Serological response and breakthrough infection after COVID-19 vaccination in patients with cirrhosis and post-liver transplant.

BACKGROUND: Vaccine hesitancy and lack of access remain major issues in disseminating COVID-19 vaccination to liver patients globally. Factors predicting poor response to vaccination and risk of breakthrough infection are important data to target booster vaccine programs. The primary aim of the current study was to measure humoral responses to 2 doses of COVID-19 vaccine. Secondary aims included the determination of factors predicting breakthrough infection. METHODS: COVID-19 vaccination and Biomarkers in cirrhosis And post-Liver Transplantation is a prospective, multicenter, observational case-control study. Participants were recruited at 4-10 weeks following first and second vaccine doses in cirrhosis [n = 325; 94% messenger RNA (mRNA) and 6% viral vaccine], autoimmune liver disease (AILD) (n = 120; 77% mRNA and 23% viral vaccine), post-liver transplant (LT) (n = 146; 96% mRNA and 3% viral vaccine), and healthy controls (n = 51; 72% mRNA, 24% viral and 4% heterologous combination). Serological end points were measured, and data regarding breakthrough SARS-CoV-2 infection were collected. RESULTS: After adjusting by age, sex, and time of sample collection, anti-Spike IgG levels were the lowest in post-LT patients compared to cirrhosis (p < 0.0001), AILD (p < 0.0001), and control (p = 0.002). Factors predicting reduced responses included older age, Child-Turcotte-Pugh B/C, and elevated IL-6 in cirrhosis; non-mRNA vaccine in AILD; and coronary artery disease, use of mycophenolate and dysregulated B-call activating factor, and lymphotoxin-α levels in LT. Incident infection occurred in 6.6%, 10.6%, 7.4%, and 15.6% of cirrhosis, AILD, post-LT, and control, respectively. The only independent factor predicting infection in cirrhosis was low albumin level. CONCLUSIONS: LT patients present the lowest response to the SARS-CoV-2 vaccine. In cirrhosis, the reduced response is associated with older age, stage of liver disease and systemic inflammation, and breakthrough infection with low albumin level.

Frailty in outpatients with cirrhosis: A prospective observational study.

BACKGROUND AND AIM: Frailty is increasingly recognized as a major prognostic factor in cirrhosis in addition to conventional liver insufficiency scores. The aim was to compare the prevalence and characteristics of frailty between patients with cirrhosis and controls, and to analyse its prognostic value. METHODS: We included outpatients with cirrhosis and age- and gender-matched non-cirrhotic controls. Frailty was defined according to the Fried frailty criteria. In patients with cirrhosis, we analysed the ability of the degree of frailty to predict a composite endpoint, consisting of hospitalization, admission to a long-term care centre, falls or death. RESULTS: We included 135 patients with cirrhosis and 135 controls. The prevalence of frailty was higher among patients with cirrhosis: 35 (25.9%) frail, 74 (54.8%) pre-frail and 26 (19.2%) robust vs 14 (10.4%) frail, 67 (49.6%) pre-frail and 54 (40%) robust (P < .001) in controls. This difference was mainly as a result of decreased muscle strength in patients with cirrhosis. During follow-up, frail patients with cirrhosis showed a higher probability of composite endpoint, hospitalization and falls than pre-frail and robust cirrhotic patients but mortality was similar. MELD-Na score and frailty were independent predictive factors for hospitalization, frailty for falls, and MELD-Na score and albumin for survival. Vitamin D deficiency and increased cystatin C were associated with frailty. CONCLUSIONS: Frailty was more frequent in outpatients with cirrhosis than in controls, mainly because of a decrease in muscle strength, and it could be a predictive factor for hospitalization and falls in these patients.

MymA Bioactivated Thioalkylbenzoxazole Prodrug Family Active against Mycobacterium tuberculosis.

Screening of a GSK-proprietary library against intracellular Mycobacterium tuberculosis identified 1, a thioalkylbenzoxazole hit. Biological profiling and mutant analysis revealed that this compound is a prodrug that is bioactivated by the mycobacterial enzyme MymA. A hit-expansion program including design, synthesis, and profiling of a defined set of analogues with optimized drug-like properties led to the identification of an emerging lead compound, displaying potency against intracellular bacteria in the low micromolar range, high in vitro solubility and permeability, and excellent microsomal stability.

Optimization of Hydantoins as Potent Antimycobacterial Decaprenylphosphoryl-ß-d-Ribose Oxidase (DprE1) Inhibitors.

In search of novel drugs against tuberculosis, we previously discovered and profiled a novel hydantoin-based family that demonstrated highly promising in vitro potency against Mycobacterium. tuberculosis. The compounds were found to be noncovalent inhibitors of DprE1, a subunit of decaprenylphosphoryl-ß-d-ribose-2'-epimerase. This protein, localized in the periplasmic space of the mycobacterial cell wall, was shown to be an essential and vulnerable antimycobacterial drug target. Here, we report the further SAR exploration of this chemical family through more than 80 new analogues. Among these, the most active representatives combined submicromolar cellular potency and nanomolar target affinity with balanced physicochemical properties and low human cytotoxicity. Moreover, we demonstrate in vivo activity in an acute Mtb infection model and provide further proof of DprE1 being the target of the hydantoins. Overall, the hydantoin family of DprE1 inhibitors represents a promising noncovalent lead series for the discovery of novel antituberculosis agents.

Effect of a Multistrain Probiotic on Cognitive Function and Risk of Falls in Patients With Cirrhosis: A Randomized Trial.

Probiotics can modulate gut microbiota, intestinal permeability, and immune response and could therefore improve cognitive dysfunction and help avoid potential consequences, such as falls, in patients with cirrhosis. The aim of this study was to evaluate the effect of a multistrain probiotic on cognitive function, risk of falls, and inflammatory response in patients with cirrhosis. Consecutive outpatients with cirrhosis and cognitive dysfunction (defined by a Psychometric Hepatic Encephalopathy Score [PHES] < -4) and/or falls in the previous year were randomized to receive either a sachet of a high-concentration multistrain probiotic containing 450 billion bacteria twice daily for 12 weeks or placebo. We evaluated the changes in cognitive function (PHES); risk of falls (Timed Up and Go [TUG] test, gait speed, and incidence of falls); systemic inflammatory response; neutrophil oxidative burst; intestinal barrier integrity (serum fatty acid-binding protein 6 [FABP-6] and 2 [FABP-2] and zonulin and urinary claudin-3); bacterial translocation (lipopolysaccharide-binding protein [LBP]); and fecal microbiota. Thirty-six patients were included. Patients treated with the probiotic (n = 18) showed an improvement in the PHES (P = 0.006), TUG time (P = 0.015) and gait speed (P = 0.02), and a trend toward a lower incidence of falls during follow-up (0% compared with 22.2% in the placebo group [n = 18]; P = 0.10). In the probiotic group, we observed a decrease in C-reactive protein (P = 0.01), tumor necrosis factor alpha (P = 0.01), FABP-6 (P = 0.009), and claudin-3 (P = 0.002), and an increase in poststimulation neutrophil oxidative burst (P = 0.002). Conclusion: The multistrain probiotic improved cognitive function, risk of falls, and inflammatory response in patients with cirrhosis and cognitive dysfunction and/or previous falls.

Identification and Profiling of Hydantoins-A Novel Class of Potent Antimycobacterial DprE1 Inhibitors.

Tuberculosis is the leading cause of death worldwide from infectious diseases. With the development of drug-resistant strains of Mycobacterium tuberculosis, there is an acute need for new medicines with novel modes of action. Herein, we report the discovery and profiling of a novel hydantoin-based family of antimycobacterial inhibitors of the decaprenylphospho-ß-d-ribofuranose 2-oxidase (DprE1). In this study, we have prepared a library of more than a 100 compounds and evaluated them for their biological and physicochemical properties. The series is characterized by high enzymatic and whole-cell activity, low cytotoxicity, and a good overall physicochemical profile. In addition, we show that the series acts via reversible inhibition of the DprE1 enzyme. Overall, the novel compound family forms an attractive base for progression to further stages of optimization and may provide a promising drug candidate in the future.

Ascitic fluid regulates the local innate immune response of patients with cirrhosis.

Ascitic neutrophils from cirrhotic patients with spontaneous bacterial peritonitis (SBP) exhibit an impaired oxidative burst that could facilitate bacterial infection. However, the influence of the cell-free ascitic fluid of these patients on neutrophil function has not been investigated. To analyze this influence, we determined the ascitic levels of cytokines, resistin, and lactoferrin and their association with neutrophil function, disease severity score, and SBP resolution. We analyzed NETosis induction by microscopy and oxidative burst by the flow cytometry of healthy neutrophils cultured in ascitic fluid from cirrhotic patients with sterile ascites (SA) and with SBP before and after antibiotic treatment. Resistin, IL-6, IL-1 receptor antagonist, IL-1ß, and lactoferrin levels were measured in ascitic fluids and supernatants of cultured neutrophils and PBMCs by ELISA. Upon stimulation, healthy neutrophils cultured in SBP ascitic fluid produced lower NETosis and oxidative burst than those cultured in SA. Ascitic resistin levels were negatively correlated with NETosis, oxidative burst, and ascitic glucose levels; and positively correlated with the model for end-stage liver disease score. After an E. coli or TNF-α stimulus, neutrophils were the major resistin producers. Resistin indirectly reduced the oxidative burst of neutrophils and directly reduced the inflammatory phenotype of monocytes and TNF-α production. Bacterial-induced resistin production can down-regulate the inflammatory response of macrophages and neutrophil function in ascitic fluid. Consequently, this down-regulation may jeopardize the elimination of bacteria that translocate to ascitic fluid in patients with cirrhosis.

Toll-like receptor 4 polymorphisms and bacterial infections in patients with cirrhosis and ascites.

AIM: To assess the relationship between the presence of toll-like receptor 4 (TLR4) polymorphisms and bacterial infections in cirrhotic patients with ascites. METHODS: We prospectively included consecutive patients with cirrhosis and ascites hospitalized during a 6-year period. Patients with human immunodeficiency virus (HIV) infection or any other immunodeficiency, patients with advanced hepatocellular carcinoma (beyond Milan's criteria) or any other condition determining poor short-term prognosis, and patients with a permanent urinary catheter were excluded. The presence of D299G and/or T399I TLR4 polymorphisms was determined by sequencing and related to the incidence and probability of bacterial infections, other complications of cirrhosis, hepatocellular carcinoma, and mortality during follow-up. A multivariate analysis to identify predictive variables of mortality in the whole series was performed. RESULTS: We included 258 patients: 28 (10.8%) were carriers of D299G and/or T399I TLR4 polymorphisms (polymorphism group) and 230 patients were not (wild-type group). The probability of developing any bacterial infection at one-year follow-up was 78% in the polymorphism group and 69% in the wild-type group (P = 0.54). The one-year probability of presenting infections caused by gram-negative bacilli (51% vs 44%, P = 0.68), infections caused by gram-positive cocci (49% vs 40%, P = 0.53), and spontaneous bacterial peritonitis (29% vs 34%, respectively, P = 0.99) did not differ between the two groups. The one-year probability of transplant-free survival was 55% in the polymorphism group and 66% in the wild-type group (P = 0.15). Multivariate analysis confirmed that age, Child-Pugh score, active alcohol intake, previous hepatic encephalopathy, hepatocellular carcinoma and serum creatinine were associated with a higher risk of death during follow-up. CONCLUSION: Genetic polymorphisms D299G and/or T399I of TLR4 do not seem to play a relevant role in the predisposition of cirrhotic patients with ascites to bacterial infections.

Killer Immunoglobulin-Like Receptor Profiles Are not Associated with Risk of Amoxicillin-Clavulanate-Induced Liver Injury in Spanish Patients.

Natural killer cells are an integral part of the immune system and represent a large proportion of the lymphocyte population in the liver. The activity of these cells is regulated by various cell surface receptors, such as killer Ig-like receptors (KIR) that bind to human leukocyte antigen (HLA) class I ligands on the target cell. The composition of KIR receptors has been suggested to influence the development of specific diseases, in particularly autoimmune diseases, cancer and reproductive diseases. The role played in idiosyncratic drug-induced liver injury (DILI) is currently unknown. In this study, we examined KIR gene profiles and HLA class I polymorphisms in amoxicillin-clavulanate (AC) DILI patients in search for potential risk associations. One hundred and two AC DILI patients and 226 controls were genotyped for the presence or absence of 16 KIR loci, including the two pseudogenes 2DP1 and 3DP1. No significant differences were found in the distribution of individual KIRs between patients and controls, which were comparable to previously reported KIR data from ethnically similar cohorts. The 21.6 and 21.2% of the patients and controls, respectively, were homozygous haplotype A carriers, while 78.4 and 78.8%, respectively, contained at least one B haplotype (Bx). The genotypes translated into 27 (AC DILI) and 46 (controls) different gene profiles, with 19 being present in both groups. The most frequent Bx gene profile containing KIRs 2DS2, 2DL2, 2DL3, 2DP1, 2DL1, 3DL1, 2DS4, 3DL2, 3DL3, 2DL4, and 3PD1 was present in 16% of the DILI patients and 14% of the controls. The distribution of HLA class I epitopes did not differ significantly between AC DILI patients and controls. The most frequent receptor-ligand combinations in the DILI patients were 2DL3 + epitope C1 (67%) and 3DL1 + Bw4 motif (67%), while 2DL1 + epitope C2 (69%) and 3DL1 + Bw4 motif (69%) predominated in the controls. This is to our knowledge the first analysis of KIR receptor-HLA ligand associations in DILI, although our findings do not support evidence of these genetic variations playing a major role in AC DILI development.

Release of 50 new, drug-like compounds and their computational target predictions for open source anti-tubercular drug discovery.

As a follow up to the antimycobacterial screening exercise and the release of GSK´s first Tres Cantos Antimycobacterial Set (TCAMS-TB), this paper presents the results of a second antitubercular screening effort of two hundred and fifty thousand compounds recently added to the GSK collection. The compounds were further prioritized based on not only antitubercular potency but also on physicochemical characteristics. The 50 most attractive compounds were then progressed for evaluation in three different predictive computational biology algorithms based on structural similarity or GSK historical biological assay data in order to determine their possible mechanisms of action. This effort has resulted in the identification of novel compounds and their hypothesized targets that will hopefully fuel future TB drug discovery and target validation programs alike.

Impaired innate immune response of leukocytes from ascitic fluid of patients with spontaneous bacterial peritonitis.

An ascitic microenvironment can condition the immune response of cells from cirrhotic patients with spontaneous bacterial peritonitis. To characterize this response, we determined the cytokine concentrations in ascitic fluid and analyzed the phenotype and function of ascitic leukocytes at diagnosis and after antibiotic-induced resolution in sterile ascites and ascitic fluid of 2 spontaneous bacterial peritonitis variants: positive and negative bacteriological culture. At diagnosis, a high concentration was found of IL-6 and IL-10 in the ascitic fluid from negative and positive bacteriological culture. The IL-6 concentration correlated with the percentage of neutrophils (R = 0.686, P < 0.001). In this context, positive and negative culture neutrophils had an impaired oxidative burst, and, after the antibiotic, the negative culture spontaneous bacterial peritonitis burst was fully recovered. Higher concentrations of IL-6 and IL-10 correlated with the presence of low granular CD 14(low) macrophages (R = -0.436, P = 0.005 and R = 0.414, P = 0.007, respectively). Positive culture spontaneous bacterial peritonitis macrophages expressed the lowest levels of CD16, CD86, CD11b and CD206, and HLA-DR, suggesting an impaired global function. Treatment increased all markers on the positive culture macrophages and CD11b and CD86 on negative culture macrophages. In negative culture spontaneous bacterial peritonitis, this increase was accompanied by phagocytic function recovery. The antibiotics then reverted the marker levels on positive and negative culture macrophages to the levels on sterile ascitis macrophages and restored ascitic negative culture cell function.

Design, synthesis, and evaluation of new thiadiazole-based direct inhibitors of enoyl acyl carrier protein reductase (InhA) for the treatment of tuberculosis.

Mycobacterial enoyl acyl carrier protein reductase (InhA) is a clinically validated target for the treatment of tuberculosis infections, a disease that still causes the death of at least a million people annually. A known class of potent, direct, and competitive InhA inhibitors based on a tetracyclic thiadiazole structure has been shown to have in vivo activity in murine models of tuberculosis infection. On the basis of this template, we have here explored the medicinal chemistry of truncated analogues that have only three aromatic rings. In particular, compounds 8b, 8d, 8f, 8l, and 8n show interesting features, including low nanomolar InhA IC50, submicromolar antimycobacterial potency, and improved physicochemical profiles in comparison with the tetracyclic analogues. From this series, 8d is identified as having the best balance of potency and properties, whereby the resolved 8d S-enatiomer shows encouraging in vivo efficacy.

Cytokine production in patients with cirrhosis and TLR4 polymorphisms.

AIM: To analyze the cytokine production by peripheral blood cells from cirrhotic patients with and without TLR4 D299G and/or T399I polymorphisms. METHODS: The study included nine patients with cirrhosis and TLR4 D299G and/or T399I polymorphisms, and 10 wild-type patients matched for age, sex and degree of liver failure. TLR4 polymorphisms were determined by sequence-based genotyping. Cytokine production by peripheral blood cells was assessed spontaneously and also after lipopolysaccharide (LPS) and lipoteichoic acid (LTA) stimulation. RESULTS: Patients with TLR4 polymorphisms had a higher incidence of previous hepatic encephalopathy than wild-type patients (78% vs 20%, P = 0.02). Spontaneous production of interleukin (IL)-6 and IL-10 was lower in patients with TLR4 polymorphisms than in wild-type patients [IL-6: 888.7 (172.0-2119.3) pg/mL vs 5540.4 (1159.2-26053.9) pg/mL, P < 0.001; IL-10: 28.7 (6.5-177.1) pg/mL vs 117.8 (6.5-318.1) pg/mL, P = 0.02]. However, the production of tumor necrosis factor-α, IL-6 and IL-10 after LPS and LTA stimulation was similar in the two groups. CONCLUSION: TLR4 polymorphisms were associated with a distinctive pattern of cytokine production in cirrhotic patients, suggesting that they play a role in the development of cirrhosis complications.

Effects of intravenous albumin in patients with cirrhosis and episodic hepatic encephalopathy: a randomized double-blind study.

BACKGROUND & AIMS: Episodic hepatic encephalopathy is frequently precipitated by factors that induce circulatory dysfunction, cause oxidative stress-mediated damage or enhance astrocyte swelling. The administration of albumin could modify these factors and improve the outcome of hepatic encephalopathy. The aim of this study is to assess the efficacy of albumin in a multicenter, prospective, double-blind, controlled trial (ClinicalTrials.gov number, NCT00886925). METHODS: Cirrhotic patients with an acute episode of hepatic encephalopathy (grade II-IV) were randomized to receive albumin (1.5g/kg on day 1 and 1.0g/kg on day 3) or isotonic saline, in addition to the usual treatment (laxatives, rifaximin 1200mg per day). The primary end point was the proportion of patients in which encephalopathy was resolved on day 4. The secondary end points included survival, length of hospital stay, and biochemical parameters. RESULTS: Fifty-six patients were randomly assigned to albumin (n=26) or saline (n=30) stratified by the severity of HE. Both groups were comparable regarding to demographic data, liver function, and precipitating factors. The percentage of patients without hepatic encephalopathy at day 4 did not differ between both groups (albumin: 57.7% vs. saline: 53.3%; p>0.05). However, significant differences in survival were found at day 90 (albumin: 69.2% vs. saline: 40.0%; p=0.02). CONCLUSIONS: Albumin does not improve the resolution of hepatic encephalopathy during hospitalization. However, differences in survival after hospitalization suggest that the development of encephalopathy may identify a subgroup of patients with advanced cirrhosis that may benefit from the administration of albumin.

Secondary bacterial peritonitis in cirrhosis: a retrospective study of clinical and analytical characteristics, diagnosis and management.

BACKGROUND & AIMS: Secondary bacterial peritonitis in cirrhotic patients is an uncommon entity that has been little reported. Our aim is to analyse the frequency, clinical characteristics, treatment and prognosis of patients with secondary peritonitis in comparison to those of patients with spontaneous bacterial peritonitis (SBP). METHODS: Retrospective analysis of 24 cirrhotic patients with secondary peritonitis compared with 106 SBP episodes. RESULTS: Secondary peritonitis represented 4.5% of all peritonitis in cirrhotic patients. Patients with secondary peritonitis showed a significantly more severe local inflammatory response than patients with SBP. Considering diagnosis of secondary peritonitis, the sensitivity of Runyon's criteria was 66.6% and specificity 89.7%, Runyon's criteria and/or polymicrobial ascitic fluid culture were present in 95.6%, and abdominal computed tomography was diagnostic in 85% of patients in whom diagnosis was confirmed by surgery or autopsy. Mortality during hospitalization was higher in patients with secondary peritonitis than in those with SBP (16/24, 66.6% vs. 28/106, 26.4%) (p<0.001). There was a trend to lower mortality in secondary peritonitis patients who underwent surgery (7/13, 53.8%) than in those who received medical treatment only (9/11, 81.8%) (p=0.21). Considering surgically treated patients, the time between diagnostic paracentesis and surgery was shorter in survivors than in non-survivors (3.2+/-2.4 vs. 7.2+/-6.1 days, p=0.31). CONCLUSIONS: Secondary peritonitis is an infrequent complication in cirrhotic patients but mortality is high. A low threshold of suspicion on the basis of Runyon's criteria and microbiological data, together with an aggressive approach that includes prompt abdominal computed tomography and early surgical evaluation, could improve prognosis in these patients.