Overexpression of LAG-3: a potential indicator of low immune function in tuberculosis.

Background: Tuberculosis (TB) persists as a global health challenge, with its treatment hampered by the side effects of long-term combination drug therapies and the growing issue of drug resistance. Therefore, the development of novel therapeutic strategies is critical. This study focuses on the role of immune checkpoint molecules (ICs) and functions of CD8+ T cells in the search for new potential targets against TB. Methods: We conducted differential expression genes analysis and CD8+ T cell functional gene analysis on 92 TB samples and 61 healthy individual (HI) samples from TB database GSE83456, which contains data on 34,603 genes. The GSE54992 dataset was used to validated the findings. Additionally, a cluster analysis on single-cell data from primates infected with mycobacterium tuberculosis and those vaccinated with BCG was performed. Results: The overexpression of LAG-3 gene was found as a potentially important characteristic of both pulmonary TB (PTB) and extrapulmonary TB (EPTB). Further correlation analysis showed that LAG-3 gene was correlated with GZMB, perforin, IL-2 and IL-12. A significant temporal and spatial variation in LAG-3 expression was observed in T cells and macrophages during TB infection and after BCG vaccination. Conclusion: LAG-3 was overexpressed in TB samples. Targeting LAG-3 may represent a potential therapeutic target for tuberculosis.

The function role of HIGD1A in nonalcoholic steatohepatitis from chronic hepatitis B.

BACKGROUND: Accompanied by the growing prevalence of nonalcoholic fatty liver disease (NAFLD), the coexistence of chronic hepatitis B (CHB) and NAFLD has increased. In the context of CHB, there is limited understanding of the factors that influence the development of NASH. METHODS: We enrolled CHB combined NAFLD patients who had liver biopsy and divided them to NASH vs. non-NASH groups. A whole transcriptome chip was used to examine the expression profiles of long noncoding RNAs (lncRNAs) and mRNA in biopsied liver tissues. The function analysis of HIGD1A were performed. We knocked down or overexpressed HIGD1A in HepG2.2.15 cells by transient transfection of siRNA-HIGD1A or pcDNA-HIGD1A. In vivo investigations were conducted using hepatitis B virus (HBV) transgenic mice. RESULTS: In 65 patients with CHB and NAFLD, 28 were patients with NASH, and 37 were those without NASH. After screening 582 differentially expressed mRNAs, GO analysis revealed differentially expressed mRNAs acting on nicotinamide adenine dinucleotide phosphate (NADPH), which influenced redox enzyme activity. KEGG analysis also shown that they were involved in the NAFLD signaling pathway. The function analysis revealed that HIGD1A was associated with the mitochondrion. Then, both in vivo and in vitro CHB model, HIGD1A was significantly higher in the NASH group than in the non-NASH group. HIGD1A knockdown impaired mitochondrial transmembrane potential and induced cell apoptosis in HepG2.2.15 cells added oleic acid and palmitate. On the contrary, hepatic HIGD1A overexpression ameliorated free fatty acids-induced apoptosis and oxidative stress. Furthermore, HIGD1A reduced reactive oxygen species (ROS) level by increasing glutathione (GSH) expression, but Adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK)/Acetyl-CoA carboxylase (ACC) pathway was not involved. CONCLUSION: Both in vivo and in vitro CHB model, an upward trend of HIGD1A was observed in the NASH-related inflammatory response. HIGDIA played a protective role in cells against oxidative stress. Our data suggested that HIGD1A may be a positive regulator of NASH within the CHB context.

Immune checkpoint inhibitors in cancer patients with COVID-19.

Immune checkpoint inhibitors (ICIs) are widely used to treat a variety of cancers and common infectious diseases with high efficacy. During the coronavirus disease 2019 (COVID-19) pandemic, studies suggested that COVID-19 patients may benefit from ICI immunotherapy. However, clinical studies on the safety and efficacy of ICI in COVID-19 patients are still being conducted. Currently, it is not clear whether cancer patients undergoing ICI immunotherapy should adjust their treatment strategy after infection with SARS-CoV-2 and whether ICI can reduce the viral load of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In this study, reports of patients with different types of tumors infected with SARS-CoV-2 under ICI immunotherapy were classified and sorted, including lung cancer, melanoma, squamous cell carcinoma of the head and neck, and hematologic malignances. The safety and efficacy of ICI in antitumor and anti-SARS-CoV-2 therapies were compared and further discussed to provide more reference materials for the application of ICI treatment. In a word, COVID-19 has changed the ICI treatment strategy for cancer patients indeed, and ICI treatment may be a "double-edged sword" for cancer patients complicated with COVID-19.

Body composition and risk of liver cancer: a population-based prospective cohort study on gender difference.

Background: Obesity is a common and highly convincing risk factor for many cancers, including liver cancer. Sex disparities in the body composition and regulatory mechanisms involved in energy homeostasis may contribute to the difference in the incidence of cancer. However, evidence on the gender-specific association between body composition and liver cancer incidence is limited. We performed this study to investigate the linear and non-linear associations of body composition with liver cancer risk by gender. Materials and methods: This prospective analysis included 4,75,659 participants free of cancer, based on the UK Biobank. We used Cox proportional hazard models to calculate the hazard ratios (HRs) and 95% confidence intervals (CIs) after adjusting for potential confounders. Restricted cubic spline was performed to investigate the potential non-linear associations. Results: During a median follow-up, 275 cases (174 male patients and 101 female patients) of liver cancer were identified. Male patients in the highest body fat percentage group are more likely to develop liver cancer (HR = 1.89, 95% CI: 1.17-3.03) compared with those in the lowest group. The one-unit increase of whole-body fat mass, arm fat mass, and trunk fat mass was associated with 1.03-, 1.14-, and 1.05-fold increased risk of liver cancer in male subjects, respectively. U-shaped associations of body composition with liver cancer risk were observed in the female subjects. Both high and low levels of whole-body fat-free mass, particularly in the arm and trunk, were associated with an increased risk of liver cancer. Conclusion: This study found a gender-specific association between body composition and liver cancer risk and provided evidence for individualized weight management for the prevention of liver cancer.

Clinical Features of Non-Alcoholic Fatty Liver Disease in the Non-Lean Population.

INTRODUCTION: The prevalence of non-alcoholic fatty liver disease (NAFLD) in non-lean patients is significantly increased, and obesity significantly increases the risk of cirrhosis and HCC in NAFLD patients. However, whether there is a difference in clinical manifestations of NAFLD between overweight and obesity remains unclear. The objective of this study was to assess the clinical and histological features of NAFLD among a non-lean population. METHODS: Current study enrolled consecutive non-lean (body mass index [BMI] >23 kg/m2) patients with NAFLD and available liver biopsy results. Patients were stratified by BMI into two groups for the comparison of their clinical and histological variables, which included the overweight (BMI 23∼<28 kg/m2) and the obese (BMI ≥28 kg/m2). Risk factors for moderate to severe fibrosis (stage >1) were also analyzed through the logistic regression model. RESULTS: Among 184 non-lean patients with metabolic-associated fatty liver disease enrolled, 65 and 119 were overweight and obese, respectively. Patients in the obesity group had a significantly lower level of gamma-glutamyl transpeptidase, higher levels of platelet, glucose, prothrombin time, and more common of moderate to severe inflammatory activity when compared to those in the overweight group. However, a significant low frequency of moderate to severe fibrosis was found in the obesity group versus the overweight group (19.33% vs. 40.00%, p = 0.002). Binary logistics regression analysis of fibrosis found that aspartate transaminase (AST), BMI, alanine transaminase (ALT), and cholesterol (CHOL) were independent predictors for moderate to severe fibrosis in non-lean patients with NAFLD. Compared with the traditional fibrosis-4 (AUC = 0.77) and aminotransferase to platelet ratio index (AUC = 0.79) indexes, the combined index based on AST, BMI, ALT, and CHOL was more accurate in predicting moderate to severe fibrosis in non-lean patients with NAFLD (AUC = 0.87). CONCLUSIONS: Clinical and histological features differed between obesity and overweight patients with NAFLD. When compared to the traditional serum markers, the combination index including AST, BMI, ALT, and CHOL provided a better model to predict moderate to severe fibrosis in non-lean patients with NAFLD.

SARS-CoV-2 N protein enhances the anti-apoptotic activity of MCL-1 to promote viral replication.

Viral infection in respiratory tract usually leads to cell death, impairing respiratory function to cause severe disease. However, the diversity of clinical manifestations of SARS-CoV-2 infection increases the complexity and difficulty of viral infection prevention, and especially the high-frequency asymptomatic infection increases the risk of virus transmission. Studying how SARS-CoV-2 affects apoptotic pathway may help to understand the pathological process of its infection. Here, we uncovered SARS-CoV-2 imployed a distinct anti-apoptotic mechanism via its N protein. We found SARS-CoV-2 virus-like particles (trVLP) suppressed cell apoptosis, but the trVLP lacking N protein didn't. Further study verified that N protein repressed cell apoptosis in cultured cells, human lung organoids and mice. Mechanistically, N protein specifically interacted with anti-apoptotic protein MCL-1, and recruited a deubiquitinating enzyme USP15 to remove the K63-linked ubiquitination of MCL-1, which stabilized this protein and promoted it to hijack Bak in mitochondria. Importantly, N protein promoted the replications of IAV, DENV and ZIKV, and exacerbated death of IAV-infected mice, all of which could be blocked by a MCL-1 specific inhibitor, S63845. Altogether, we identifed a distinct anti-apoptotic function of the N protein, through which it promoted viral replication. These may explain how SARS-CoV-2 effectively replicates in asymptomatic individuals without cuasing respiratory dysfunction, and indicate a risk of enhanced coinfection with other viruses. We anticipate that abrogating the N/MCL-1-dominated apoptosis repression is conducive to the treatments of SARS-CoV-2 infection as well as coinfections with other viruses.

Mesenchymal stem cells attenuate sepsis-induced liver injury via inhibiting M1 polarization of Kupffer cells.

Sepsis is a leading cause of death in intensive care units that can result in acute hepatic damage. Animal experiments and clinical trials have shown that mesenchymal stem cell (MSC) therapy has some beneficial in several liver diseases. However, the protective effects of MSC therapy on sepsis-induced hepatic damage and associated mechanisms are not completely understood. The aim of the present study was to investigate the effects of MSCs on sepsis-induced liver injury and underlying mechanisms. A rat model of sepsis-induced liver injury was established by cecal ligation and puncture, and serum alanine aminotransferase and aspartate transaminase activities as well as liver histological changes were measured. Inflammatory cytokines, Kupffer cell M1 phenotype markers, and associated signal molecules were also determined in septic rats and in lipopolysaccharide (LPS)-treated Kupffer cells. Our results showed that injection of MSCs attenuated sepsis-induced liver injury. Treatment with MSCs inhibited activation of Kupffer cells towards M1 phenotype, attenuated TNF-α and IL-6 expression, and promoted IL-4 and IL-10 expression in septic rats and LPS-treated Kupffer cells. Furthermore, MSCs also inhibited the nuclear translocation of nuclear factor-kappa B in LPS-challenged Kupffer cells and the liver of septic rats. These results indicated that MSCs attenuated sepsis-induced liver injury through suppressing M1 polarization of Kupffer cells.

HGF and direct mesenchymal stem cells contact synergize to inhibit hepatic stellate cells activation through TLR4/NF-kB pathway.

AIMS: Bone marrow-derived mesenchymal stem cells (BMSCs) can reduce liver fibrosis. Apart from the paracrine mechanism by which the antifibrotic effects of BMSCs inhibit activated hepatic stellate cells (HSCs), the effects of direct interplay and juxtacrine signaling between the two cell types are poorly understood. The purpose of this study was to explore the underlying mechanisms by which BMSCs modulate the function of activated HSCs. METHODS: We used BMSCs directly and indirectly co-culture system with HSCs to evaluate the anti-fibrosis effect of BMSCs. Cell proliferation and activation were examined in the presence of BMSCs and HGF. c-met was knockdown in HSCs to evaluate the effect of HGF secreted by BMSCs. The TLR4 and Myeloid differentiation primary response gene 88(MyD88) mRNA levels and the NF-kB pathway activation were determined by real-time PCR and western blotting analyses. The effect of BMSCs on HSCs activation was investigated in vitro in either MyD88 silencing or overexpression in HSCs. Liver fibrosis in rats fed CCl(4) with and without BMSCs supplementation was compared. Histopathological examinations and serum biochemical tests were compared between the two groups. RESULTS: BMSCs remarkably inhibited the proliferation and activation of HSCs by interfering with LPS-TLR4 pathway through a cell-cell contact mode that was partially mediated by HGF secretion. The NF-kB pathway is involved in HSCs activation inhibition by BMSCs. MyD88 over expression reduced the BMSC inhibition of NF-kB luciferase activation. BMSCs protected liver fibrosis in vivo. CONCLUSION: BMSCs modulate HSCs in vitro via TLR4/MyD88/NF-kB signaling pathway through cell-cell contact and secreting HGF. BMSCs have therapeutic effects on cirrhosis rats. Our results provide new insights into the treatment of hepatic fibrosis with BMSCs.

Differentiation of human umbilical cord mesenchymal stem cells into hepatocyte-like cells by hTERT gene transfection in vitro.

The availability of a large quantity of MSCs (mesenchymal stem cells) would greatly advance liver-directed cell therapies. However, MSCs have a limited lifespan in vitro. Therefore we tested whether hUCMSCs (human umbilical cord MSCs) could be immortalized by transduction with a lentiviral vector carrying the hTERT (human telomerase reverse transcriptase) catalytic subunit gene, and investigated their differentiation potential. Transfected hUCMSCs overexpressed the hTERT gene and up-regulated their telomerase activity. The transfected hUCMSCs maintained their typical morphology and MSC-specific markers, and vigorously proliferated, undergoing more than 100 PDs (population doublings) to date. Following incubation with hepatogenic agents, the transfected hUCMSCs differentiated into hepatocyte-like cells, and expressed hepatic markers, such as albumin, AFP (α-fetoprotein) and CK-18 (cytokeratin-18). Transfected hUCMSCs showed no transformation into tumours in nude mice. In conclusion, telomerization of hUCMSCs by hTERT overexpression extends their replicative lifespan without influencing their hepatogenic differentiation potential. This offers opportunities for obtaining sufficient quantities of cells for liver-directed therapies.

[Impact of body mass index on blood pressures in a college student population].

OBJECTIVE: To explore the morbidity of hypertension and prehypertension and analyze the association between body mass index (BMI) and blood pressure in Chinese college students. METHODS: This epidemiological study involved 490 Chinese college students (aged 15-25 years, mean 18.9∓1.2 years), and their body height, body weight, blood pressure and heart rate were recorded. The BMI was divided into four groups according to Chinese population standard classification. RESULTS: Most students were southern Han Chinese. The incidences of overweight plus obesity and obesity were 12.9% and 4.1%, respectively. The morbidity of hypertension was 0.8% in this student population. The incidences of hypertension and pre-hypertension were higher in high BMI groups than those in low BMI groups. The systolic blood pressures were significantly higher in over-weight and obese groups than in the normal BMI and lean groups. BMI was positively correlated to systolic and diastolic blood pressures in this population. CONCLUSION: High BMI is a predictor of elevated blood pressure in adolescent students.

Construction of non-covalent single-chain Fv dimers for hepatocellular carcinoma and their biological functions.

AIM: To create new diabodies with improved binding activity to antigen of the variable light - variable heavy (VH-VL) oriented single-chain Fv dimers genes (scFv). METHODS: The linker between VH and VL genes was shortened to 3-5 amino acid residues and cloned into the vector pCANTAB5E. The recombinant plasmids were transformed into TG1 cells and sequenced. The positive transformed cells were infected by M13K07 helper phage to form human recombinant phage antibodies. Expressed products were identified by SDS-PAGE, Western blotting, size exclusion gel chromatography (SEC), ELISA and immunohistochemistry. RESULTS: Three scFv (scFv-3, scFv-4, scFv-5) were constructed successfully with binding ability to hepatocellular carcinoma 3.5-6 fold greater than their parental scFv. The single-chain Fv dimer (scFv-5, termed BDM3) with the best binding ability was successfully expressed in Yeast pichlia, as shown by. SDS-PAGE and Western blotting. SEC results suggested the molecular weight of the expressed products was about 61 kDa. Expressed products showed significantly stronger binding to hepatocellular carcinoma cells than scFv, still having 50% binding activity even after 16 h incubation as 37°C. The purified dimers were bound specifically to the tumor antigen of HCC. CONCLUSION: we have generated scFv dimers by shortening a series of linkers to 3-5 amino acid residues in VH-linker-VL orientation, resulting in highly stable and affinity-improved dimeric molecules. These will become an attractive targeting moiety in immunotherapeutic and diagnostic applications for HCC.