Jean-Luc Gala
Université catholique de Louvain
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Featured researches published by Jean-Luc Gala.
PLOS Medicine | 2016
Daouda Sissoko; Cédric Laouénan; Elin Folkesson; Sylvain Baize; Alseny-Modet Camara; Piet Maes; Christine Danel; Sara Carazo; Mamoudou N. Conde; Jean-Luc Gala; Géraldine Colin; Joseph Akoi; Marie-Claire Lamah; Sandra Diederich; Alexis Tounkara; Geertrui Poelart; Emmanuel Berbain; Jean-Michel Dindart; Annabelle Lefevre; Tamba Leno; Olivier Peyrouset; Romain Palich; Julia Hinzmann; Sadou Barry; Sakoba Berette; Roger Koundouno; Cécé Moriba Loua; Vincent Massala; Kinda Moumouni; Célia Provost
Background Ebola virus disease (EVD) is a highly lethal condition for which no specific treatment has proven efficacy. In September 2014, while the Ebola outbreak was at its peak, the World Health Organization released a short list of drugs suitable for EVD research. Favipiravir, an antiviral developed for the treatment of severe influenza, was one of these. In late 2014, the conditions for starting a randomized Ebola trial were not fulfilled for two reasons. One was the perception that, given the high number of patients presenting simultaneously and the very high mortality rate of the disease, it was ethically unacceptable to allocate patients from within the same family or village to receive or not receive an experimental drug, using a randomization process impossible to understand by very sick patients. The other was that, in the context of rumors and distrust of Ebola treatment centers, using a randomized design at the outset might lead even more patients to refuse to seek care. Therefore, we chose to conduct a multicenter non-randomized trial, in which all patients would receive favipiravir along with standardized care. The objectives of the trial were to test the feasibility and acceptability of an emergency trial in the context of a large Ebola outbreak, and to collect data on the safety and effectiveness of favipiravir in reducing mortality and viral load in patients with EVD. The trial was not aimed at directly informing future guidelines on Ebola treatment but at quickly gathering standardized preliminary data to optimize the design of future studies. Methods and Findings Inclusion criteria were positive Ebola virus reverse transcription PCR (RT-PCR) test, age ≥ 1 y, weight ≥ 10 kg, ability to take oral drugs, and informed consent. All participants received oral favipiravir (day 0: 6,000 mg; day 1 to day 9: 2,400 mg/d). Semi-quantitative Ebola virus RT-PCR (results expressed in “cycle threshold” [Ct]) and biochemistry tests were performed at day 0, day 2, day 4, end of symptoms, day 14, and day 30. Frozen samples were shipped to a reference biosafety level 4 laboratory for RNA viral load measurement using a quantitative reference technique (genome copies/milliliter). Outcomes were mortality, viral load evolution, and adverse events. The analysis was stratified by age and Ct value. A “target value” of mortality was defined a priori for each stratum, to guide the interpretation of interim and final analysis. Between 17 December 2014 and 8 April 2015, 126 patients were included, of whom 111 were analyzed (adults and adolescents, ≥13 y, n = 99; young children, ≤6 y, n = 12). Here we present the results obtained in the 99 adults and adolescents. Of these, 55 had a baseline Ct value ≥ 20 (Group A Ct ≥ 20), and 44 had a baseline Ct value < 20 (Group A Ct < 20). Ct values and RNA viral loads were well correlated, with Ct = 20 corresponding to RNA viral load = 7.7 log10 genome copies/ml. Mortality was 20% (95% CI 11.6%–32.4%) in Group A Ct ≥ 20 and 91% (95% CI 78.8%–91.1%) in Group A Ct < 20. Both mortality 95% CIs included the predefined target value (30% and 85%, respectively). Baseline serum creatinine was ≥110 μmol/l in 48% of patients in Group A Ct ≥ 20 (≥300 μmol/l in 14%) and in 90% of patients in Group A Ct < 20 (≥300 μmol/l in 44%). In Group A Ct ≥ 20, 17% of patients with baseline creatinine ≥110 μmol/l died, versus 97% in Group A Ct < 20. In patients who survived, the mean decrease in viral load was 0.33 log10 copies/ml per day of follow-up. RNA viral load values and mortality were not significantly different between adults starting favipiravir within <72 h of symptoms compared to others. Favipiravir was well tolerated. Conclusions In the context of an outbreak at its peak, with crowded care centers, randomizing patients to receive either standard care or standard care plus an experimental drug was not felt to be appropriate. We did a non-randomized trial. This trial reaches nuanced conclusions. On the one hand, we do not conclude on the efficacy of the drug, and our conclusions on tolerance, although encouraging, are not as firm as they could have been if we had used randomization. On the other hand, we learned about how to quickly set up and run an Ebola trial, in close relationship with the community and non-governmental organizations; we integrated research into care so that it improved care; and we generated knowledge on EVD that is useful to further research. Our data illustrate the frequency of renal dysfunction and the powerful prognostic value of low Ct values. They suggest that drug trials in EVD should systematically stratify analyses by baseline Ct value, as a surrogate of viral load. They also suggest that favipiravir monotherapy merits further study in patients with medium to high viremia, but not in those with very high viremia. Trial registration ClinicalTrials.gov NCT02329054
Clinical Pharmacology & Therapeutics | 2004
Aurel C. Allabi; Jean-Luc Gala; Yves Horsmans; Melih O. Babaoglu; Atila Bozkurt; Michel Heusterspreute; Umit Yasar
Previous data indicate that the urinary losartan/E‐3174 ratio is a marker for cytochrome P450 (CYP) 2C9 activity in vivo. The functional impact of CYP2C9*5, *6, *8, and *11 polymorphisms in vivo has not been investigated previously in humans.
Biotechnology annual review | 2002
Nathalie Zammatteo; Sandrine Hamels; Françoise de Longueville; Isabelle Alexandre; Jean-Luc Gala; Francis Brasseur; José Remacle
The DNA chips are arrays of DNA probes immobilized on solid support for simultaneous identification of many target DNA sequences. DNA chips applied to diagnosis aims to detect genomic DNA or RNA after PCR amplification. This review provides an overview of DNA chip technology, focusing on diagnostic applications. A comparison between high density and low density microarrays is given showing that low density chips are more suitable for routine applications due to their simplicity, good reproducibility, easy data management and low cost.
The Journal of Molecular Diagnostics | 2008
Bernard Vandercam; Sabine Jeumont; Olivier Cornu; Jean Cyr Yombi; Frédéric Lecouvet; Philippe Lefèvre; Léonid M. Irenge; Jean-Luc Gala
Microbiological cultures are moderately sensitive for diagnosing prosthetic joint infection (PJI). This study was conducted to determine whether amplification-based DNA methods applied on intraoperative samples could enhance PJI diagnosis compared with culture alone in routine surgical practice. Revision arthroplasty was performed for suspected PJI (n = 41) and osteoarthrosis control (n = 28) patients, and a diagnosis of PJI was confirmed in 34 patients. Amplification by polymerase chain reaction was performed on both 16S ribosomal DNA universal target genes and femA Staphylococcus-specific target genes. Species identification was achieved through amplicon sequencing. Amplification of the femA gene led to subsequent testing for methicillin resistance by amplification of the mecA gene. Microbiological and molecular assays identified a causative organism in 22 of 34 patients (64.7%) and in 31 of 34 patients (91.2%), respectively. In 18 of the 22 culture-positive patients, molecular and microbiological results were concordant for bacterial genus, species, and/or methicillin resistance. Bacterial agents were identified only by molecular methods in nine PJI patients, including seven who were receiving antibiotics at the time of surgery and one with recent but not concomitant antibiotherapy. DNA-based methods were found to effectively complement microbiological methods, without interfering with existing procedures for sample collection, for the identification of causative pathogens from intraoperative PJI samples, especially in patients with recent or concomitant antibiotherapy.
PLOS ONE | 2013
Alexandre Persu; Michel Lambert; Jaap Deinum; Marta Cossu; Nathalie de Visscher; Léonid M. Irenge; Jérôme Ambroise; Jean Marc Minon; Andrew B. Nesterovitch; Alexander Churbanov; Isolda A. Popova; Sergei M. Danilov; A.H. Jan Danser; Jean-Luc Gala
Background Angiotensin-converting enzyme (ACE) (EC 4.15.1) metabolizes many biologically active peptides and plays a key role in blood pressure regulation and vascular remodeling. Elevated ACE levels are associated with different cardiovascular and respiratory diseases. Methods and Results Two Belgian families with a 8-16-fold increase in blood ACE level were incidentally identified. A novel heterozygous splice site mutation of intron 25 - IVS25+1G>A (c.3691+1G>A) - cosegregating with elevated plasma ACE was identified in both pedigrees. Messenger RNA analysis revealed that the mutation led to the retention of intron 25 and Premature Termination Codon generation. Subjects harboring the mutation were mostly normotensive, had no left ventricular hypertrophy or cardiovascular disease. The levels of renin-angiotensin-aldosterone system components in the mutated cases and wild-type controls were similar, both at baseline and after 50 mg captopril. Compared with non-affected members, quantification of ACE surface expression and shedding using flow cytometry assay of dendritic cells derived from peripheral blood monocytes of affected members, demonstrated a 50% decrease and 3-fold increase, respectively. Together with a dramatic increase in circulating ACE levels, these findings argue in favor of deletion of transmembrane anchor, leading to direct secretion of ACE out of cells. Conclusions We describe a novel mutation of the ACE gene associated with a major familial elevation of circulating ACE, without evidence of activation of the renin-angiotensin system, target organ damage or cardiovascular complications. These data are consistent with the hypothesis that membrane-bound ACE, rather than circulating ACE, is responsible for Angiotensin II generation and its cardiovascular consequences.
Cancer Research | 2005
Nicolas Tajeddine; Jean-Luc Gala; Magali Louis; Monique Van Schoor; Bertrand Tombal; Philippe Gailly
Preferentially expressed antigen of melanoma (PRAME) is expressed in a wide variety of tumors, but in contrast with most other tumor associated antigens, it is also expressed in leukemias. The physiologic role of PRAME remains elusive. Interestingly, PRAME expression is correlated with a favorable prognosis in childhood acute leukemias. Moreover, a high expression of PRAME seems to be predominantly found in acute leukemias carrying a favorable prognosis. On these clinical observations, we assumed that PRAME could be involved in the regulation of cell death or cell cycle. In this study, we show that transient overexpression of PRAME induces a caspase-independent cell death in cultured cell lines (CHO-K1 and HeLa). Cells stably transfected with PRAME also exhibit a decreased proliferation rate due, at least partially, to an elevated basal rate of cell death. Immunocytochemistry of a FLAG-tagged PRAME, in vivo imaging of an enhanced green fluorescent protein-tagged PRAME, and Western blotting after cell fractionation reveal a nuclear localization of the protein. Using a microarray-based approach, we show that KG-1 leukemic cells stably transfected with PRAME present a significant decrease of expression of the heat-shock protein Hsp27, the cyclin-dependent kinase inhibitor p21, and the calcium-binding protein S100A4. The expression of these three proteins is known to inhibit apoptosis and has been associated with an unfavorable prognosis in a series of cancers. Finally, repression of PRAME expression by a short interfering RNA strategy increases tumorigenicity of K562 leukemic cells in nude mice. We suggest that all these observations might explain the favorable prognosis of the leukemias expressing high levels of PRAME.
Research in Microbiology | 1999
Pascal Vannuffel; Michel Heusterspreute; Michèle Bouyer; Bernard Vandercam; Marianne Philippe; Jean-Luc Gala
The femA gene encodes a protein precursor which plays a role in peptidoglycan biosynthesis in Staphylococcus aureus and is also considered as a factor influencing the level of methicillin resistance. A femA homologous gene was recently characterized in S. epidermidis, entailing the possibility of femA phylogenetic conservation in staphylococcal species. Accordingly, we assessed the presence of femA homologous genes in S. hominis and S. saprophyticus. Strategy for identification relied upon alignment of S. aureus and D. epidermidis femA sequences and upon identification of potentially conserved regions. Amplifications of portions of the femA genes were performed under permissive annealing conditions, by using several sets of primers designed to match the consensus regions. DNA sequencing of overlapping PCR fragments led to the characterization of the entire femA genes of S. hominis and S. saprophyticus, and provided more precise information on the femA start codon for all five species. The genomic organization of all these femA genes appeared highly conserved, with alternance of homologous and variable regions. On this basis, a consensus sequence of the femA gene was defined and interspecies variations were exploited to design strategies for staphylococci species-specific identification, including multiplex PCR amplification and a reverse hybridization assay.
Applied Microbiology and Biotechnology | 2012
Léonid M. Irenge; Jean-Luc Gala
Bacillus anthracis is a Gram-positive, spore-forming bacterium, which causes anthrax, an often lethal disease of animals and humans. Although the disease has been well studied since the nineteenth century, it has witnessed a renewed interest during the past decade, due to its use as a bioterrorist agent in the fall of 2001 in the USA. A number of techniques aimed at rapidly detecting B. anthracis, in environmental samples as well as in point-of-care settings for humans suspected of exposure to the pathogen, are now available. These technologies range from culture-based methods to portable DNA amplification devices. Despite recent developments, specific identification of B. anthracis still remains difficult because of its phenotypic and genotypic similarities with other Bacillus species. Accordingly, many efforts are being made to improve the specificity of B. anthracis identification. This mini-review discusses the current challenges around B. anthracis identification, not only in reach-back laboratories but also in the field (in operational conditions).
Annals of Hematology | 1994
Jean-Luc Gala; Christiane Vermylen; Guy Cornu; Augustin Ferrant; Jean-Louis Michaux; Marianne Philippe; Philippe Martiat
SummaryBcl-2 expression and its prognostic value were evaluated using the APAAP technique in 40 ALL patients. Because of a possible synergy between c-myc and bcl-2 proteins in cell lines, we compared 40 ALL of either T or B lineage with seven Burkitts ALL or sporadic Burkitts lymphomas (BL). We found the same high expression of bcl-2 in adult (Ad) and childhood (Ch) malignancies examined at presentation, regardless of the T or B phenotype. No bcl-2 expression was detectable in BL cases, except for two investigated at relapse. Bcl-2 staining intensity was also not related to the stage of blast differentiation, except in Ad T-ALL, or to the relapse rate. Ki-67, a marker of proliferation, was used to investigate the possible correlation between bcl-2 expression and the proliferative activity. An inverse correlation was found only in BL at presentation. We confirm that bcl-2 expression is the rule in ALL, regardless of the immunophenotypic characteristics at presentation, and that high expression is not correlated with a bad prognosis. Sporadic BL may represent a particular type of tumor, with bcl-2 expression in relapse, but not at presentation.
British Journal of Cancer | 2009
Pascal Eschwège; Stéphane Moutereau; Stéphane Droupy; Richard Douard; Jean-Luc Gala; G. Benoit; Marc Conti; Philippe Manivet; S Loric
In clinically organ-confined prostate cancer patients, bloodstream tumour cell dissemination generally occurs, and may be enhanced by surgical prostate manipulation. To evaluate cancer-cell seeding impact upon patient recurrence-free survival, 155 patients were prospectively enrolled then followed. Here, 57 patients presented blood prostate cell shedding preoperatively and intraoperatively (group I). Of the 98 preoperatively negative patients, 53 (54%) remained negative (group II) and 45 (46%) became intraoperatively positive (group III). Median biological and clinical recurrence-free time was far shorter in group I (36.2 months, P<0.0001) than in group II (69.6 months) but did not significantly differ in group II and III (69.6 months vs 65.0). Such 5-year follow-up data show that preoperative circulating prostate cells are an independent prognosis factor of recurrence. Moreover, tumour handling induces cancer-cell seeding but surgical blood dissemination does not accelerate cancer evolution.