Search results for "Mycobacterium bovis"
showing 10 items of 17 documents
Rapid dissemination of Mycobacterium bovis from cattle dung to soil by the earthworm Lumbricus terrestris
2016
International audience; Indirect transmission of Mycobacterium bovis, the causative agent of bovine tuberculosis (bTB), between wildlife and livestock is thought to occur by inhalation or ingestion of environmental substrates contaminated through animal shedding. The role of the soil fauna, such as earthworms, in the circulation of M. bovis from contaminated animal feces is of interest in the epidemiology of bTB. The objective of this study was to assess the impact of earthworm activity on M. bovis transfer from animal dung to castings and the surrounding soil. For this purpose, microcosms of soil containing the anecic eathworms Lumbricus terrestris were prepared and covered with cattle fec…
First molecular detection of mycobacterium bovis in environmental samples from a French region with endemic bovine tuberculosis
2016
Aims The aim of the study was to determine the prevalence of Mycobacterium bovis (the causative agent of bovine tuberculosis, bTB) in environmental matrices within a French region (Cote d'Or) affected by this zoonotic disease. Methods and Results We report here the development and the use of molecular detection assays based on qPCR (double fluorescent dye labelled probe) to monitor the occurrence of Mycobacterium tuberculosis complex (MTBC) or M. bovis in environmental samples collected in pastures where infected cattle and wildlife had been reported. Three qPCR assays targeting members of the MTBC (IS1561’ and Rv3866 loci) or M. bovis (RD4 locus) were developed or refined from existing ass…
Impact of temperature and soil type on Mycobacterium bovis survival in the environment
2017
Mycobacterium bovis, the causative agent of the bovine tuberculosis (bTB), mainly affects cattle, its natural reservoir, but also a wide range of domestic and wild mammals. Besides direct transmission via contaminated aerosols, indirect transmission of the M. bovis between wildlife and livestock might occur by inhalation or ingestion of environmental substrates contaminated through infected animal shedding. We monitored the survival of M. bovis in two soil samples chosen for their contrasted physical and-chemical properties (i.e. pH, clay content). The population of M. bovis spiked in sterile soils was enumerated by a culture-based method after 14, 30, 60, 90, 120 and 150 days of incubation…
Characterization of lung γδ T cells following intranasal infection with Mycobacterium bovis bacillus Calmette-Guérin
2002
The lungs are considered to have an impaired capacity to contain infection by pathogenic mycobacteria, even in the presence of effective systemic immunity. In an attempt to understand the underlying cellular mechanisms, we characterized the gammadelta T cell population following intranasal infection with Mycobacterium bovis bacillus Calmette-Guerin (BCG). The peak of gammadelta T cell expansion at 7 days postinfection preceded the 30 day peak of alphabeta T cell expansion and bacterial count. The expanded population of gammadelta T cells in the lungs of BCG-infected mice represents an expansion of the resident Vgamma2 T cell subset as well as an influx of Vgamma1 and of four different Vdelt…
An anti-inflammatory role for V alpha 14 NK T cells in Mycobacterium bovis bacillus Calmette-Guérin-infected mice.
2003
Abstract The possible contribution of NKT cells to resistance to Mycobacterium tuberculosis infection remains unclear. In this paper we characterized the Vα14 NKT cell population following infection with Mycobacterium bovis bacillus Calmette-Guérin (BCG). BCG infection determined an early expansion of Vα14 NKT cells in liver, lungs, and spleen, which peaked on day 8 and was sustained until day 30. However, an NK1.1+ Vα14 NKT population preferentially producing IFN-γ predominated at an early stage (day 8), which was substituted by an NK1.1− population preferentially producing IL-4 at later stages (day 30). Despite the fact that Vα14 NKT cell-deficient mice eliminated BCG as did control mice…
Molecular epidemiology and whole genome sequencing analysis of clinical Mycobacterium bovis from Ghana
2019
[Background]: Bovine tuberculosis (bTB) caused by Mycobacterium bovis is a re-emerging problem in both livestock and humans. The association of some M. bovis strains with hyper-virulence, MDR-TB and disseminated disease makes it imperative to understand the biology of the pathogen.
The Factors Affecting Expansion of Reactive Tumor Infiltrating Lymphocytes (TIL) From Bladder Cancer and Potential Therapeutic Applications
2021
Tumor infiltrating lymphocytes (TIL) therapy was shown to provide durable objective response in patients with metastatic melanoma. As a fundamental first step to bring TIL therapy to clinical use, identification of patients whose tumors yield optimal numbers of reactive TIL is indispensable. We have previously shown that expansion of tumor reactive TIL from primary bladder tumors and lymph node metastases is feasible. Here, we performed TIL harvesting from additional surgical specimens (additional 31 primary tumors and 10 lymph nodes) to generate a heterogenous cohort of 53 patients with bladder cancer (BC) to evaluate the tumor characteristics that lead to tumor-reactive TIL expansion. Amo…
Snapshot of Moving and Expanding Clones of Mycobacterium tuberculosis and Their Global Distribution Assessed by Spoligotyping in an International Stu…
2003
ABSTRACT The present update on the global distribution of Mycobacterium tuberculosis complex spoligotypes provides both the octal and binary descriptions of the spoligotypes for M. tuberculosis complex, including Mycobacterium bovis , from >90 countries (13,008 patterns grouped into 813 shared types containing 11,708 isolates and 1,300 orphan patterns). A number of potential indices were developed to summarize the information on the biogeographical specificity of a given shared type, as well as its geographical spreading (matching code and spreading index, respectively). To facilitate the analysis of hundreds of spoligotypes each made up of a binary succession of 43 bits of information, …
Global Distribution and Evolution of Mycobacterium bovis Lineages
2020
Mycobacterium bovis is the main causative agent of zoonotic tuberculosis in humans and frequently devastates livestock and wildlife worldwide. Previous studies suggested the existence of genetic groups of M. bovis strains based on limited DNA markers (a.k.a. clonal complexes), and the evolution and ecology of this pathogen has been only marginally explored at the global level. We have screened over 2,600 publicly available M. bovis genomes and newly sequenced four wildlife M. bovis strains, gathering 1,969 genomes from 23 countries and at least 24 host species, including humans, to complete a phylogenomic analyses. We propose the existence of four distinct global lineages of M. bovis (Lb1, …
Although rare, severe complications following intravesical bacillus Calmette-Guerin treatment should not be overlooked!
2015
An interesting series of 22 patients affected by severe systemic toxicity following bacillus Calmette-Guerin (BCG) intravesical adjuvant therapy for bladder cancer is presented in this issue of Inf...