Clinical significance of changes in the Th17/Treg ratio in autoimmune liver disease

Approaches for Performance Verification Toward Standardization of Peripheral Blood Regulatory T-Cell Detection by Flow Cytometry

CONTEXT.—

Regulatory T-cell (Treg) detection in peripheral blood, based on flow cytometry, is invaluable for diagnosis and treatment of immune-mediated diseases. However, there is a lack of reliable methods to verify the performance, which is pivotal toward standardization of the Tregs assay.

OBJECTIVE.—

To conduct standardization studies and verify the performance of 3 commercially available reagent sets for the Tregs assay based on flow cytometry and agreement analysis for Treg detection across the different reagent sets.

DESIGN.—

The analytical performance of Tregs assay using reagent sets supplied by 3 manufacturers was evaluated after establishing the gating strategy and determining the optimal antibody concentration. Postcollection sample stability was evaluated, as well as the repeatability, reproducibility, reportable range, linearity, and assay carryover. Agreement between the different assays was assessed via Bland-Altman plots and linear regression analysis. The relationship between the frequency of CD4+CD25+CD127low/- Tregs and CD4+CD25+Foxp3+ Tregs was evaluated.

RESULTS.—

The postcollection sample stability was set at 72 hours after collection at room temperature. The accuracy, repeatability, reproducibility, and accuracy all met the requirements for clinical analysis. Excellent linearity, with R2 ≥0.9 and no assay carryover, was observed. For reportable range, a minimum of 1000 events in the CD3+CD4+ gate was required for Tregs assay. Moreover, the results for Tregs labeled by antibodies from the 3 manufacturers were in good agreement. The percentage of CD4+CD25+CD127low/- Tregs was closely correlated with CD4+CD25+Foxp3+ Tregs.

CONCLUSIONS.—

This is the first study to evaluate systematically the measurement performance of Tregs in peripheral blood by flow cytometry, which provides a practical solution to verifying the performance of flow cytometry-based immune monitoring projects in clinical practice.

Advances in the study of artemisinin and its derivatives for the treatment of rheumatic skeletal disorders, autoimmune inflammatory diseases, and autoimmune disorders: a comprehensive review

Artemisinin and its derivatives are widely recognized as first-line treatments for malaria worldwide. Recent studies have demonstrated that artemisinin-based antimalarial drugs, such as artesunate, dihydroartemisinin, and artemether, not only possess excellent antimalarial properties but also exhibit antitumor, antifungal, and immunomodulatory effects. Researchers globally have synthesized artemisinin derivatives like SM735, SM905, and SM934, which offer advantages such as low toxicity, high bioavailability, and potential immunosuppressive properties. These compounds induce immunosuppression by inhibiting the activation of pathogenic T cells, suppressing B cell activation and antibody production, and enhancing the differentiation of regulatory T cells. This review summarized the mechanisms by which artemisinin and its analogs modulate excessive inflammation and immune responses in rheumatic and skeletal diseases, autoimmune inflammatory diseases, and autoimmune disorders, through pathways including TNF, Toll-like receptors, IL-6, RANKL, MAPK, PI3K/AKT/mTOR, JAK/STAT, and NRF2/GPX4. Notably, in the context of the NF-κB pathway, artemisinin not only inhibits NF-κB expression by disrupting upstream cascades and/or directly binding to NF-κB but also downregulates multiple downstream genes controlled by NF-κB, including inflammatory chemokines and their receptors. These downstream targets regulate various immune cell functions, apoptosis, proliferation, signal transduction, and antioxidant responses, ultimately intervening in systemic autoimmune diseases and autoimmune responses in organs such as the kidneys, nervous system, skin, liver, and biliary system by modulating immune dysregulation and inflammatory responses. Ongoing multicenter randomized clinical trials are investigating the effects of these compounds on rheumatic, inflammatory, and autoimmune diseases, with the aim of translating promising preclinical data into clinical applications.

Ongoing involvers and promising therapeutic targets of hepatic fibrosis: The hepatic immune microenvironment

Hepatic fibrosis is often secondary to chronic inflammatory liver injury. During the development of hepatic fibrosis, the damaged hepatocytes and activated hepatic stellate cells (HSCs) caused by the pathogenic injury could secrete a variety of cytokines and chemokines, which will chemotactic innate and adaptive immune cells of liver tissue and peripheral circulation infiltrating into the injury site, mediating the immune response against injury and promoting tissue reparation. However, the continuous release of persistent injurious stimulus-induced inflammatory cytokines will promote HSCs-mediated fibrous tissue hyperproliferation and excessive repair, which will cause hepatic fibrosis development and progression to cirrhosis even liver cancer. And the activated HSCs can secrete various cytokines and chemokines, which directly interact with immune cells and actively participate in liver disease progression. Therefore, analyzing the changes in local immune homeostasis caused by immune response under different pathological states will greatly enrich our understanding of liver diseases' reversal, chronicity, progression, and even deterioration of liver cancer. In this review, we summarized the critical components of the hepatic immune microenvironment (HIME), different sub-type immune cells, and their released cytokines, according to their effect on the development of progression of hepatic fibrosis. And we also reviewed and analyzed the specific changes and the related mechanisms of the immune microenvironment in different chronic liver diseases.Moreover, we retrospectively analyzed whether the progression of hepatic fibrosis could be alleviated by modulating the HIME.We aimed to elucidate the pathogenesis of hepatic fibrosis and provide the possibility for exploring the therapeutic targets for hepatic fibrosis.

Differential expression of CCR8 in tumors versus normal tissue allows specific depletion of tumor-infiltrating T regulatory cells by GS-1811, a novel Fc-optimized anti-CCR8 antibody

The presence of T regulatory (Treg) cells in the tumor microenvironment is associated with poor prognosis and resistance to therapies aimed at reactivating anti-tumor immune responses. Therefore, depletion of tumor-infiltrating Tregs is a potential approach to overcome resistance to immunotherapy. However, identifying Treg-specific targets to drive such selective depletion is challenging. CCR8 has recently emerged as one of these potential targets. Here, we describe GS-1811, a novel therapeutic monoclonal antibody that specifically binds to human CCR8 and is designed to selectively deplete tumor-infiltrating Tregs. We validate previous findings showing restricted expression of CCR8 on tumor Tregs, and precisely quantify CCR8 receptor densities on tumor and normal tissue T cell subsets, demonstrating a window for selective depletion of Tregs in the tumor. Importantly, we show that GS-1811 depleting activity is limited to cells expressing CCR8 at levels comparable to tumor-infiltrating Tregs. Targeting CCR8 in mouse tumor models results in robust anti-tumor efficacy, which is dependent on Treg depleting activity, and synergizes with PD-1 inhibition to promote anti-tumor responses in PD-1 resistant models. Our data support clinical development of GS-1811 to target CCR8 in cancer and drive tumor Treg depletion in order to promote anti-tumor immunity.

Identification of an immune-related gene prognostic index for predicting prognosis, immunotherapeutic efficacy, and candidate drugs in amyotrophic lateral sclerosis

Rationale and objectives

Considering the great insufficiency in the survival prediction and therapy of amyotrophic lateral sclerosis (ALS), it is fundamental to determine an accurate survival prediction for both the clinical practices and the design of treatment trials. Therefore, there is a need for more accurate biomarkers that can be used to identify the subtype of ALS which carries a high risk of progression to guide further treatment.

Methods

The transcriptome profiles and clinical parameters of a total of 561 ALS patients in this study were analyzed retrospectively by analysis of four public microarray datasets. Based on the results from a series of analyses using bioinformatics and machine learning, immune signatures are able to be used to predict overall survival (OS) and immunotherapeutic response in ALS patients. Apart from other comprehensive analyses, the decision tree and the nomogram, based on the immune signatures, were applied to guide individual risk stratification. In addition, molecular docking methodology was employed to screen potential small molecular to which the immune signatures might response.

Results

Immune was determined as a major risk factor contributing to OS among various biomarkers of ALS patients. As compared with traditional clinical features, the immune-related gene prognostic index (IRGPI) had a significantly higher capacity for survival prediction. The determination of risk stratification and assessment was optimized by integrating the decision tree and the nomogram. Moreover, the IRGPI may be used to guide preventative immunotherapy for patients at high risks for mortality. The administration of 2MIU IL2 injection in the short-term was likely to be beneficial for the prolongment of survival time, whose dosage should be reduced to 1MIU if the long-term therapy was required. Besides, a useful clinical application for the IRGPI was to screen potential compounds by the structure-based molecular docking methodology.

Conclusion

Ultimately, the immune-derived signatures in ALS patients were favorable biomarkers for the prediction of survival probabilities and immunotherapeutic responses, and the promotion of drug development.

Human liver stem cells alleviate Con-A induced liver injury by regulating the balance of Treg/Th17 cells

BACKGROUND

Liver injury is a serious threat to human health that has become a worldwide problem. To date, there is still no effective treatment strategy. In the present study, we examined the protective effects of Human liver stem cells (HLSCs) against concanavalin A (Con A)-induced acute liver injury.

METHODS

Isolated HLSCs were characterized by microscopy, functional assays, and gene expression. HLSCs or HLSCs culture medium were transplanted in mice for 12 h and subsequently challenged with Con A via tail-vein injection. The effects were evaluated through survival rate, histology, blood tests, TUNEL assay, quantitative RT-PCR and flow cytometry. CellTracker™ CM-Dil labled HLSCs were tracked by fluorescence microscope.

RESULTS

Transplantation of HLSCs reduced the mortality rate, reduced the levels of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and total bilirubin (TBIL), narrowed the area of liver necrosis, and inhibited hepatocyte apoptosis induced by Con A. Injection of HLSCs culture medium could also alleviate Con A-induced liver injury. Of note, HLSCs-transplanted mice exhibited lower frequencies of Th17 cells and higher frequencies of Tregs in their liver and spleen following Con A injection. Moreover, transplantation of HLSCs significantly reduced the expression of IL-17A, IL-17F and ROR-γt induced by Con A, while reversed Con A-induced downregulation of Foxp3 expression and IL-10.

CONCLUSIONS

HLSCs protect mice from immune-mediated liver injury by regulating the balance of Treg/Th17 cells, suggesting that transplantation of HLSCs is a potential and effective therapeutic method for amelioration of liver injury.

CHI3L1 alleviate acute liver injury by inhibiting Th1 cells differentiation through STAT3 signaling pathway

Background

Acute liver injury (ALI) is a severe liver disease. Chitinase 3-like-1 (CHI3L1), a protein belonging to the glycosyl hydrolase family 18, is involved in many diseases, such as inflammatory diseases, bacterial infections, and various malignant tumors; however, the function of CHI3L1 in ALI remains unclear. The objective of this study was to evaluate the protective functions of CHI3L1 against thioacetamide (TAA)-induced ALI in mice and explore its potential mechanisms.

Methods

Data from 20 patients with ALI and 10 healthy subjects was collected. Serum CHI3L1, serum aspartate transaminase (AST), and serum alanine aminotransferase (ALT) were measured. To establish ALI mouse models, thioacetamide was intraperitoneally injected into groups of the CHI3L1-knockout (CHI3L1-KO) and wild-type (WT) mice (80 and 150 mg/kg). Recombinant CHI3L1 protein (rCHI3L1) (5 µg/kg), IFN-γ (500 ng), and WP1033 (an inhibitor of P-STAT3, 0.2 mL) were injected before TAA treatment, after which the effects were estimated. Splenic CD4+CD62L+ naive T cells were isolated from CHI3L1-KO mice and stimulated to differentiate into regulatory T (Treg) cells, T-helper 1 (Th1) cells, T-helper 2 (Th2) cells, and T-helper 17 (Th17) cells.

Results

Increased serum CHI3L1 levels were seen both in healthy subjects and post-therapy patients compared with ALI patients. CHI3L1 levels were negatively correlated with serum ALT and AST levels in ALI patients. CHI3L1-KO group showed higher serum ALT and AST levels than the WT group following TAA treatment, while tail vein injection of rCHI3L1 reduced liver tissue injury and improved Treg cell differentiation in vivo. In vitro experiment showed that knockout of CHI3L1 improved IFN-γ+ Th1 cell differentiation. Furthermore, intraperitoneal administration of IFN-γ produced more severe hepatocellular necrosis compared with rCHI3L1 injection alone. Mechanism study showed that T-box expressed in T cells (T-bet), and signal transducer and activator of transcription 3 (STAT3), play a critical role in adversely mediating the effect of CHI3L1, which is consistent with the finding that treatment with WP1033 down-regulated the differentiation of the Th1 cells in vitro and reduced severity of liver injury in vivo.

Conclusions

CHI3L1 reduced the production of IFN-γ and inhibited Th1 cell differentiation through the STAT3 signaling pathway, which could be a potential therapeutic strategy for treating ALI.

The role of the CD39-CD73-adenosine pathway in liver disease

Extracellular adenosine triphosphate (ATP) is a danger signal released by dying and damaged cells, and it functions as an immunostimulatory signal that promotes inflammation. The ectonucleotidases CD39/ectonucleoside triphosphate diphosphohydrolase-1 and CD73/ecto-5'-nucleotidase are cell-surface enzymes that breakdown extracellular ATP into adenosine. This drives a shift from an ATP-driven proinflammatory environment to an anti-inflammatory milieu induced by adenosine. The CD39-CD73-adenosine pathway changes dynamically with the pathophysiological context in which it is embedded. Accumulating evidence suggests that CD39 and CD73 play important roles in liver disease as critical components of the extracellular adenosinergic pathway. Recent studies have shown that the modification of the CD39-CD73-adenosine pathway alters the liver's response to injury. Moreover, adenosine exerts different effects on the pathophysiology of the liver through different receptors. In this review, we aim to describe the role of the CD39-CD73-adenosine pathway and adenosine receptors in liver disease, highlighting potential therapeutic targets in this pathway, which will facilitate the development of therapeutic strategies for the treatment of liver disease.

Effect of peripheral blood-derived mesenchymal stem cells on macrophage polarization and Th17/Treg balance in vitro

Introduction

Mesenchymal stem cells (MSCs) have always been the center of the experimental exploration of regenerative therapy together with other stem cells. Among with, peripheral blood-derived mesenchymal stem cells (PBMSCs) have been regarded as promising in clinical applications for its convenience of acquisition from peripheral blood. However, few reported experiments so far to elucidate the exact mechanisms of how PBMSC influence regeneration. As the ability of immunomodulatory is one of the crucial features that influence MSC to reconstruct impaired tissue, we decided to focus on the immunomodulatory abilities of PBMSCs and conducted experiments associated with macrophages and T lymphocytes, which are two main cell types that dominate the innate and acquired immunity. Therefore, a basis can be made from these experiments for applications of PBMSCs in regenerative therapy in the future.

Methods

A Transwell system was used for the coculturing of PBMSCs with macrophages. T lymphocytes were cultured directly with PBMSCs. Flow cytometry and immunochemistry were conducted for identifying the phenotypes. Immunomagnetic microspheres, ELISA and RT-qPCR were used to detect the expressions of relevant molecules or mRNAs.

Results

After coculturing PBMSCs with M0, the anti-inflammatory IL-10 was increased whereas the proinflammatory TNF-α decreased; the expression of CD11b, CD68, CD206, Arg-1, IL-10 and CCL-22 was up-regulated whereas IL-1β down-regulated. The expression of TGF-β, RORγt, Foxp3 and IL-10 was increased in the cocultured lymphocytes whereas IL-17 and IL-6 decreased; the ratio of CD4⁺IL-17⁺ Th17/CD25⁺Foxp3⁺ Treg was reduced.

Conclusion

The findings demonstrated that PBMSCs promoted the anti-inflammatory features of macrophages and the Th17/Treg system. PBMSCs are able to inhibit inflammation associated with these two immune cell systems, and thus provide insight into how PBMSCs achieve their immunomodulatory ability.

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Anti-inflammatory effect of peripheral blood-derived mesenchymal stem cells.

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Co-culture promotes the polarization of M2 macrophages.

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Co-culture alters the balance of Th17/Tregs.

Gut-Liver Physiomimetics Reveal Paradoxical Modulation of IBD-Related Inflammation by Short-Chain Fatty Acids

Although the association between the microbiome and IBD and liver diseases is known, the cause and effect remain elusive. By connecting human microphysiological systems of the gut, liver, and circulating Treg and Th17 cells, we created a multi-organ model of ulcerative colitis (UC) ex vivo. The approach shows microbiome-derived short-chain fatty acids (SCFAs) to either improve or worsen UC severity, depending on the involvement of effector CD4 T cells. Using multiomics, we found SCFAs increased production of ketone bodies, glycolysis, and lipogenesis, while markedly reducing innate immune activation of the UC gut. However, during acute T cell-mediated inflammation, SCFAs exacerbated CD4⁺ T cell-effector function, partially through metabolic reprograming, leading to gut barrier disruption and hepatic injury. These paradoxical findings underscore the emerging utility of human physiomimetic technology in combination with systems immunology to study causality and the fundamental entanglement of immunity, metabolism, and tissue homeostasis.

Transplanted mouse liver stem cells at different stages of differentiation ameliorate concanavalin A-induced acute liver injury by modulating Tregs and Th17 cells in mice

Acute liver failure (ALF) is a disease with a considerably high mortality rate that still lacks a safe and effective treatment. Transplantation of liver stem cells (LSCs) has been considered to be a promising therapeutic alternative for ALF since LSCs have been shown to be involved in immunomodulation and functional reconstruction of the liver. Our present study evaluated and compared the protective effects of the two mouse LSC lines, YE and R5, as well as those of adult mouse hepatocyte (HC), on concanavalin A (ConA)-induced acute liver injury. YE and R5 cells were analyzed by microscopy, functional assays, and gene expression. We confirmed that YE and R5 cells were undifferentiated cells that had partial hepatocytic functions and a potential to differentiate into hepatocytes. YE cells has characteristics of LSCs at the early stage of differentiation, whereas the differentiation stage of R5 cells was later than that of YE cells. Subsequently, YE, R5, and HC cells were intraperitoneally transplanted into three groups of mice, followed by injection of ConA through the tail vein of each mouse at 12 h later. Blood tests, histology, flow cytometry, and quantitative PCR were then used to evaluate the therapeutic effects of the cell transplantations at 24 h after ConA injections. Compared with that of the ConA control group, YE, R5, and HC cells reduced the expression of alanine transaminase (ALT), aspartate aminotransferase (AST), and total bilirubin (TBIL) in serum and alleviated the degree of hepatic necrosis. Moreover, transplantation of these cells induced more regulatory T cells (Tregs) and less T-helper 17 (Th17) cells in the liver and spleen, and also promoted the expression of forkhead box protein 3 (Foxp3) and interleukin (IL)-10; in contrast, these transplantations induced various degrees of inhibition in the expression of retinoic acid-related orphan receptor γt (RORγt), IL-17A, IL-17F, and tumor necrosis factor-α (TNF-α). The protective effects of YE and R5 cells were significantly stronger than those of HC cells, and YE cells at the earlier differentiation stage than that of R5 cells exhibited the strongest protective effects. These results demonstrate that mouse LSCs at different stages of differentiation alleviate ConA-induced acute liver injury in mice by modulating Tregs, Th17 cells, and cytokine secretion.

IL-17 and IL-17-producing cells and liver diseases, with focus on autoimmune liver diseases

The pro-inflammatory cytokine interleukin(IL)-17 and IL-17-producing cells are important players in the pathogenesis of many autoimmune / inflammatory diseases. More recently, they have been associated with liver diseases. This review first describes the general knowledge on IL-17 and IL-17 producing cells. The second part describes the in vitro and in vivo effects of IL-17 on liver cells and the contribution of IL-17 producing cells to liver diseases. IL-17 induces immune cell infiltration and liver damage driving to hepatic inflammation and fibrosis and contributes to autoimmune liver diseases. The circulating levels of IL-17 and the frequency of IL-17-producing cells are elevated in a variety of acute and chronic liver diseases. The last part focuses on the effects of IL-17 deletion or neutralization in various murine models. Some of these observed beneficial effects suggest that targeting the IL-17 axis could be a new therapeutic strategy to prevent chronicity and progression of various liver diseases.