the long-term effects of iPSC-MSCs in inflamed airways are still unidentified. This study investigated the long-term effects and potential mechanisms involved in the immunomodulatory effects of iPSC-MSCs in the chronic mouse asthma model. METHODS: Both human iPSC-MSCs and bone marrow (BM)-MSCs were transplanted into the long-term ovalbumin-induced mice before sensitization phase or during the challenge phase. Airway hyper-respnsiveness measurement, immunohistochemistry and ELISA were employed to assess the effects of MSCs. In addition, Smad2/3 levels were assessed by western blot analysis to investigate the possible mechanism involved. RESULTS: The systemic administration of human iPSC-MSCs before the challenge protected the mice from the characters of the chronic allergic airway inflammation, in particular improving the airway remodeling and preventing fibrosis. In addition, the TGF-ß1/Smad pathway was identified involved in the immunomodulatory effects of iPSC-MSCs on chronic allergic airway inflammation. CONCLUSIONS: The study demonstrated that iPSC-MSCs are capable of preventing chronic allergic airway inflammation over a prolonged period, which further proved the iPSC-MSC therapeutic potential for allergic airway inflammation in a clinical scenario.

Reciprocal Regulation Between O-GlcNAcylation and ß-Catenin Facilitates Cell Viability and Inhibits Apoptosis in Liver Cancer.

Abnormal expression of O-Linked ß-N-acetylglucosamine (O-GlcNAc) and ß-catenin is a general feature of cancer and contributes to transformed phenotypes. In this study, we identified the interaction between O-GlcNAc and ß-catenin, and explored their effects on the progression of liver cancer. Our results demonstrated that upregulation of O-GlcNAc was induced by high glucose, whereas the application of PuGNAc and GlcNAc increased ß-catenin protein expression levels, as well as the protein's stability and nuclear accumulation in the liver cancer cell lines HEP-G2 and HuH-7. In addition, overexpression of ß-catenin could increase O-GlcNAc expression levels through upregulation of uridine 5'-diphosphate (UDP)-N-acetylglucosamine pyrophosphorylase 1 (UAP1) protein expression, protein stability, and inhibition of its ubiquitination. Moreover, the O-GlcNAcylation of ß-catenin promoted the proliferation, colony formation, and repressed the induction of apoptosis in HEP-G2 and HuH-7 cells. Knockdown of ß-catenin reduced cell proliferation, colony formation, and tumorigenesis, and promoted cell apoptosis through the downregulation of UAP1 expression. In conclusion, this study revealed that the reciprocal regulation between O-GlcNAcylation and ß-catenin facilitated the proliferation of liver cancer.

An in Vitro and in Vivo Study of the Effect of Dexamethasone on Immunoinhibitory Function of Induced Pluripotent Stem Cell-Derived Mesenchymal Stem Cells.

Induced pluripotent stem cell-derived mesenchymal stem cells (iPSC-MSCs) represent a promising cell source for patient-specific cell therapy. We previously demonstrated that they display an immunomodulatory effect on allergic airway inflammation. Glucocorticoids are powerful anti-inflammatory compounds and widely used in the therapy of allergic diseases. However, the effect of glucocorticoids on the immunomodulatory function of iPSC-MSCs remains unknown. This study aimed to determine the effect of dexamethasone (Dex) on the immunomodulatory function of iPSC-MSCs in vitro and in vivo. A total of three human iPSC-MSC clones were generated from amniocyte-derived iPSCs. Anti-CD3/CD28-induced peripheral blood mononuclear cell (PBMC) proliferation was used to assess the effect of Dex on the immunoinhibitory function of iPSC-MSCs in vitro. Mouse models of contact hypersensitivity (CHS) and allergic airway inflammation were induced, and the levels of inflammation in mice were analyzed with the treatments of iPSC-MSCs and Dex, alone and combined. The results showed that Dex did not interfere with the immunoinhibitory effect of iPSC-MSCs on PBMC proliferation. In CHS mice, simultaneous treatment with Dex did not affect the effect of iPSC-MSCs on the inflammation, both in regional draining lymph nodes and in inflamed ear tissue. In addition, co-administration of iPSC-MSCs with Dex decreased the local expression of interferon (IFN)-γ and tumor necrosis factor (TNF)-α in the ears of CHS mice. In the mouse model of allergic airway inflammation, iPSC-MSC treatment combined with Dex resulted in a similar extent of reduction in pulmonary inflammation as iPSC-MSCs or Dex treatment alone. In conclusion, Dex does not significantly affect the immunomodulatory function of iPSC-MSCs both in vitro and in vivo. These findings may have implications when iPSC-MSCs and glucocorticoids are co-administered.