COVID-19 immune features revealed by a large-scale single-cell transcriptome atlas.

A dysfunctional immune response in coronavirus disease 2019 (COVID-19) patients is a recurrent theme impacting symptoms and mortality, yet a detailed understanding of pertinent immune cells is not complete. We applied single-cell RNA sequencing to 284 samples from 196 COVID-19 patients and controls and created a comprehensive immune landscape with 1.46 million cells. The large dataset enabled us to identify that different peripheral immune subtype changes are associated with distinct clinical features, including age, sex, severity, and disease stages of COVID-19. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA was found in diverse epithelial and immune cell types, accompanied by dramatic transcriptomic changes within virus-positive cells. Systemic upregulation of S100A8/A9, mainly by megakaryocytes and monocytes in the peripheral blood, may contribute to the cytokine storms frequently observed in severe patients. Our data provide a rich resource for understanding the pathogenesis of and developing effective therapeutic strategies for COVID-19.

An inhibitor of leukotriene-A4 hydrolase from bat salivary glands facilitates virus infection.

SignificanceAn immunosuppressant protein (MTX), which facilitates virus infection by inhibiting leukotriene A4 hydrolase (LTA4H) to produce the lipid chemoattractant leukotriene B4 (LTB4), was identified and characterized from the submandibular salivary glands of the bat Myotis pilosus. To the best of our knowledge, this is a report of an endogenous LTA4H inhibitor in animals. MTX was highly concentrated in the bat salivary glands, suggesting a mechanism for the generation of immunological privilege and immune tolerance and providing evidence of viral shedding through oral secretions. Moreover, given that the immunosuppressant MTX selectively inhibited the proinflammatory activity of LTA4H, without affecting its antiinflammatory activity, MTX might be a potential candidate for the development of antiinflammatory drugs by targeting the LTA4-LTA4H-LTB4 inflammatory axis.

Metabolic biomarkers significantly enhance the prediction of HBV-related ACLF occurrence and outcomes.

BACKGROUND & AIMS: Acute-on-chronic liver failure (ACLF) is a clinical syndrome associated with high short-term mortality in patients with chronic liver disease. Chronic hepatitis B is the main cause of ACLF (HBV-ACLF) in China and other Asian countries. To improve disease management and survival for patients with ACLF, we aimed to discover novel biomarkers to enhance HBV-ACLF diagnosis and prognostication. METHODS: We performed a metabolomics profiling of 1,024 plasma samples collected from patients with HBV-related chronic liver disease with acute exacerbation at hospital admission in a multi-year and multi-center prospective study (367 ACLF and 657 non-ACLF). The samples were randomly separated into equal halves as a discovery set and a validation set. We identified metabolites associated with 90-day mortality in the ACLF group and the progression to ACLF within 28 days in the non-ACLF group (pre-ACLF) using statistical analysis and machine learning. We developed diagnostic algorithms in the discovery set and used these to assess the findings in the validation set. RESULTS: ACLF significantly altered the plasma metabolome, particularly in membrane lipid metabolism, steroid hormones, oxidative stress pathways, and energy metabolism. Numerous metabolites were significantly associated with 90-day mortality in the ACLF group and/or pre-ACLF in the non-ACLF group. We developed algorithms for the prediction of 90-day mortality in patients with ACLF (area under the curve 0.87 and 0.83 for the discovery set and validation set, respectively) and the diagnosis of pre-ACLF (area under the curve 0.94 and 0.88 for the discovery set and validation set, respectively). To translate our discoveries into practical clinical tests, we developed targeted assays using liquid chromatography-mass spectrometry. CONCLUSIONS: Based on novel metabolite biomarkers, we established tests for HBV-related ACLF with higher accuracy than existing methods. CLINICAL TRIAL NUMBER: NCT02457637 and NCT03641872. IMPACT AND IMPLICATIONS: Acute-on-chronic liver failure (ACLF) is a clinical syndrome associated with high short-term mortality affecting 25% of patients hospitalized with cirrhosis. Chronic hepatitis B is the main etiology of ACLF in China and other Asian counties. There is currently no effective therapy. Early diagnosis and accurate prognostication are critical for improving clinical outcomes in patients with ACLF. Based on novel metabolite biomarkers, we developed liquid chromatography-mass spectrometry tests with improved accuracy for the early diagnosis and prognostication of HBV-related ACLF. The liquid chromatography-mass spectrometry tests can be implemented in clinical labs and used by physicians to triage patients with HBV-related ACLF to ensure optimized clinical management.

Portal vein thrombosis compromises the performance of MELD and MELD-Na scores in patients with cirrhosis.

BACKGROUND AND AIMS: The accuracy of model for end-stage liver disease (MELD) and MELD with sodium (MELD-Na) scores in reflecting the clinical outcomes of patients with cirrhosis and portal vein thrombosis (PVT) remains unclear. This study aimed to evaluate the performance of scores in predicting 90-day mortality in patients with cirrhosis and PVT. METHODS: Post hoc analysis was performed in two prospective cohorts (NCT02457637 and NCT03641872). The correlation between the MELD/MELD-Na score and 90-day liver transplantation (LT)-free mortality was investigated in patients with cirrhosis with and without PVT. RESULTS: In this study, 2826 patients with cirrhosis were included, and 255 (9.02%) had PVT. The cumulative incidence of 90-day LT-free mortality did not significantly differ between patients with and without PVT (log-rank P = 0.0854). MELD [area under the receiver operating curve (AUROC), 0.649 vs. 0.842; P = 0.0036] and MELD-Na scores (AUROC, 0.691 vs. 0.851; P = 0.0108) were compared in patients with and without PVT, regarding the prediction of 90-day LT-free mortality. In MELD < 15 and MELD-Na < 20 subgroups, patients with PVT had a higher 90-day LT-free mortality than those without PVT (7.91% vs. 2.64%, log-rank P = 0.0011; 7.14% vs. 3.43%, log-rank P = 0.0223), whereas in MELD ≥ 15 and MELD-Na ≥ 20 subgroups, no significant difference was observed between patients with and without PVT. CONCLUSIONS: The performance of MELD and MELD-Na scores in predicting 90-day LT-free mortality of patients with cirrhosis was compromised by PVT. MELD < 15 or MELD-Na < 20 may underestimate the 90-day LT-free mortality in patients with PVT.

A novel prognostic nomogram for older patients with acute-on-chronic liver diseases (AoCLD): a nationwide, multicentre, prospective cohort study.

BACKGROUND: the incidence of acute-on-chronic liver disease (AoCLD) is increasing. OBJECTIVE: to investigate the clinical features and risk factors of AoCLD and construct an effective prognostic nomogram model for older patients with AoCLD. METHODS: data from 3,970 patients included in the CATCH-LIFE study were used, including 2,600 and 1,370 patients in the training and validation sets, respectively. Multivariate Cox regression analyses were performed to identify predictive risk factors in older individuals, and an easy-to-use nomogram was established. Performance was assessed using area under the curve, calibration plots and decision curve analysis (DCA). RESULTS: of the 3,949 patients with AoCLD, 809 were older with a higher proportion of autoimmune-related abnormalities, hepatitis C viral infection and schistosomiasis. In the older patient group, the incidence of cirrhosis, hepatic encephalopathy (HE), infection, ascites and gastrointestinal bleeding; neutrophil-to-lymphocyte ratio (NLR), aspartate-to-alanine transaminase ratio (AST/ALT), creatinine and blood urea nitrogen levels were higher, whereas incidence of acute-on-chronic liver failure, white blood cell, platelet and haemoglobin levels; albumin, total bilirubin (TB), AST and ALT levels; international normalised ratio (INR), estimated glomerular filtration rate and blood potassium levels were lower than in the younger group. The final nomogram was developed based on the multivariate Cox analysis in training cohort using six risk factors: ascites, HE grades, NLR, TB, INR and AST/ALT. Liver transplantation-free mortality predictions were comparable between the training and validation sets. DCA showed higher net benefit for the nomograph than the treat-all or treat-none strategies, with wider threshold probabilities ranges. CONCLUSIONS: our analysis will assist clinical predictions and prognoses in older patients with AoCLD.

Role of LL-37 in thrombotic complications in patients with COVID-19.

Blood clot formation induced by dysfunctional coagulation is a frequent complication of coronavirus disease 2019 (COVID-19) and a high-risk factor for severe illness and death. Neutrophil extracellular traps (NETs) are implicated in COVID-19-induced immunothrombosis. Furthermore, human cathelicidin, a NET component, can perturb the interaction between the SARS-CoV-2 spike protein and its ACE2 receptor, which mediates viral entry into cells. At present, however, the levels of cathelicidin antimicrobial peptides after SARS-CoV-2 infection and their role in COVID-19 thrombosis formation remain unclear. In the current study, we analyzed coagulation function and found a decrease in thrombin time but an increase in fibrinogen level, prothrombin time, and activated partial thromboplastin time in COVID-19 patients. In addition, the cathelicidin antimicrobial peptide LL-37 was upregulated by the spike protein and significantly elevated in the plasma of patients. Furthermore, LL-37 levels were negatively correlated with thrombin time but positively correlated with fibrinogen level. In addition to platelet activation, cathelicidin peptides enhanced the activity of coagulation factors, such as factor Xa (FXa) and thrombin, which may induce hypercoagulation in diseases with high cathelicidin peptide levels. Injection of cathelicidin peptides promoted the formation of thrombosis, whereas deletion of cathelicidin inhibited thrombosis in vivo. These results suggest that cathelicidin antimicrobial peptide LL-37 is elevated during SARS-CoV-2 infection, which may induce hypercoagulation in COVID-19 patients by activating coagulation factors.

Severe anemia is associated with increased short-term and long-term mortality in patients hospitalized with cirrhosis.

INTRODUCTION AND OBJECTIVES: The relationship between anemia and the outcome of patients with cirrhosis is not completely clear. Therefore, we performed this large-scale epidemiological study to investigate the prevalence and severity of anemia in patients with cirrhosis and acute decompensation or liver injury and how anemia impacts short-term and long-term outcomes. PATIENTS AND METHODS: Patients with cirrhosis and acute decompensation (AD) or acute liver injury (ALI) were enrolled in the Chinese AcuTe on CHronic LIver FailurE (CATCH-LIFE) studies, which consisted of two large, multicenter, prospective, observational cohorts between January 2015 and December 2016 and July 2018 and January 2019. We conducted data analysis on the prevalence of anemia and determined the relationship between anemia and prognosis. RESULTS: Among 1979 patients, 1389 (70.2%) had anemia, among whom 599 (41.3%) had mild anemia, 595 (15.8%) had moderate anemia and 195 (2.4%) had severe anemia. A linear association between hemoglobin level and 90-day or 1-year LT-free mortality was shown, and a 10 g/L decrease in hemoglobin level was associated with a 6.8% extra risk of 90-day death and a 5.7% extra risk of 1-year death. Severe anemia was an independent risk factor for 90-day [HR=1.649 (1.100, 2.473), p=0.016] and 1-year LT-free mortality [HR=1.610 (1.159, 2.238), p=0.005]. Multinomial logistic regression analysis further identified that severe anemia was significantly associated with post-28-day mortality but not within-28-day mortality. CONCLUSIONS: Anemia is common in patients with cirrhosis admitted for acute events. Severe anemia was associated with poor 90-day and 1-year prognoses in these patients.

Longitudinal and Lateral Control Strategies for Automatic Lane Change to Avoid Collision in Vehicle High-Speed Driving.

The vehicle particle model was built to compare and analyze the effectiveness of three different collision avoidance methods. The results show that during vehicle high-speed emergency collision avoidance, lane change collision avoidance requires a smaller longitudinal distance than braking collision avoidance and is closer to that with a combination of lane change and braking collision avoidance. Based on the above, a double-layer control strategy is proposed to avoid collision when vehicles change lanes at high speed. The quintic polynomial is chosen as the reference path after comparing and analyzing three polynomial reference trajectories. The multiobjective optimized model predictive control is used to track the lateral displacement, and the optimization objective is to minimize the lateral position deviation, yaw rate tracking deviation, and control increment. The lower longitudinal speed tracking control strategy is to control the vehicle drive system and brake system to track the expected speed. Finally, the lane changing conditions and other speed conditions of the vehicle at 120 km/h are verified. The results show that the control strategy can track the longitudinal and lateral trajectories well and achieve effective lane change and collision avoidance.

MELD score < 18 rule out 28-day ACLF development among inpatients with hepatitis B-related previous compensated liver disease.

The acute-on-chronic liver failure (ACLF) development is highly dynamic. Currently, no satisfactory algorithm identifies patients with HBV at risk of this complication. The aim of the study was to characterize ACLF development in hospitalized HBV-related patients without previous decompensation and to test the performance of traditional prognostic models in ruling out ACLF development within 28 days on admission we conducted a cohort study. Two multi-center cohorts with hospitalized HBV-related previous compensated patients were analyzed. Performances of MELD, MELD-Na, CLIF-C AD, and CLIF-C ACLF-D in ruling out ACLF development within 28 days were compared and further validated by ROC analyses. In the derivation cohort (n = 892), there were 102 patients developed ACLF within 28 days, with profound systemic inflammatory levels and higher 28-day mortality rate (31.4% vs. 1.0%) than those without ACLF development. The MELD score (cut-off = 18) achieved acceptable missing rate (missed/total ACLF development) at 2.9%. In the validation cohort (n = 1656), the MELD score (<18) was able to rule out ACLF development within 28 days with missing rate at 3.0%. ACLF development within 28 days were both lower than 1% (0.6%, derivation cohort; 0.5%, validation cohort) in patients with MELD < 18. While in patients with MELD ≥ 18, 26.6% (99/372, derivation cohort) and 17.8% (130/732, validation cohort) developed into ACLF within 28 days, respectively. While MELD-Na score cut-off at 20 and CLIF-AD score cut-off at 42 did not have consistent performance in our two cohorts. MELD < 18 was able to safely rule out patients with ACLF development within 28 days in HBV-related patients without previous decompensation, which had a high 28-day mortality.

Causal effect of autoimmune liver diseases on cancer: Meta-analyses of cohort studies and Mendelian randomization study.

BACKGROUND AND AIMS: Prior studies suggested that patients with autoimmune liver diseases (AiLDs) had an increased risk of cancer, whereas the causal effect remained unclear. METHODS: Meta-analyses concerning the relationship between AiLD and cancer risk were performed to calculate the pooled relative risk (RR) and corresponding 95% confidence intervals (CIs). Then, the associations with a p value of <.05 were further validated by two-sample Mendelian randomization studies. RESULTS: A total of 37 cohort studies covering more than 34 558 patients were included, and we observed an increased risk of overall cancers (pooled RR = 3.64, 95% CI: 2.64-5.03, p < .001) and cancer-related death (pooled RR = 2.48, 95% CI: 1.73-3.53, p < .001) for patients with AiLD. Besides, overall and several site-specific cancers risk were found in patients with primary biliary cholangitis (PBC), autoimmune hepatitis (AIH), and primary sclerosing cholangitis (PSC) (p < .05). However, associations between genetically predisposed AIH, PBC, and PSC and the risk of specific cancers did not reach a significant level, except for PBC and gastric cancer (OR = 0.96, 95% CI: 0.93-0.99; p = .02). CONCLUSIONS: In addition to hepatobiliary cancer, results from the meta-analyses suggest that patients with AiLD might have an increased risk of several extrahepatobiliary cancers. However, the causal role of AiLD in cancer development needs to be further investigated.

Genetic studies of body mass index yield new insights for obesity biology.

Obesity is heritable and predisposes to many diseases. To understand the genetic basis of obesity better, here we conduct a genome-wide association study and Metabochip meta-analysis of body mass index (BMI), a measure commonly used to define obesity and assess adiposity, in up to 339,224 individuals. This analysis identifies 97 BMI-associated loci (P < 5 × 10(-8)), 56 of which are novel. Five loci demonstrate clear evidence of several independent association signals, and many loci have significant effects on other metabolic phenotypes. The 97 loci account for ∼2.7% of BMI variation, and genome-wide estimates suggest that common variation accounts for >20% of BMI variation. Pathway analyses provide strong support for a role of the central nervous system in obesity susceptibility and implicate new genes and pathways, including those related to synaptic function, glutamate signalling, insulin secretion/action, energy metabolism, lipid biology and adipogenesis.

TNF-α/IFN-γ profile of HBV-specific CD4 T cells is associated with liver damage and viral clearance in chronic HBV infection.

BACKGROUND & AIMS: The role of hepatitis B virus (HBV)-specific CD4 T cells in patients with chronic HBV infection is not clear. Thus, we aimed to elucidate this in patients with chronic infection, and those with hepatitis B flares. METHODS: Through intracellular IFN-γ and TNF-α staining, HBV-specific CD4 T cells were analyzed in 68 patients with chronic HBV infection and alanine aminotransferase (ALT) <2x the upper limit of normal (ULN), and 28 patients with a hepatitis B flare. HBV-specific HLA-DRB1*0803/HLA-DRB1*1202-restricted CD4 T cell epitopes were identified. RESULTS: TNF-α producing cells were the dominant population in patients' HBV-specific CD4 T cells. In patients with ALT <2xULN, both the frequency and the dominance of HBV-specific IFN-γ producing CD4 T cells increased sequentially in patients with elevated levels of viral clearance: HBV e antigen (HBeAg) positive, HBeAg negative, and HBV surface antigen (HBsAg) negative. In patients with a hepatitis B flare, the frequency of HBV core-specific TNF-α producing CD4 T cells was positively correlated with patients' ALT and total bilirubin levels, and the frequency of those cells changed in parallel with the severity of liver damage. Patients with HBeAg/HBsAg loss after flare showed higher frequency and dominance of HBV-specific IFN-γ producing CD4 T cells, compared to patients without HBeAg/HBsAg loss. Both the frequency and the dominance of HBV S-specific IFN-γ producing CD4 T cells were positively correlated with the decrease of HBsAg during flare. A differentiation process from TNF-α producing cells to IFN-γ producing cells in HBV-specific CD4 T cells was observed during flare. Eight and 9 HBV-derived peptides/pairs were identified as HLA-DRB1*0803 restricted epitopes and HLA-DRB1*1202 restricted epitopes, respectively. CONCLUSIONS: HBV-specific TNF-α producing CD4 T cells are associated with liver damage, while HBV-specific IFN-γ producing CD4 T cells are associated with viral clearance in patients with chronic HBV infection. LAY SUMMARY: TNF-α producing cells are the dominant population of hepatitis B virus (HBV)-specific CD4 T cells in patients with chronic HBV infection. This population of cells might contribute to the aggravation of liver damage in patients with a hepatitis B flare. HBV-specific IFN-γ producing CD4 T cells are associated with HBV viral clearance. Differentiation from HBV-specific TNF-α producing CD4 T cells into HBV-specific IFN-γ producing CD4 T cells might favor HBV viral clearance.

Prevalence and Clinical Significance of Portal Vein Thrombosis in Patients With Cirrhosis and Acute Decompensation.

BACKGROUND & AIMS: Portal vein thrombosis (PVT) is a common and serious complication in patients with cirrhosis. However, little is known about PVT in patients with cirrhosis and acute decompensation (AD). We investigated the prevalence and clinical significance of PVT in nonmalignant patients with cirrhosis and AD. METHODS: We performed a retrospective study of 2 cohorts of patients with acute exacerbation of chronic liver disease who participated in the Chinese AcuTe on CHronic LIver FailurE study, established by the Chinese Chronic Liver Failure Consortium, from January 2015 through December 2016 (n = 2600 patients) and July 2018 through January 2019 (n = 1370 patients). We analyzed data on the prevalence, clinical manifestations, and risk factors of PVT from 2826 patients with cirrhosis, with and without AD. RESULTS: The prevalence of PVT in patients with cirrhosis and AD was 9.36%, which was significantly higher than in patients with cirrhosis without AD (5.24%) (P = .04). Among patients with cirrhosis and AD, 63.37% developed PVT recently (the first detected PVT with no indication of chronic PVT). Compared with patients without PVT, a significantly higher proportion of patients with PVT had variceal bleeding (47.33% vs 19.63%; P < .001) and patients with PVT had a significantly higher median serum level of D-dimer (2.07 vs 1.25; P < .001). Splenectomy and endoscopic sclerotherapy were independent risk factors for PVT in patients with cirrhosis and AD. The 1-year mortality rate did not differ significantly between patients with vs without PVT. CONCLUSIONS: In an analysis of data from 2826 patients with cirrhosis, a significantly higher proportion of those with AD had PVT than those without AD. PVT was associated with increased variceal bleeding, which would increase the risk for AD. Strategies are needed to prevent PVT in patients with cirrhosis, through regular screening, to reduce portal hypertension. ClinicalTrials.gov no: NCT02457637 and NCT03641872.

Clinical features and outcomes of bacterascites in cirrhotic patients: A retrospective, multicentre study.

BACKGROUND & AIMS: Current guidelines on the management of bacterascites are limited. This multicentre, retrospective study investigated the clinical features and outcomes of cirrhosis patients with bacterascites. METHODS: Two series of cirrhosis patients were evaluated. The first included 418 patients with ascites-positive cultures at 11 hospitals during 2012-2018. Clinical characteristics and outcomes were recorded. The second included 208 patients with sterile ascites from a prospective cohort (NCT02457637). Clinical features and outcomes of cirrhotic patients with or without bacterascites were investigated. RESULTS: In the first series, bacterascites was diagnosed in 254/418 (60.8%) patients, and culture-positive spontaneous bacterial peritonitis (SBP) in 164/418 (39.2%) patients. Gram-positive bacteria were more prevalent in bacterascites patients than in culture-positive SBP patients (59.1% vs 22.0%; P < .001). For patients with acute-on-chronic liver failure (ACLF) in bacterascites and culture-positive SBP groups, the 28-day transplant-free mortality (41.3% vs 65.5%; P = .015) and the prevalence of in-hospital acute kidney injury (AKI) (84.8% vs 75%; P = .224). For patients without ACLF in the bacterascites (n = 208) and culture-positive SBP groups (n = 108), the 28-day transplant-free mortalities were 13% vs 13.9% (P = .822), the probabilities of progression to ACLF within 28 days were 10.1% vs 14.8% (P = .216) and the prevalences of in-hospital AKI were 14.4% vs 30.6% (P = .001). Bacterascites patients had higher 28-day mortality than those patients with sterile ascites, after propensity score matching (18.4% vs 8.6%; P = .010). CONCLUSION: Bacterascites patients had non-negligible poor clinical outcomes, including in-hospital AKI, progression to ACLF and 28-day mortality. Future studies are warranted to expedite the diagnosis of bacterascites and optimize antibiotic treatment.

TWIRLS, a knowledge-mining technology, suggests a possible mechanism for the pathological changes in the human host after coronavirus infection via ACE2.

Faced with the current large-scale public health emergency, collecting, sorting, and analyzing biomedical information related to the "SARS-CoV-2" should be done as quickly as possible to gain a global perspective, which is a basic requirement for strengthening epidemic control capacity. However, for human researchers studying viruses and hosts, the vast amount of information available cannot be processed effectively and in a timely manner, particularly if our scientific understanding is also limited, which further lowers the information processing efficiency. We present TWIRLS (Topic-wise inference engine of massive biomedical literatures), a method that can deal with various scientific problems, such as liver cancer, acute myeloid leukemia, and so forth, which can automatically acquire, organize, and classify information. Additionally, this information can be combined with independent functional data sources to build an inference system via a machine-based approach, which can provide relevant knowledge to help human researchers quickly establish subject cognition and to make more effective decisions. Using TWIRLS, we automatically analyzed more than three million words in more than 14,000 literature articles in only 4 hr. We found that an important regulatory factor angiotensin-converting enzyme 2 (ACE2) may be involved in host pathological changes on binding to the coronavirus after infection. On triggering functional changes in ACE2/AT2R, the cytokine homeostasis regulation axis becomes imbalanced via the Renin-Angiotensin System and IP-10, leading to a cytokine storm. Through a preliminary analysis of blood indices of COVID-19 patients with a history of hypertension, we found that non-ARB (Angiotensin II receptor blockers) users had more symptoms of severe illness than ARB users. This suggests ARBs could potentially be used to treat acute lung injury caused by coronavirus infection.

A patient with glycogen storage disease type Ia combined with chronic hepatitis B infection: a case report.

BACKGROUND: Glycogen storage disease type I (GSD I), also known as von Gierk disease, is a metabolic disorder leading to the excessive accumulation of glycogen and fat in organs, characterized by hepatomegaly, hypoglycemia, lactic acidemia, hyperlipidemia, hyperuricemia, puberty delay and growth retardation, which can be indicated by height, weight, blood glucose and blood lipids. CASE PRESENTATION: Here we present a 16-year-old male patient with GSD Ia complicated with hepatic adenoma and combined with hepatitis B. As a chronic hepatitis B patient, the patient was admitted to hospital in order to further clarify the nature of hepatic space occupancy because of suspicion of hepatocellular carcinoma. However, the imaging studies did not support hepatocellular carcinoma certainly. And by tracing his clinical history, we suggested that he might suffer from GSD I. Finally the diagnosis was confirmed by MRI (Gd-EOB-DTPA), liver biopsy and whole exome sequencing (WES). The WES discovered a homozygous point mutation at the exon 5 of G6PC gene at 17th chromosome, c.G648 T (p.L216 L, NM_000151, rs80356484). This pathogenic mutation causes CTG changing to CTT at protein 216. Though both codons encode leucine, this silent mutation creates a new splicing site 91 bp downstream of the authentic splice site. According to previous research, this mutation is a disease causal variant for GSD Ia, and has a high frequency among GSD patients in China and Japan. This patient was finally diagnosed as GSD Ia complicated with hepatic adenoma and combined with chronic hepatitis B, and received corn starch therapy immediately after GSD was suspected. After receiving corn starch therapy, the height and weight of the patient were increased, and the secondary sexual characteristics were developed, including beard, pubic hair and seminal emission. Unexpectedly, the liver adenomas were still increasing, and we did not find any cause to explain this phenomenon. CONCLUSION: This patient was diagnosed as GSD Ia combined with chronic hepatitis B, who responded to corn starch intervention. For childhood patients with hypoglycaemia, hyperlipidemia, puberty delay and growth retardation, GSD should be considered. Gene sequencing is valuable for the quick identification of GSD subtypes.

Genome-wide association study identifies HLA-DR variants conferring risk of HBV-related acute-on-chronic liver failure.

OBJECTIVE: Acute-on-chronic liver failure (ACLF) is an extreme condition after severe acute exacerbation of chronic hepatitis B; however, the underlying genetic factors involved in its onset and progression are currently unclear. DESIGN: We carried out a genome-wide association study among 399 HBV-related ACLFs (cases) and 401 asymptomatic HBV carriers (AsCs, as controls) without antiviral treatment. The initial findings were replicated in four independent case-control sets (a total of 901 ACLFs and 1686 AsCs). The roles of risk variants on clinical traits of ACLF were also analysed. RESULTS: Among 1300 ACLFs and 2087 AsCs, we identified rs3129859 at human leucocyte antigen (HLA) class II region (chromosome 6p21.32) associated with HBV-related ACLF (combined P dominant =2.64×10-20, OR=1.83). Analysis identified HLA-DRB1*12:02 as the top susceptible HLA allele associated with ACLF (p=3.94×10-6, OR=2.05). The association of rs3129859 was robust in ACLF subgroups (ACLFs with liver cirrhosis, p=1.36×10-16; ACLFs without liver cirrhosis, p=1.52×10-7), and patients at low-replicative phase (p=6.36×10-11, OR=2.29) or HBV e antigen-negative chronic hepatitis B phase (p=1.51×10-14, OR=1.86). Clinical traits analysis in patients with ACLF showed that the risky rs3129859*C allele was also associated with prolonged prothrombin time, faster progression to ascites development and higher 28-day mortality. CONCLUSIONS: Our genome-wide association study identified HLA-DR as the major locus for susceptibility to HBV-related ACLF. Our findings highlight the importance of HLA class II restricted CD4+ T-cell pathway on the immunopathogenesis of HBV-related ACLF.

Analysis of T cell receptor repertoire in monozygotic twins concordant and discordant for chronic hepatitis B infection.

Due to their identical inheritance and shared surroundings, identical twins have been the recommended group for studying the susceptibility and prognosis of diseases. Here, CD8+ T cell receptor beta (TCRß) chains were analyzed by high-throughput sequencing in three pairs of healthy identical twins and chronic hepatitis B patients. The data showed a high level of similarity in the TCR repertoire of each pair in terms of average TCR Vß segment expression and frequency of the complementary determining region 3 (CDR3) pattern and skewed or oligoclonal clonotypes. Notably, the level of similarity in TCR Vß expression between the twins appeared to be independent of the consistency or inconsistency of chronic HBV infection, although the detailed CDR3 pattern and frequency were related to disease prognosis. There were more immunodominant clonotypes in patients with HBV antigen seroconversion, which showed an increased abundance. These immunodominant clonotypes may be used as favorable prognostic biomarkers and potential targets for immunotherapy. Thus, delineating the CD8+ T cell repertoire of identical twins with concordant chronic viral infections provides a promising means to screen protective TCR genes for immunotherapy.

A novel mutation in the BCHE gene and phenotype identified in a child with low butyrylcholinesterase activity: a case report.

BACKGROUND: Butyrylcholinesterase (BChE), an ester hydrolase produced mainly by the liver, hydrolyzes certain short-acting neuromuscular blocking agents, like succinylcholine and mivacurium that are widely used during anesthesia. Patients with BChE deficiency are possibly in danger of postanesthetic apnea. Hereditary BChE deficiency results from the mutations of BCHE gene located on chromosome 3, 3q26.1-q26.2, between nucleotides 165,490,692-165,555,260. CASE PRESENTATION: This study describes a novel mutation in a child with BChE deficiency. In general, this child appeared healthy and well-developed with a normal appearance. However, the results of Wechsler Intelligence Scale showed that the full-scale intelligence quotient (FIQ) was 53, classified into the group with the minor defect. The BChE activity was 32.0 U/L, considerably lower than the normal lower limit (reference range: 5000-12,000 U/L). Sanger sequencing showed that there were 2 mutations in the exon 2 of BCHE gene of this child. One is a heterozygous mutation rs764588882 (NM_000055.3: c.401_402insA, p.Asn134Lysfs*23). The other one is a heterozygous mutation (NM_000055.3: c.73A > T, p.Lys25Ter) that has never been reported before. The two mutations lead to a premature stop of transcription. CONCLUSIONS: Double heterozygous recessive mutations are the cause of BChE deficiency of this boy in this study, including a novel mutation c.73A > T. Intellectual disability is a new phenotype that is probably associated with this mutation.