[Human embryonic stem cells to rescue fulminant hepatic failure]

International audienc

Analysis of Mesencephalic Astrocyte-derived Neurotrophic Factor in Multiple Myeloma

International audienceBackground/Aim: Multiple myeloma (MM) is characterized by high production of immunoglobulins resulting in a constant source of endoplasmic reticulum (ER)-stress. Mesencephalic astrocyte-derived neurotrophic factor (MANF) was identified as a possible circulating biomarker that could help in monitoring ER-stress mediated diseases. Materials and Methods: To assess the relevance of MANF in MM, we performed in silico and in vitro analysis in malignant cell lines including the myeloma cell line RPMI 8226. Serum MANF concentration was compared between healthy subjects (n=60), patients with MM (n=68), or those with monoclonal gammopathy of undetermined significance (MGUS) (n=73). Results: MANF mRNA expression was upregulated in the RPMI 8226 cell line, and higher secretion of MANF was measured in RPMI 8226 supernatant. Serum MANF levels were not significantly different between MM or MGUS patients and those in age-and sex-matched healthy controls. Conclusion: MANF was not validated as a biomarker of interest in MM patients. Its potential implication in myeloma pathogenesis should be investigated

Investigation of omeprazole and phenacetin first-pass metabolism in humans using a microscale bioreactor and pharmacokinetic models

A new in vitro microfluidic platform (integrated insert dynamic microfluidic platform, IIDMP) allowing the co-culture of intestinal Caco-2 TC7 cells and of human primary hepatocytes was used to test the absorption and first-pass metabolism of two drugs: phenacetin and omeprazole. The metabolism of these drugs by CYP1A2, CYP2C19 and CYP3A4 was evaluated by the calculation of bioavailabilities and of intrinsic clearances using a pharmacokinetic (PK) model. To demonstrate the usefulness of the device and of the PK model, predictions were compared with in vitro and in vivo results from the literature. Based on the IIDMP experiments, hepatic in vivo clearances of phenacetin and omeprazole in the IIDMP were predicted to be 3.10 [+ or -] 0.36 and 1.46 [+ or -] 0.25 ml/min/kg body weight, respectively. This appeared lower than the in vivo observed data with values ranging between 11.9-19.6 and 5.8-7.5 ml/min/kg body weight, respectively. Then the calculated hepatic and intestinal clearances led to predicting an oral bioavailability of 0.85 and 0.77 for phenacetin and omeprazole versus 0.92 and 0.78 using separate data from the simple monoculture of Caco-2 TC7 cells and hepatocytes in Petri dishes. When compared with the in vivo data, the results of oral bioavailability were overestimated (0.37 and 0.71, respectively). The feasibility of co-culture in a device allowing the integration of intestinal absorption, intestinal metabolism and hepatic metabolism in a single model was demonstrated. Nevertheless, further experiments with other drugs are needed to extend knowledge of the device to predict oral bioavailability and intestinal first-pass metabolism

Performance Evaluation of the Access anti-HBc Total Assay on the DxI 9000 Access Immunoassay Analyzer

International audienceThis study evaluated the diagnostic and analytical performances of the Access anti-HBV core antigen (anti-HBc Total) assay on the DxI 9000 Access Immunoassay System (Beckman Coulter Inc.). The multicenter study involved both prospective and retrospective sample collection from non-selected blood donors, hospitalized patients, or presumed anti-HBc Total positive individuals. Fresh/previously-frozen samples were tested with the Access and comparator assays to determine concordance; discrepant samples were tested with a second CE-marked assay. Among the 5983 non-selected fresh blood donor samples deemed anti-HBc Total negative, clinical specificity of the Access assay was 99.58% (95%CI: 99.38–99.72%). Clinical specificity was 99.27% (97.37–99.80%) among 273 anti-HBc Total negative hospitalized patient samples. Clinical sensitivity on 450 anti-HBc Total positive samples was 99.78% (98.75–99.96%). Evaluation in seroconversion panels revealed an average 1.4-day earlier detection versus a comparator assay. The Access assay demonstrated excellent clinical and analytical performances comparable to existing CE-marked anti-HBc Total assays. NCT04904835

Performance evaluation of the Access HBsAg and Access HBsAg confirmatory assays on the DxI 9000 Access immunoassay analyzer

International audienceIntroductionThis study evaluated the clinical and analytical performances of the Access HBsAg and the Access HBsAg Confirmatory assays on the DxI 9000 Access Immunoassay Analyzer (Beckman Coulter, Inc.).Materials and methodsDiagnostic specificity and sensitivity of the Access HBsAg and Access HBsAg Confirmatory assays were evaluated by comparing the Access assays to the final HBsAg sample status determined using the Architect, PRISM, or Elecsys HBsAg assays, along with Architect or PRISM HBsAg Confirmatory assays. Imprecision, sensitivity on seroconversion panels, analytical sensitivity on WHO, and recognition of HBV variants were also evaluated.ResultsA total of 7534 samples were included in the analysis (6047 blood donors, 1032 hospitalized patients, 455 positive patients’ samples). Access HBsAg assay sensitivity and specificity were at 100.00% (99.19–100.0) and 99.92% (99.82–99.97), respectively. Sensitivity of Access HBsAg Confirmatory assay was 100.00% (99.21–100.0) on the 464 HBsAg positive samples. The use of a high positive algorithm for the Access HBsAg assay, wherein samples with S/CO ≥ 100.00 were considered positive without requiring repeat or confirmatory testing, was successfully evaluated with all 450 specimens with S/CO greater than 100.00 (sensitivity 100.00%; 99.19–100.0). Access HBsAg assay demonstrated good analytical performance, equivalent recognition of seroconversion panels compared to Architect assay, and an analytical sensitivity between 0.022 and 0.025 IU/mL. All HBV genotypes, subtypes and mutants were well detected without analytical sensitivity loss.ConclusionAccess HBsAg and Access HBsAg Confirmatory assays demonstrated robust performances. They provide low samples volume requirements and a simplified process, no systematic retesting for high positive samples

Correction: Permissivity of Primary Human Hepatocytes and Different Hepatoma Cell Lines to Cell Culture Adapted Hepatitis C Virus.

[This corrects the article DOI: 10.1371/journal.pone.0070809.]

Permissivity of primary human hepatocytes and different hepatoma cell lines to cell culture adapted hepatitis C virus.

Significant progress has been made in Hepatitis C virus (HCV) culture since the JFH1 strain cloning. However, developing efficient and physiologically relevant culture systems for all viral genotypes remains an important goal. In this work, we aimed at producing a high titer JFH1 derived virus to test different hepatic cells' permissivity. To this end, we performed successive infections and obtained a JFH1 derived virus reaching high titers. Six potential adaptive mutations were identified (I599V in E2, R1373Q and M1611T in NS3, S2364P and C2441S in NS5A and R2523K in NS5B) and the effect of these mutations on HCV replication and infectious particle production was investigated. This cell culture adapted virus enabled us to efficiently infect primary human hepatocytes, as demonstrated using the RFP-NLS-IPS reporter protein and intracellular HCV RNA quantification. However, the induction of a strong type III interferon response in these cells was responsible for HCV inhibition. The disruption of this innate immune response led to a strong infection enhancement and permitted the detection of viral protein expression by western blotting as well as progeny virus production. This cell culture adapted virus also enabled us to easily compare the permissivity of seven hepatoma cell lines. In particular, we demonstrated that HuH-7, HepG2-CD81, PLC/PRF/5 and Hep3B cells were permissive to HCV entry, replication and secretion even if the efficiency was very low in PLC/PRF/5 and Hep3B cells. In contrast, we did not observe any infection of SNU-182, SNU-398 and SNU-449 hepatoma cells. Using iodixanol density gradients, we also demonstrated that the density profiles of HCV particles produced by PLC/PRF/5 and Hep3B cells were different from that of HuH-7 and HepG2-CD81 derived virions. These results will help the development of a physiologically relevant culture system for HCV patient isolates

The french Chronic Kidney Disease-Renal Epidemiology and Information Network (CKD-REIN) cohort study : to better understand chronic kidney disease

International audienc

Machine Learning-Based Urine Peptidome Analysis to Predict and Understand Mechanisms of Progression to Kidney Failure

International audienceIntroduction: The identification of patients with chronic kidney disease (CKD) at risk of progressing to kidney failure (KF) is important for clinical decision-making. In this study we assesed whether urinary peptidome (UP) analysis may help classify patients with CKD and improve KF risk prediction. Methods: The UP was analyzed using capillary electrophoresis coupled to mass spectrometry in a case-cohort sample of 1000 patients with CKD stage G3 to G5 from the French CKD-Renal Epidemiology and Information Network (REIN) cohort. We used unsupervised and supervised machine learning to classify patients into homogenous UP clusters and to predict 3-year KF risk with UP, respectively. The predictive performance of UP was compared with the KF risk equation (KFRE), and evaluated in an external cohort of 326 patients. Results: More than 1000 peptides classified patients into 3 clusters with different CKD severities and etiologies at baseline. Peptides with the highest discriminative power for clustering were fragments of proteins involved in inflammation and fibrosis, highlighting those derived from α-1-antitrypsin, a major acute phase protein with anti-inflammatory and antiapoptotic properties, as the most significant. We then identified a set of 90 urinary peptides that predicted KF with a c-index of 0.83 (95% confidence interval [CI]: 0.81−0.85) in the case-cohort and 0.89 (0.83−0.94) in the external cohort, which were close to that estimated with the KFRE (0.85 [0.83−0.87]). Combination of UP with KFRE variables did not further improve prediction. Conclusion: This study shows the potential of UP analysis to uncover new pathophysiological CKD progression pathways and to predict KF risk with a performance equal to that of the KFRE