A5002733435- Tuberculosis Research and Epidemiology
- Mycobacterium research and diagnosis
- Immune responses and vaccinations
- Immunodeficiency and Autoimmune Disorders
- Neutrophil, Myeloperoxidase and Oxidative Mechanisms
- Immune Response and Inflammation
- Leprosy Research and Treatment
- Immune cells in cancer
- T-cell and B-cell Immunology
- Immunotherapy and Immune Responses
- Immune Cell Function and Interaction
- Diagnosis and treatment of tuberculosis
- HIV Research and Treatment
- Neonatal Respiratory Health Research
- Pharmacological Effects of Natural Compounds
- Virus-based gene therapy research
- Bacteriophages and microbial interactions
- Inflammasome and immune disorders
- Infectious Diseases and Tuberculosis
- Cystic Fibrosis Research Advances
- Cell Adhesion Molecules Research
- Zoonotic diseases and public health
- vaccines and immunoinformatics approaches
- Infectious Diseases and Mycology
- Milk Quality and Mastitis in Dairy Cows
Université de Tours
2012-2024
Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement
2019-2024
Biologie des Oiseaux et Aviculture
2024
Infectiologie Animale et Santé Publique
2014-2023
Centre Val de Loire
2010-2017
Institut National de la Recherche Agronomique
2015
Institut Pasteur
2001-2010
Molina Center for Energy and the Environment
2008
Génétique Moléculaire Génomique Microbiologie
1995-2008
Erasmus MC
2005
Two-component regulatory signal transduction systems are important elements of the adaptative response prokaryotes to a variety environmental stimuli. Disruption PhoP-PhoR in Mycobacterium tuberculosis dramatically attenuates virulence, implying that this system directly and/or indirectly coordinates expression virulence factors whose identity remains be established. Interestingly, knockingout two-component M. Mt103, dramatic changes colonial morphology, cording properties, and reactivity...
Abstract In the present study, we investigated in vivo infection and APC functions of dendritic cells (DC) macrophages (Mφ) after administration live mycobacteria to mice. Experiments were conducted with Mycobacterium bovis bacillus Calmette-Guerin (BCG) or a rBCG expressing reporter Ag. Following mice, DC Mφ purified presence immunogenic peptide/MHC class II complexes was detected ex on sorted cells, as secretion IL-12 p40. We show this study that is host cell for mycobacteria, provide an...
The growth of Mycobacterium tuberculosis mutants unable to synthesize phthiocerol dimycocerosates (DIMs) was recently shown be impaired in mouse lungs. However, the precise role these molecules course infection remained determined. Here, we provide evidence that attenuation a DIM-deficient strain takes place during acute phase both lungs and spleen mice, this results part from increased sensitivity mutant cidal activity reactive nitrogen intermediates released by activated macrophages. We...
Leptospirosis is a widespread zoonosis caused by pathogenic Leptospira interrogans that are transmitted asymptomatic infected rodents. Leptospiral lipoproteins and LPS have been shown to stimulate murine cells via TLRs 2 4. Host defense mechanisms remain obscure, although TLR4 has be involved in clearing Leptospira. In this study, we show double (TLR2 TLR4) knockout (DKO) mice rapidly died from severe hepatic renal failure following inoculation. Strikingly, the proinflammatory response...
Mycolactone is a polyketide toxin produced by Mycobacterium ulcerans (Mu), the causative agent of skin disease Buruli ulcer (BU). Surprisingly, infected tissues lack inflammatory infiltrates. Structural similarities between mycolactone and immunosuppressive agents led us to investigate immunomodulatory properties on dendritic cells (DCs), key initiators regulators immune responses. At noncytotoxic concentrations, phenotypic functional maturation both mouse human DCs was inhibited...
During chronic infection with Mycobacterium tuberculosis (Mtb), bacilli multiplication is constrained within lung granulomas until excessive inflammation destroys the lung. Neutrophils are recruited early and participate in granuloma formation, but neutrophilia exacerbates disease. thus appear as potential targets for therapeutic interventions, especially patients whom no antibiotic treatment possible. Signals that regulate neutrophil recruitment to during mycobacterial need be better...
The Mycobacterium tuberculosis complex (MTBC) is the collective term given to group of bacteria that cause (TB) in mammals. It has been reported M. H37Rv, a standard reference MTBC strain, attenuated cattle compared bovis. However, as H37Rv was isolated early 1930s, and genetic variants are known exist, we sought revisit this question attenuation for by performing bovine experimental infection with recent isolate. Here report using bovis AF2122/97, BTB1558, latter 2008 during TB surveillance...
Multiple regulated neutrophil cell death programs contribute to host defense against infections. However, despite expressing all necessary inflammasome components, neutrophils are thought be generally defective in Caspase-1-dependent pyroptosis. By screening different bacterial species, we found that several Pseudomonas aeruginosa ( P . ) strains trigger pyroptosis human and murine neutrophils. Notably, deletion of Exotoxins U or S enhanced pyroptosis, suggesting these exotoxins interfere...
Langerin is a C-type lectin expressed by subset of dendritic leukocytes, the Langerhans cells (LC).Langerin cell surface receptor that induces formation an LC-specific organelle, Birbeck granule (BG).We generated langerin ؊/؊ mouse on C57BL/6 background which did not display any macroscopic aberrant development.In absence langerin, LC were detected in normal numbers epidermis but lacked BG.LC mice present other phenotypic alterations compared to wild-type littermates.Functionally, able...
Abstract Neutrophils are increasingly thought to modulate dendritic cell (DC) functions. We investigated the role of neutrophil‐DC partnership in response Mycobacterium bovis BCG–the vaccine used against tuberculosis. compared crosstalk humans and mice, searching for functional differences. In both species, neutrophils captured fluorescent BCG‐enhanced green protein (EGFP) were more phagocytic than DC. Non‐apoptotic BCG‐infected clustered with immature DC, establishing intimate contacts...
Abstract Early immune response to the largely used Mycobacterium bovis bacillus Calmette-Guérin (BCG) intradermal vaccine remains ill defined. Three days after BCG inoculation into mouse ear, in addition neutrophils infiltrating skin, we observed CD11b+Ly-6CintLy-6G− myeloid cells. Neutrophil depletion markedly enhanced their recruitment. These cells differed from inflammatory monocytes and required MyD88-dependent BCG-specific signals invade whereas neutrophil influx was MyD88 independent....
The recent development of acellular pertussis vaccines has been a significant improvement in the conventional whole-cell diphtheria-pertussis-tetanus toxoid vaccines, but high production costs will limit its widespread use developing countries. Since Mycobacterium bovis BCG vaccination against tuberculosis is used most countries, recombinant BCG-pertussis vaccine could be more viable alternative. We have constructed (rBCG) strains expressing genetically detoxified S1 subunit toxin 9K/129G...
Linear plasmids were unknown in mycobacteria until recently. Here, we report the complete nucleotide sequence of 23-kb linear plasmid pCLP from Mycobacterium celatum, an opportunistic pathogen. The revealed at least 19 putative open reading frames (ORFs). Expression genes exponential-phase cultures was determined by reverse transcriptase PCR (RT-PCR). Twelve ORFs expressed, whereas no transcription 7 other detected. Five 12 transcribed detected RT-PCR are function. Sequence analysis similar...
In their mammalian hosts, Leishmania are obligate intracellular parasites that mainly reside in macrophages. They also phagocytosed by dendritic cells (DCs), which play decisive roles the induction and shaping of T cell-dependent immune responses. Little is known about role DCs life cycle. Here, we examined ability mouse bone marrow-derived to serve as hosts for L. amazonensis. Both infective stages (metacyclic promastigotes amastigotes) could be DCs, regardless whether they had previously...
Summary A promoter sequence, P an' , was isolated from Mycobacterium paratuberculosis and characterized. This lies adjacent to, outside, the 3’end of an IS 900 insertion element. contains open reading frame, ORF2, on complementary strand which codes for putative transposase this sequence. DNA fragment containing AN part ORF2 fused to lacZ gene inserted into replicative shuttle vector pRR3. smegmatis bovis BCG (BCG) transformed with plasmid exhibited β‐galactosidase activity. However, only...
ABSTRACT Bivalent recombinant strains of Mycobacterium bovis BCG (rBCG) expressing the early regulatory nef and structural gag (p26) genes from simian immunodeficiency virus (SIV) SIVmac251 were engineered so that both cotranscribed a synthetic operon. The expression cassette was cloned into multicopy-replicating vector, levels in bivalent rBCG( nef-gag ) strain found to be comparable those monovalent or strains. However, extrachromosomal cloning operon replicative plasmid resulted low...
Abstract Neutrophils participate in the control of mycobacterial infection both by directly eliminating bacilli and interacting with macrophages dendritic cells (DCs). Despite host defenses, slow-growing mycobacteria can persist for decades, mostly inside DCs, eventually destroy tissues after exacerbated inflammation. IL-17A–driven neutrophil recruitment may this process. We report that mouse bone marrow–derived DCs infected live Mycobacterium bovis Bacillus Calmette-Guérin (BCG) produced...
Nanoenabled drug delivery systems against tuberculosis (TB) are thought to control pathogen replication by targeting antibiotics infected tissues and phagocytes. However, whether nanoparticle (NP)-based carriers directly interact with Mycobacterium how such induce intracellular bacterial killing macrophages is not defined. In the present study, we demonstrated that a highly hydrophobic citral-derived isoniazid analogue, termed JVA, significantly increases nanoencapsulation inhibits M. growth...
Abstract The cytokine IL-17A has been shown to play critical roles in host defense against bacterial and fungal infections at different epithelial sites, but its role the of mammary gland (MG) seldom investigated, although MG constitute main pathology afflicting dairy cows. In this study, we showed that contributes Escherichia coli infection by using a mouse mastitis model. After inoculation with mastitis-causing E. strain, load increased rapidly, triggering an intense influx leukocytes into...