Scutellarein Ameliorated Chondrocyte Inflammation and Osteoarthritis in Rats.

OBJECTIVE: Osteoarthritis (OA) is a degenerative joint disorder characterized by the gradual degradation of joint cartilage and local inflammation. This study aimed to investigate the anti-OA effect of scutellarein (SCU), a single-unit flavonoid compound obtained from Scutellaria barbata D. Don, in rats. METHODS: The extracted rat chondrocytes were treated with SCU and IL-1ß. The chondrocytes were divided into control group, IL-1ß group, IL-1ß+SCU 50 µmol/L group, and IL-1ß+SCU 100 µmol/L group. Morphology of rat chondrocytes was observed by toluidine blue and safranin O staining. CCK-8 method was used to detect the cytotoxicity of SCU. ELISA, qRT-PCR, Western blotting, immunofluorescence, SAß-gal staining, flow cytometry, and bioinformatics analysis were applied to evaluate the effect of SCU on rat chondrocytes under IL-1ß intervention. Additionally, anterior cruciate ligament transection (ACL-T) was used to establish a rat OA model. Histological changes were detected by safranin O/fast green, hematoxylin-eosin (HE) staining, and immunohistochemistry. RESULTS: SCU protected cartilage and exhibited anti-inflammatory effects via multiple mechanisms. Specifically, it could enhance the synthesis of extracellular matrix in cartilage cells and inhibit its degradation. In addition, SCU partially inhibited the nuclear factor kappa-B/mitogen-activated protein kinase (NF-κB/MAPK) pathway, thereby reducing inflammatory cytokine production in the joint cartilage. Furthermore, SCU significantly reduced IL-1ß-induced apoptosis and senescence in rat chondrocytes, further highlighting its potential role in OA treatment. In vivo experiments revealed that SCU (at a dose of 50 mg/kg) administered for 2 months could significantly delay the progression of cartilage damage, which was reflected in a lower Osteoarthritis Research Society International (OARSI) score, and reduced expression of matrix metalloproteinase 13 (MMP13) in cartilage. CONCLUSION: SCU is effective in the therapeutic management of OA and could serve as a potential candidate for future clinical drug therapy for OA.

Targeting pathogenic CD8+ tissue-resident T cells with chimeric antigen receptor therapy in murine autoimmune cholangitis.

Primary biliary cholangitis (PBC) is a cholestatic autoimmune liver disease characterized by autoreactive T cell response against intrahepatic small bile ducts. Here, we use Il12b-/-Il2ra-/- mice (DKO mice) as a model of autoimmune cholangitis and demonstrate that Cd8a knockout or treatment with an anti-CD8α antibody prevents/reduces biliary immunopathology. Using single-cell RNA sequencing analysis, we identified CD8+ tissue-resident memory T (Trm) cells in the livers of DKO mice, which highly express activation- and cytotoxicity-associated markers and induce apoptosis of bile duct epithelial cells. Liver CD8+ Trm cells also upregulate the expression of several immune checkpoint molecules, including PD-1. We describe the development of a chimeric antigen receptor to target PD-1-expressing CD8+ Trm cells. Treatment of DKO mice with PD-1-targeting CAR-T cells selectively depleted liver CD8+ Trm cells and alleviated autoimmune cholangitis. Our work highlights the pathogenic role of CD8+ Trm cells and the potential therapeutic usage of PD-1-targeting CAR-T cells.

Lymphatic endothelial cell-mediated accumulation of CD177+Treg cells suppresses antitumor immunity in human esophageal squamous cell carcinoma.

Regulatory T (Treg) cells are critical in shaping an immunosuppressive microenvironment to favor tumor progression and resistance to therapies. However, the heterogeneity and function of Treg cells in esophageal squamous cell carcinoma (ESCC) remain underexplored. We identified CD177 as a tumor-infiltrating Treg cell marker in ESCC. Interestingly, expression levels of CD177 and PD-1 were mutually exclusive in tumor Treg cells. CD177+ Treg cells expressed high levels of IL35, in association with CD8+ T cell exhaustion, whereas PD-1+ Treg cells expressed high levels of IL10. Pan-cancer analysis revealed that CD177+ Treg cells display increased clonal expansion compared to PD-1+ and double-negative (DN) Treg cells, and CD177+ and PD-1+ Treg cells develop from the same DN Treg cell origin. Importantly, we found CD177+ Treg cell infiltration to be associated with poor overall survival and poor response to anti-PD-1 immunotherapy plus chemotherapy in ESCC patients. Finally, we found that lymphatic endothelial cells are associated with CD177+ Treg cell accumulation in ESCC tumors, which are also decreased after anti-PD-1 immunotherapy plus chemotherapy. Our work identifies CD177+ Treg cell as a tumor-specific Treg cell subset and highlights their potential value as a prognostic marker of survival and response to immunotherapy and a therapeutic target in ESCC.

MiR-3074-5p Regulates Trophoblasts Function via EIF2S1/GDF15 Pathway in Recurrent Miscarriage.

Dysfunction of extravillous trophoblasts (EVTs) might cause early pregnancy failure by interfering with embryo implantation and/or placentation. We previously reported that the villus miR-3074-5p expression level was increased, whereas the peripheral level of GDF15, a predict target gene of miR-3074-5p, was decreased in recurrent miscarriages (RM) patients, and miR-3074-5p could enhance apoptosis but reduce invasion of human extravillous trophoblast cells (EVTs). The aim of this study was to further explore roles of miR-3074-5p/GDF15 pathway in regulation of EVTs function. It was validated that GDF15 was not the direct target of miR-3074-5p, whereas EIF2S1, an upstream regulator of GDF15 maturation and secretion, was the direct target of miR-3074-5p. The villus expression levels of GDF15 and EIF2S1 were significantly decreased in RM patients. Knockdown of GDF15 expression presented inhibitory effects on proliferation, migration, and invasion of HTR8/SVneo cells. Up-regulated miR-3074-5p expression led to the significant decreased GDF15 expression in HTR8/SVneo cells, and this effect could be efficiently reversed by the overexpression of EIF2S1. Meanwhile, the suppressive effects of miR-3074-5p on proliferation, migration, and invasion of HTR8/SVneo cells could be intercepted by the treatment of recombinant human GDF15 protein. Collectively, these data suggested that miR-3074-5p could reduce GDF15 production via targeting inhibition of EIF2S1 expression, and the deficiency in GDF15 function might lead to the early pregnancy loss by attenuating proliferation and invasion of EVTs.

Symptom burden survey and symptom clusters in patients with cervical cancer: a cross-sectional survey.

PURPOSE: The purpose of this study is to determine the incidence and severity of symptoms of patients with cervical cancer within 6 months after radiotherapy and chemotherapy, form a symptom burden report, evaluate the distribution characteristics of symptoms, identify symptom clusters, and provide a basis for clinical doctors and nurses to improve the symptom management of patients with cervical cancer after radiotherapy and chemotherapy. METHODS: The patients with cervical cancer within 6 months after radiotherapy and chemotherapy were recruited to investigate their symptom burden. Exploratory factor analysis was used to identify symptom clusters. RESULTS: A total of 250 patients participated in the study. The study found that the most common symptom among the 40 symptoms was fatigue, and the most serious symptom was nocturia. Based on the occurrence rate and severity of symptoms, nine symptom clusters were identified, including psycho-emotion-related symptom cluster, pain-disturbed sleep-related symptom cluster, menopausal symptom cluster, tinnitus-dizziness-related symptom cluster, urinary-related symptom cluster, dry mouth-bitter taste-related symptom cluster, intestinal-related symptom cluster, memory loss-numbness-related symptom cluster, and emaciation-related symptom cluster. The three most serious symptom clusters are pain-disturbed sleep-related symptom cluster, urinary-related symptom cluster, and memory loss-numbness-related symptom cluster. CONCLUSION: The symptoms of patients with cervical cancer within 6 months after radiotherapy and chemotherapy are complex, and nine symptom clusters can be identified according to the incidence and severity of symptoms. We can find the potential biological mechanism of each symptom cluster through the discussion of previous mechanism research and clinical research. The number of symptom clusters and the number of symptoms within the symptom cluster are closely related to the symptom evaluation scale selected for the study. Therefore, the symptom cluster study urgently needs a targeted symptom evaluation scale that can comprehensively reflect the patient's condition.

A ratiometric fluorescent probe for fast detection and bioimaging of formaldehyde.

A novel ratiometric probe (SWJT-10) based on isophorone derivatives has been designed and synthesized for the detection of formaldehyde (FA). This probe displayed an obvious ratiometric fluorescence response to FA with a blue shift from the NIR (680 nm) to the yellow light region (600 nm) in aqueous solution. And it showed good selectivity, high sensitivity and a fast response to FA (less than 5 s) due to a new recognition mechanism. Moreover, SWJT-10 has been applied to monitor FA in living cells and zebrafish.

The gut microbiome contributes to splenomegaly and tissue inflammation in a murine model of primary biliary cholangitis.

Background: Splenomegaly is not just a consequence of numerous chronic and acute conditions but may also contribute to their severity, due to the interaction of the spleen with the gut microbiome. This study aimed to explore the effect of the gut microbiome on splenomegaly. Methods: We used p40-/-IL-2Rα-/- mice as a murine model of primary biliary cholangitis (PBC) as per our previous study. Splenomegaly was evaluated by spleen weight. Severity of liver inflammation was evaluated by hepatic mononuclear cell (MNCs) number and pathological score. Changes of immune cells in the spleen and liver were detected by flow cytometry. The effects of the gut microbiome on splenomegaly and liver inflammation were observed by combined antibiotic treatment in p40-/-IL-2Rα-/- mice. Results: A proportion of p40-/-IL-2Rα-/- mice developed splenomegaly. The results revealed that liver mononuclear cells infiltration, histological scores of hepatic inflammation, and bile duct damage were positively correlated with the degree of splenomegaly. Hepatic CD4+ and CD8+ T cells numbers were significantly higher in mice with splenomegaly, and this was particularly observed in activated effector memory CD4+ T and CD8+ T cells. A proportion of some other immune cells including granulocytes, B, natural killer (NK), and CD8+ T effector memory cells were also altered in the enlarged spleen. More importantly, administration of quadruple antibiotics to deplete gut microbiota relieved the splenomegaly of p40-/-IL-2Rα-/- mice, significantly alleviated liver inflammation, and caused a significant reduction of liver and spleen T cell accumulation and activation; however, single antibiotics did not induce these changes. Conclusions: Splenomegaly was associated with more severe liver inflammation in our PBC murine model, and this effect was reversed by quadruple antibiotic treatment.

The Proinflammatory Cytokines IL-18, IL-21, and IFN-γ Differentially Regulate Liver Inflammation and Anti-Mitochondrial Antibody Level in a Murine Model of Primary Biliary Cholangitis.

Primary biliary cholangitis (PBC) is a cholestatic liver disease primarily featured by autoimmune-mediated damage of intrahepatic small- and medium-sized bile ducts. Elevated serum proinflammatory cytokines, serum anti-mitochondrial antibodies (AMAs), liver inflammation, and fibrosis are also hallmarks of PBC disease. However, whether the elevated proinflammatory cytokines play a role in autoimmune cholangitis remains unknown. Herein, we utilized the p40-/-IL-2Rα -/- PBC mouse model to investigate the roles of proinflammatory cytokines IL-18, IL-21, and IFN-γ in the onset and progression of PBC. IL-18-/-, IFN-γ -/-, and IL-21-/- mice were crossed with p40-/-IL-2Ra+/- mice, respectively, to produce corresponding cytokine-deficient PBC models. Autoantibody level, liver inflammation, and bile duct injury were analyzed. We found that livers from p40-/-IL-2Rα -/- mice exhibit similar transcriptomic characters of PBC patients. In p40-/-IL-2Rα -/- mice, deletion of IL-18 has no remarkable effect on disease progression, while deletion of IL-21 indicates that it is necessary for AMA production but independent of liver inflammation and cholangitis. IFN-γ is responsible for both AMA production and liver inflammation in our model. Our results demonstrate that different proinflammatory cytokines can regulate different effector functions in PBC pathogenesis and need to be considered in PBC treatment.

Chromatin accessibility analysis identifies the transcription factor ETV5 as a suppressor of adipose tissue macrophage activation in obesity.

Activation of adipose tissue macrophages (ATMs) contributes to chronic inflammation and insulin resistance in obesity. However, the transcriptional regulatory machinery involved in ATM activation during the development of obesity is not fully understood. Here, we profiled the chromatin accessibility of blood monocytes and ATMs from obese and lean mice using assay for transposase-accessible chromatin sequencing (ATAC-seq). We found that monocytes and ATMs from obese and lean mice exhibited distinct chromatin accessibility status. There are distinct regulatory elements that are specifically associated with monocyte or ATM activation in obesity. We also discovered several transcription factors that may regulate monocyte and ATM activation in obese mice, specifically a predicted transcription factor named ETS translocation variant 5 (ETV5). The expression of ETV5 was significantly decreased in ATMs from obese mice and its downregulation was mediated by palmitate stimulation. The decrease in ETV5 expression resulted in macrophage activation. Our results also indicate that ETV5 suppresses endoplasmic reticulum (ER) stress and Il6 expression in macrophages. Our work delineates the changes in chromatin accessibility in monocytes and ATMs during obesity, and identifies ETV5 as a critical transcription factor suppressing ATM activation, suggesting its potential use as a therapeutic target in obesity-related chronic inflammation.

Characterization of Organ-Specific Regulatory B Cells Using Single-Cell RNA Sequencing.

Regulatory B cells (Breg) are considered as immunosuppressive cells. Different subsets of Breg cells have been identified both in human beings and in mice. However, there is a lack of unique markers to identify Breg cells, and the heterogeneity of Breg cells in different organs needs to be further illuminated. In this study, we performed high-throughput single-cell RNA sequencing (scRNA-seq) and single-cell B-cell receptor sequencing (scBCR-seq) of B cells from the murine spleen, liver, mesenteric lymph nodes, bone marrow, and peritoneal cavity to better define the phenotype of these cells. Breg cells were identified based on the expression of immunosuppressive genes and IL-10-producing B (B10) cell-related genes, to define B10 and non-B10 subsets in Breg cells based on the score of the B10 gene signatures. Moreover, we characterized 19 common genes significantly expressed in Breg cells, including Fcrl5, Zbtb20, Ccdc28b, Cd9, and Ptpn22, and further analyzed the transcription factor activity in defined Breg cells. Last, a BCR analysis was used to determine the clonally expanded clusters and the relationship of Breg cells across different organs. We demonstrated that Atf3 may potentially modulate the function of Breg cells as a transcription factor and that seven organ-specific subsets of Breg cells are found. Depending on gene expression and functional modules, non-B10 Breg cells exhibited activated the TGF-ß pathway, thus suggesting that non-B10 Breg cells have specific immunosuppressive properties different from conventional B10 cells. In conclusion, our work provides new insights into Breg cells and illustrates their transcriptional profiles and BCR repertoire in different organs under physiological conditions.

Association of Obstructive Sleep Apnea With the Risk of Repeat Adverse Cardiovascular Events in Patients With Newly Diagnosed Acute Coronary Syndrome: A Systematic Review and Meta-Analysis.

BACKGROUND: The impact of obstructive sleep apnea (OSA) on subsequent cardiovascular events in patients with acute coronary syndrome (ACS) remains inconclusive. AIM: Our aim was to systematically assess the relationship between preexisting OSA and adverse cardiovascular events in patients with newly diagnosed ACS by conducting a systematic review and meta-analysis. METHODS: We systematically searched PubMed, EMBASE, and Cochrane library for studies published up to May 1, 2020, that reported any association between OSA and cardiovascular events in patients with newly diagnosed ACS. The main outcomes were a composite of all-cause or cardiovascular death, recurrent myocardial infarction, stroke, repeat revascularization, or heart failure. We conducted a pooled analysis using the random-effects model. We also performed subgroup, sensitivity, heterogeneity analysis, and the assessment of publication bias. RESULTS: We identified 10 studies encompassing 3350 participants. The presence of OSA was associated with increased risk of adverse cardiovascular events in newly prognosed ACS (risk ratio [RR] 2.18, 95% confidence interval [CI]: 1.45-3.26, P < .001, I2 = 64%). Between-study heterogeneity was partially explained by a multicenter study (9 single-center studies, RR 2.33 95% CI 1.69-3.19, I2 =18%), and I2 remarkably decreased from 64% to 18%. Moreover, OSA significantly increased the incidence of repeat revascularization (8 studies) and heart failure (6 studies) in patients with newly diagnosed ACS. CONCLUSION: Patients with preexisting OSA are at greater risk of subsequent cardiovascular events after onset of ACS. Further studies should investigate the treatment of OSA in patient with ACS.

Replication study and meta-analysis indicate a suggestive association of RUNX3 locus with primary biliary cholangitis.

Susceptibility to primary biliary cholangitis (PBC) is in part genetically determined. In our previous PBC genome-wide association study (GWAS) in 1118 Han Chinese PBC and 4036 controls, we noted that multiple SNPs in the runt-related transcription factor 3 (RUNX3) regions showed a nominally significant association. The tag SNP rs7529070 was genotyped using a TaqMan assay in a separately collected 1435 PBC and 3205 controls. A meta-analysis with a combined 2553 PBC and 7241 controls showed that rs7529070 is still nominally associated with PBC (p = 1.7 × 10-4, odds ratio (OR) = 1.18, 95% confidence interval (CI) = 1.08-1.28). Further analysis indicated that the risk allele of rs7529070 (G allele) is in complete linkage disequilibrium (LD) (r2 = 1) with the G allele of rs4648889, which is known to be associated with increased RUNX3 expression. Bioinformatic analysis with existing expression data showed that the expression of RUNX3 is significantly increased in PBC patients (p = 0.001) and the expression level is correlated with disease severity. Consistently, we also found significantly increased RUNX3 expression (p < 0.01) in the livers of dnTGFßRII mice (a PBC mouse model). This study suggests that the RUNX3 locus may associate with PBC in Han Chinese.

Multi-omics analysis identifies FoxO1 as a regulator of macrophage function through metabolic reprogramming.

Macrophages are plastic cells that can switch among different states according to bioenergetic or biosynthetic requirements. Our previous work demonstrated that the transcription factor Forkhead Box Protein 1 (FoxO1) plays a pivotal role in regulating the function of macrophages, but the underlying mechanisms are still unclear. Here we identify FoxO1 as a regulator of macrophage function through metabolic reprogramming. Transcriptomic and proteomic analyses showed that the deficiency of FoxO1 results in an alternatively activated (M2) phenotype of macrophages, with lower expression of inflammatory response- and migration-associated genes. Using the high content screening and analysis technology, we found that deletion of FoxO1 in macrophages slows their migration rate and impairs their function to limit tumor cell growth in vitro. Next, we demonstrated that glycolysis is inhibited in FoxO1-deficient macrophages, which leads to the observed functional changes and the reduced tumor suppression capability. This prospective study shows that FoxO1 serves as a bridge between metabolism and macrophage function.

Plantar fasciitis in physicians and nurses: a nationwide population-based study.

Physicians and nurses in Taiwan have heavy workload and long working hours, which may contribute to plantar fasciitis. However, this issue is unclear, and therefore, we conducted this study to delineate it. We conducted a nationwide population-based study by identifying 26,024 physicians and 127,455 nurses and an identical number of subjects for comparison (general population) via the National Health Insurance Research Database. The risk of plantar fasciitis between 2006 and 2012 was compared between physicians and general population, between nurses and general population, and between physicians and nurses. We also compared the risk of plantar fasciitis among physician subgroups. Physicians and nurses had a period prevalence of plantar fasciitis of 8.14% and 13.11% during the 7-yr period, respectively. The risk of plantar fasciitis was lower among physicians (odds ratio [OR]: 0.660; 95% confidence interval [CI]: 0.622-0.699) but higher among nurses (OR: 1.035; 95% CI: 1.011-1.059) compared with that in the general population. Nurses also had a higher risk than the physicians after adjusting for age and sex (adjusted odds ratio [AOR]: 1.541; 95% CI: 1.399-1.701). Physician subspecialties of orthopedics and physical medicine and rehabilitation showed a higher risk. Female physicians had a higher risk of plantar fasciitis than male physicians. This study showed that nurses, physician specialties of orthopedics and physical medicine and rehabilitation, and female physicians had a higher risk of plantar fasciitis. Improvement of the occupational environment and health promotion are suggested for these populations.

Tissue-Resident Memory CD8+ T Cells Acting as Mediators of Salivary Gland Damage in a Murine Model of Sjögren's Syndrome.

OBJECTIVE: Although a role for CD4+ T cells in the pathogenesis of Sjögren's syndrome (SS) has been documented, the pathogenic significance of CD8+ T cells is unclear. The aim of this study was to investigate the role of CD8+ T cells in the development of SS. METHODS: Flow cytometry and immunofluorescence analyses were utilized to detect T cell infiltration within the labial salivary glands of patients with primary SS. In parallel, p40-/- CD25-/- mice were used as a murine model of SS. In addition, mice with genetic knockout of CD4, CD8a, or interferon-γ (IFNγ) were crossed with p40-/- CD25-/- mice to study the pathogenic significance of specific lineage subpopulations, including functional salivary gland tests as well as histopathologic and serologic data. A CD8+ T cell-specific depletion antibody was used in this murine SS model to evaluate its potential as a therapeutic strategy. RESULTS: CD8+ T cells with a tissue-resident memory phenotype outnumbered CD4+ T cells in the labial salivary glands of patients with SS, and were primarily colocalized with salivary duct epithelial cells and acinar cells. Furthermore, infiltrating CD8+ T cells with a CD69+CD103+/- tissue-resident phenotype and with a significant elevation of IFNγ production were dominant in the submandibular glands of mice in this murine SS model. CD8a knockout abrogated the development of SS in these mice. Knockout of IFNγ decreased CD8+ T cell infiltration and gland destruction. More importantly, depletion of CD8+ T cells fully protected mice against the pathologic manifestations of SS, even after the onset of disease. CONCLUSION: These data reveal the pathogenic significance of CD8+ T cells in the development and progression of SS in the salivary glands. Treatment directed against CD8+ T cells may be a rational therapy for the management of SS in human subjects.

Polymyositis and dermatomyositis - challenges in diagnosis and management.

Polymyositis (PM) and dermatomyositis (DM) are different disease subtypes of idiopathic inflammatory myopathies (IIMs). The main clinical features of PM and DM include progressive symmetric, predominantly proximal muscle weakness. Laboratory findings include elevated creatine kinase (CK), autoantibodies in serum, and inflammatory infiltrates in muscle biopsy. Dermatomyositis can also involve a characteristic skin rash. Both polymyositis and dermatomyositis can present with extramuscular involvement. The causative factor is agnogenic activation of immune system, leading to immunologic attacks on muscle fibers and endomysial capillaries. The treatment of choice is immunosuppression. PM and DM can be distinguished from other IIMs and myopathies by thorough history, physical examinations and laboratory evaluation and adherence to specific and up-to-date diagnosis criteria and classification standards. Treatment is based on correct diagnosis of these conditions.

CD8+ T cells and IFN-γ induce autoimmune myelofibrosis in mice.

Myelofibrosis usually occurs either as a part of a myelodysplastic syndrome or in conjunction with neoplasia. It is not commonly thought of an autoimmune disease. We reported that p40-/-IL-2Rα-/- (interleukin-12p40 and interleukin-2 receptor alpha double knockout) mice, a mouse model of human primary biliary cholangitis, exhibited features consistent with autoimmune myelofibrosis, including anemia associated with bone marrow fibrosis, and extramedullary hematopoiesis (EMH) including LSK (Lineage-c-Kit+Sca-1+) cells in spleen, liver and peripheral blood. There were also increased LSK cells in bone marrow but they demonstrated impaired hematopoiesis. Importantly effector memory T cells that infiltrated the bone marrow of p40-/-IL-2Rα-/- mice manifested a higher ability to produce IFN-γ. CD8+ T cells, already known to play a dominate role in portal inflammation, were also key for bone marrow dysregulation and EMH. IFN-γ was the key cytokine that induced bone marrow fibrosis, bone marrow failure and EMH. Finally anti-CD8α antibody therapy fully protected p40-/-IL-2Rα-/- mice from autoimmune myelofibrosis. In conclusion, our results demonstrate that CD8+ T cells and IFN-γ are associated with autoimmune myelofibrosis, a finding that may allow targeting of CD8+ T cells and IFN-γ as a therapeutic targets.

The molecular basis of immune regulation in autoimmunity.

Autoimmune diseases can be triggered and modulated by various molecular and cellular characteristics. The mechanisms of autoimmunity and the pathogenesis of autoimmune diseases have been investigated for several decades. It is well accepted that autoimmunity is caused by dysregulated/dysfunctional immune susceptible genes and environmental factors. There are multiple physiological mechanisms that regulate and control self-reactivity, but which can also lead to tolerance breakdown when in defect. The majority of autoreactive T or B cells are eliminated during the development of central tolerance by negative selection. Regulatory cells such as Tregs (regulatory T) and MSCs (mesenchymal stem cells), and molecules such as CTLA-4 (cytotoxic T-lymphocyte associated antigen 4) and IL (interleukin) 10 (IL-10), help to eliminate autoreactive cells that escaped to the periphery in order to prevent development of autoimmunity. Knowledge of the molecular basis of immune regulation is needed to further our understanding of the underlying mechanisms of loss of tolerance in autoimmune diseases and pave the way for the development of more effective, specific, and safer therapeutic interventions.

IFN-γ-STAT1-iNOS Induces Myeloid Progenitors to Acquire Immunosuppressive Activity.

Autoimmune diseases often induce dysregulated hematopoiesis with altered number and function of hematopoietic stem and progenitor cells (HSPCs). However, there are limited studies on the direct regulation of HSPCs on T cells, which are often detrimental to autoimmunity. Here, we found that in a murine model of Concanavalin A-induced autoimmune hepatitis, LSK (Lineage-Sca-1+c-Kit+)-like cells accumulated in liver, spleen, and bone marrow (BM), which were myeloid progenitors (Lineage-Sca-1-c-Kit+) that upregulated Sca-1 expression upon T cell-derived IFN-γ stimulation. Strikingly, BM LSK-like cells from mice induced by Con A to develop autoimmune hepatitis or alternatively myeloid progenitors from wild-type mice possessed strong in vitro suppressive ability. Their suppressive function depended on T cell-derived IFN-γ in a paracrine fashion, which induced STAT1 phosphorylation, inducible nitric oxide synthase expression, and nitric oxide production. Blocking IFN-γ/IFN-γ receptor interaction, knockout of STAT1, or iNOS inhibition abrogated their suppressive function. In addition, the suppressive function was independent of differentiation; mitomycin C-treated myeloid progenitors maintained T cell suppressive ability in vitro. Our data demonstrate a mechanism of inflammation induced suppressive function of myeloid progenitors, which may participate directly in suppressing T cell-mediated immunopathology.

Influence of Metabolic Risk Factors on Risk of Hepatocellular Carcinoma and Liver-Related Death in Men With Chronic Hepatitis B: A Large Cohort Study.

BACKGROUND & AIMS: Little is known about the absolute risk of hepatocellular carcinoma (HCC) and liver-disease related death, in association with metabolic risk factors, for patients with hepatitis B virus (HBV) infection. METHODS: We collected data from 5373 male Taiwanese civil servants who visited Taiwan's Government Employees' Central Clinics and received routine free physical examinations from 1989 through 1992. We obtained information on liver-related morbidity and mortality in HBV carriers, 40-65 years of age (n=1690), with different metabolic risk factors. We compared their medical histories with those of study participants without HBV or HCV infection in the same age range (n=1289). We used patients' baseline data on obesity, diabetes, hypertriglyceridemia, and high blood pressure to assign them to metabolic risk categories. We then performed a case-cohort analysis of the effects of hepatitis B viral factors on risk for HCC, based on metabolic factors and insulin resistance. RESULTS: Over a median follow-up period of 19 years, 158 of the 1690 HBV carriers developed HCC and 126 died from liver-related diseases. Among participants without HBV or HCV infection, only 6 developed HCC or died from liver-related disease. HBV carriers with different metabolic risk factors had significant differences in cumulative incidence of HCC and liver-related death. Patients with 3 or more metabolic risk factors had a substantially higher risk for HCC (10-year cumulative incidence, 13.60%) than patients with a low metabolic risk profile (10-year cumulative incidence, 4.83%; adjusted-hazard ratio, 2.32; 95% CI, 1.18-4.54). Smoking had a significant effect on this association (Pinteraction = .0044). Having 3 or more metabolic risk factors, compared with no factors, significantly increased the risk of HCC (adjusted-hazard ratio, 5.06; 95% CI, 2.23-11.47) and 10-year cumulative incidence of HCC (25.0% in smokers with 3 or more metabolic risk factors vs 3.87% in smokers with none; P < .0001) in smokers, but did not increase risk of HCC in nonsmokers. Metabolic risk factors and insulin resistance had the largest effect on HCC risk in patients with levels of HBV-DNA <10,000 copies/mL. CONCLUSIONS: In a study of men with chronic HBV infection ages 40-65 years in Taiwan, we associated a high burden of metabolic risk factors with increased risk of HCC; smoking has a significant effect on this association.