Institute Of Recherche En Biotherapie

Montpellier, France

Institute Of Recherche En Biotherapie

Montpellier, France
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Tuaillon E.,Montpellier University | Tuaillon E.,Institute Of Recherche En Biotherapie | Mondain A.-M.,CHRU de Montpellier | Nagot N.,Montpellier University | And 9 more authors.
PLoS ONE | Year: 2012

Background: The decline in hepatitis B virus surface antigen (HBsAg) may be an early predictor of the viral efficacy of Hepatitis B virus (HBV) therapy. The HBsAg levels obtained by different immunoassays now need comparing and the relationships between levels of HBsAg and HBV DNA alongside HBsAg and genotype must be evaluated. Methodology/Principal Findings: HBsAg levels were compared among 80 patients using the Abbott Architect assay, a commercial immunoassay approved for HBsAg detection and quantitation, and three other assays derived from immunoassays approved for HBsAg detection (manufactured by Diasorin, Bio-Rad and Roche). Good correlation was found between the Abbot vs. Diasorin, Bio-Rad and Roche assays with narrow 95% limits of agreement and small mean differences: -0.06 to 0.11, -0.09 log 10 IU/mL; -0.57 to 0.64, -0.04 log 10 IU/mL; -0.09 to 0.45, -0.27 log 10 IU/mL, respectively. These agreements were not affected by genotypes A or D. HBsAg was weakly correlated with HBV DNA, whatever the HBsAg assay used: Abbott, ρ = 0.36 p = 0.001, Diasorin ρ = 0.34, p = 0.002; Bio-Rad ρ = 0.37, p<0.001; or Roche ρ = 0.41, p<0.001. This relationship between levels of HBsAg and HBV DNA seemed to depend on genotypes. Whereas HBsAg (Abbott assay) tended to correlate with HBV DNA for genotype A (ρ = 0.44, p = 0.02), no such correlation was significant for genotypes D (ρ = 0.29, p = 0.15). Conclusion/Significance: The quantitation of HBsAg in routine clinical samples is comparable between the reference assay and the adapted assays with acceptable accuracy limits, low levels of variability and minimum discrepancy. While HBsAg quantitation is not affected by HBV genotype, the observed association between levels of HBsAg and HBV DNA seems genotype dependent. © 2012 Tuaillon et al.

Valea D.,Center Muraz | Valea D.,Institute Of Recherche En Science Of La Sante Dro | Tuaillon E.,Institute Of Recherche En Biotherapie | Tuaillon E.,Montpellier University Hospital Center | And 9 more authors.
Retrovirology | Year: 2011

Background: Transmission of human immunodeficiency virus type 1 (HIV-1) through breast-feeding may involve both cell-free and cell-associated virus. This latter viral reservoir remains, however, to be fully explored. CD4+T cell-associated virus production in breast milk was therefore investigated.Methods: The ex vivo spontaneous production of HIV-1 antigen and HIV-1 RNA by CD4+T cells was measured in paired blood and breast milk samples from 15 HIV-1 infected women treated or not with antiretroviral drugs. Spontaneous antigen secreting cells (HIV-1-AgSCs) from breast milk and blood were enumerated by an ELISpot assay, and cell-associated HIV-1 RNA was quantified by real-time PCR in supernatants of CD4+T cells cultured for 18 hours without addition of polyclonal activators.Results: Among the CD4+T cells present in breast milk, memory cells expressing high levels of cell-surface activation markers were predominant. Spontaneous HIV-1-AgSCs were detected and enumerated in the breast milk of all 15 women, with a median number of 13.0 and 9.5 HIV-1- AgSCs/106 CD4+T cells in aviremic (n = 7) and viremic (n = 8) women, respectively. Cell- associated HIV-1 RNA was detected in cell-free supernatants from 4/7 aviremic and 5/8 viremic individuals at median levels of 190 and 245 copies/ml, respectively.Conclusions: Activated CD4+T cells producing HIV-1 are detected in the breast milk of untreated individuals as well as those receiving highly active antiretroviral therapy. This finding strongly suggests that HIV-1 replication occurs in latently infected CD4+T cells that, upon spontaneous activation, revert to productively infected cells. These cells might be responsible for a residual breast milk transmission despite maternal highly active antiretroviral therapy. © 2011 Valea et al; licensee BioMed Central Ltd.

Attaoua C.,Montpellier University | Vincent L.-A.,Montpellier University | Abdel Jaoued A.,Montpellier University | Hadj-Kaddour K.,Montpellier University | And 5 more authors.
Fundamental and Clinical Pharmacology | Year: 2015

On account of its extreme intrinsic resistance to apoptosis and of its strong ability to become chemoresistant after a primary response to drugs, malignant melanoma (MM) is still a therapeutic challenge. We previously showed that glutathione S-transferase mu 1 (GSTM1) acts in synergy with multidrug resistance protein 1 (MRP1) to protect GSTM1-transfected human CAL1 melanoma cells from toxic effects of vincristine (VCR). Herein, we investigated the role of these proteins in the acquired resistance of CAL1 cells to vinca alkaloids (VAs). Resistant lines were established by continuous exposure (>1 year) of parental CAL1-wt cells to VCR, vindesine (VDS), or vinorelbine (VRB): CAL1R-VCR, CAL1R-VDS, CAL1R-VRB, respectively. All resistant lines displayed more than 10-fold increase in resistance to their selection VA, and specifically expressed GSTM1. Suggesting a direct interaction between this protein and VAs, each VA specifically decreased the GSTM1-mediated glutathione conjugation activity in cell lysates. Curcumin (GSTM1 inhibitor), BSO (glutathione synthesis inhibitor), and MK571 (MRP1 inhibitor) considerably reversed the acquired resistance to VCR and VDS, but not to VRB. Microarray data analysis revealed similar gene expression patterns of CAL1R-VCR and CAL1R-VDS, and a distinct one for CAL1R-VRB. These data suggest a differential involvement of GSTM1 and MRP1 in acquired resistance to VAs. A coordinated expression and activity of GSTM1 and MRP1 is required to protect CAL1 cells from VCR and VDS, while the simple expression of GSTM1 is sufficient, possibly by a direct drug/protein interaction, to confer resistance against VRB. © 2014 Société Française de Pharmacologie et de Thérapeutique.

Vossier L.,Laboratoire TransDiag | Leon F.,Laboratoire TransDiag | Bachelier C.,Laboratoire TransDiag | Marchandin H.,Montpellier University | And 5 more authors.
Transfusion | Year: 2014

Background Human neutrophil peptides (HNPs) 1 to 3 are the major antimicrobial peptides of the azurophilic granules of neutrophils. They represent an important arm of the innate immune system. Their production by chemical synthesis and recombinant technologies is expensive and limited by technical constraints due to their composition and the presence of three disulfide bonds. Study Design and Methods We have developed an original approach based on the purification of the natural human defensins HNPs 1 to 3 from neutrophils trapped on leukoreduction filters used in blood processing. The purification of HNPs 1 to 3 from these filters is performed in two steps: extraction of HNPs 1 to 3 retained in the filters followed by their immunoprecipitation. Studies were performed to determine the stability of defensins in the filters stored at room temperature. The activity of HNPs 1 to 3 obtained by our rapid protocol was validated by determining minimal inhibitory concentrations (MICs) against six reference bacterial strains and 12 clinical isolates. Results The human defensins HNPs 1 to 3 extracted from leukoreduction filters displayed high antimicrobial activity against tested strains, with MIC values between 0.12 and 1 μg/mL. Kinetics assays showed the appearance of activity 15 minutes after peptide addition. Moreover, we found that the HNPs 1 to 3 purified from leukoreduction filters that had been stored for 45 days at room temperature remained active. Conclusion Leukoreduction filters provide a rich and safe source of active human defensins HNPs 1 to 3. Moreover, the stability of the peptides in filters stored at room temperature allows envisaging a large-scale development of the process. © Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

Akkari L.,French National Center for Scientific Research | Akkari L.,Montpellier University | Haouzi D.,French National Center for Scientific Research | Haouzi D.,Montpellier University | And 11 more authors.
Journal of Cellular Physiology | Year: 2010

Cellular differentiation relies on both physical and chemical environmental cues. The bipotential mouse embryonic liver (BMEL) cells are early progenitors of liver epithelial cells with an apparently infinite proliferative potential. These cells, which remain undifferentiated in a monolayer culture, differentiate upon release from geometrical constraints imposed by growth on a stiff plastic plate. In a complex three dimensional environment of a Matrigel extracellular matrix, BMEL cells form two types of polarized organoids of distinct morphologies: cyst-like structures suggesting cholangiocyte-type organization or complex organoids, reminiscent of liver parenchyma and associated with acquisition of hepatocyte-specific phenotypic markers. The choice of the in vitro differentiation lineage is governed by Transforming Growth Factor-β (TGF-β) signaling. Our results suggest that morphological cues initiate the differentiation of early hepatic precursors and confirm the inhibitory role of TGF-β on hepatocytic lineage differentiation. © 2010 Wiley-Liss, Inc.

Viljoen J.,University of KwaZulu - Natal | Viljoen J.,Montpellier University | Tuaillon E.,Montpellier University | Tuaillon E.,Institute Of Recherche En Biotherapie | And 16 more authors.
AIDS | Year: 2015

Objective: Postnatal HIV-1 mother-to-child transmission (MTCT) occurs in spite of antiretroviral therapy. Co-infections in breast milk with cytomegalovirus (CMV) and Epstein-Barr virus (EBV) are associated with increased HIV-1 shedding in this compartment. We investigated CMV levels and EBV detection in breast milk as potential risk factors for MTCT of HIV-1 via breastfeeding. Methods: Cell-free HIV-1 RNA, cell-associated HIV-1 DNA, CMV and EBV DNA were quantified in breast milk from 62 HIV-infected mothers and proven postnatal MTCT of HIV-1 via breastfeeding. Controls were 62 HIV-positive mothers with HIV-uninfected infants. Results: Median (interquartile range) CMV DNA viral load was significantly higher in cases [88 044 (18 586-233 904)] than in controls [11 167 (3221-31 152)] copies/106 breast milk cells (P < 0.001). Breast milk CMV DNA level correlated positively with breast milk HIV-1 RNA level in cases and controls. EBV DNA was detectable in a higher proportion of breast milk samples of cases (37.1%) than controls (16.1%; P = 0.009). HIV-1 MTCT was strongly associated with HIV-1 RNA shedding in breast milk and plasma. In multivariable analysis, every 1 log10 increase in breast milk CMV DNA was associated with a significant 2.5-fold greater odds of MTCT of HIV-1, independent of breast milk and plasma HIV-1 levels; the nearly three-fold increased risk of HIV-1 MTCT with breast milk EBV DNA detection did not reach significance. Conclusion: We provide the first evidence of an independent association between CMV in breast milk, and postnatal MTCT of HIV-1. This association could fuel persistent shedding of HIV-1 in breast milk in women receiving antiretroviral therapy. EBV DNA detection in breast milk may also be associated with MTCT of HIV-1, but only marginally so. © 2015 Wolters Kluwer Health, Inc. All rights reserved.

Gadea G.,French National Center for Scientific Research | Gadea G.,Montpellier University | Arsic N.,French National Center for Scientific Research | Arsic N.,Montpellier University | And 25 more authors.
eLife | Year: 2016

TP53 is conventionally thought to prevent cancer formation and progression to metastasis, while mutant TP53 has transforming activities. However, in the clinic, TP53 mutation status does not accurately predict cancer progression. Here we report, based on clinical analysis corroborated with experimental data, that the p53 isoform Δ133p53β promotes cancer cell invasion, regardless of TP53 mutation status. Δ133p53β increases risk of cancer recurrence and death in breast cancer patients. Furthermore Δ133p53β is critical to define invasiveness in a panel of breast and colon cell lines, expressing WT or mutant TP53 Endogenous mutant Δ133p53β depletion prevents invasiveness without affecting mutant full-length p53 protein expression. Mechanistically WT and mutant Δ133p53β induces EMT. Our findings provide explanations to 2 long-lasting and important clinical conundrums: how WT TP53 can promote cancer cell invasion and reciprocally why mutant TP53 gene does not systematically induce cancer progression. © Gadea et al.

Kania D.,Center Muraz | Kania D.,et Maladies Associees Center Muraz | Kania D.,French Institute of Health and Medical Research | Kania D.,Montpellier University | And 19 more authors.
Clinical Microbiology and Infection | Year: 2013

People screened for human immunodeficiency virus (HIV) using rapid diagnostic tests (RDTs) in Africa remain generally unaware of their status for hepatitis B (HBV) and hepatitis C (HCV) infections. We evaluated a two-step screening strategy in Burkina Faso, using both HIV RDTs and Dried Blood Spot (DBS) assays to confirm an HIV-positive test, and to test for HBV and HCV infections. HIV counselling and point-of-care testing were performed at a voluntary counselling and testing centre with HBV, HCV status and HIV confirmation using DBS specimens, being assessed at a central laboratory. Serological testing on plasma was used as the reference standard assay to control for the performance of DBS assays. Nineteen out of 218 participants included in the study were positive for HIV using RDTs. A fourth-generation HIV ELISA and immunoblot assays on DBS confirmed HIV status. Twenty-four out of 25 participants infected with HBV were found positive for hepatitis B surface antigen (HBsAg) using DBS. One sample with a low HBsAg concentration on plasma was not detected on DBS. Five participants tested positive for HCV antibodies were confirmed positive with an immunoblot assay using DBS specimens. Laboratory results were communicated within 7 days to participants with no loss to follow up of participants between the first and second post-test counselling sessions. In conclusion, DBS collection during HIV point-of-care testing enables screening and confirmation of HBV, HCV and HIV infections. Diagnosis using DBS may assist with implementation of national programmes for HBV, HCV and HIV screening and clinical care in middle- to low-income countries. © 2013 European Society of Clinical Microbiology and Infectious Diseases.

Pangault C.,Rennes University Hospital Center | Pangault C.,University of Rennes 1 | Ame-Thomas P.,Rennes University Hospital Center | Ame-Thomas P.,University of Rennes 1 | And 17 more authors.
Leukemia | Year: 2010

Follicular lymphoma (FL) B cells contract tight connections with their microenvironment, which governs the pathogenesis and progression of the disease. Indeed, specific immune response gene signatures, obtained from whole biopsy samples, have been associated with patient survival. In this study, we performed gene expression profiling of purified B cell and non-B cell compartments obtained from FL and reactive lymph nodes. We identified 677 non-redundant genes defining the FL interface and involving 26 FL-specific functional networks. This approach highlighted an interleukin-4 (IL-4)-centered pathway associated with an activation of signal transducer and activator of transcription 6 (STAT6), which favors overexpression of IL-4-target genes. In addition, FL microenvironment was characterized by a strong enrichment in follicular helper T cells (TFH), as demonstrated through transcriptomic and flow cytometry analyses. The majority of phospho-STAT6 pos B cells were located at the vicinity of cells expressing the programmed death 1 (PD-1) TFH marker. Moreover, purified FL-derived TFH, expressed IL4 at very high levels compared with purified tonsil-derived TFH or non-T FH microenvironment. Altogether, our study demonstrated that tumor-infiltrating TFH specifically express functional IL-4 in FL, creating an IL-4-dependent TFH-B cell axis. This cross talk could sustain FL pathogenesis and represent a new potential therapeutic target. © 2010 Macmillan Publishers Limited All rights reserved.

Alix-Panabieres C.,Institute Of Recherche En Biotherapie | Alix-Panabieres C.,Montpellier University | Pierga J.-Y.,University Pierre and Marie Curie | Pierga J.-Y.,University of Paris Descartes
Bulletin du Cancer | Year: 2014

The detection and molecular characterization of circulating tumor cells (CTCs) are one of the most active areas of translational cancer research, with more than 400 clinical studies having included CTCs as a biomarker.The aims of research on CTCs include: a) estimation of the risk for metastatic relapse or metastatic progression (prognostic information); b) stratification and real-time monitoring of therapies; c) identification of therapeutic targets and resistance mechanisms; and d) understanding metastasis development in cancer patients.This review focuses on the technologies used for the enrichment and detection of CTCs. We outline and discuss the current technologies that are based on exploiting the physical and biological properties of CTCs. A number of innovative technologies to improve methods for CTC detection have recently been developed, including CTC microchips, filtration devices, quantitative reverse-transcription PCR assays, and automated microscopy systems. Molecular characterization studies have indicated, however, that CTCs are very heterogeneous, a finding that underscores the need for multiplex approaches to capture all of the relevant CTC subsets. We therefore emphasize the current challenges of increasing the yield and detection of CTCs that have undergone an epithelial-mesenchymal transition. Increasing assay analytical sensitivity may lead, however, to a decrease in analytical specificity (e.g., through the detection of circulating normal epithelial cells).A considerable number of promising CTC detection techniques have been developed in recent years. The analytical specificity and clinical utility of these methods must be demonstrated in large prospective multicenter studies to reach the high level of evidence required for their introduction into clinical practice. Copyright © 2007 John Libbey Eurotext - All rights reserved.

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