Exposure of Mycobacteriodes abscessus clones to mucin affects bacterial phenotype.

In the past 20 years infections caused by Mycobacterioides abscessus have become increasingly common in patients with chronic lung conditions. The microorganisms are also resistant to a number of antibiotic classes, making treatment challenging. To begin understanding how the bacterium adapts to the lung environment, pure colonies of M.

ability to interact with the host mucosal cells plays an important role in pathogenesis of the infection.

Non-tuberculous mycobacteria (NTM) are opportunistic pathogens ubiquitous in the environment. is a relatively new pathogen associated with underlying lung chronic pathologies, accounting for most of the pulmonary infections linked to the rapidly growing mycobacteria group. This includes chronic obstructive pulmonary disease, bronchiectasis, or cystic fibrosis.

Triple-Antibiotic Combination Exerts Effective Activity against subsp. Biofilm and Airway Infection in an In Vivo Murine Model.

Objectives: Slow-growing nontuberculous mycobacteria (NTMs) are highly prevalent and routinely cause opportunistic intracellular infectious disease in immunocompromised hosts.

Methods: The activity of the triple combination of antibiotics, clarithromycin (CLR), rifabutin (RFB), and clofazimine (CFZ), was evaluated and compared with the activity of single antibiotics as well as with double combinations in an in vitro biofilm assay and an in vivo murine model of subsp. () lung infection.

Immunological and microbial shifts in the aging rhesus macaque lung during nontuberculous mycobacterial infection.

Unlabelled: Nontuberculous mycobacteria (NTM) are environmentally ubiquitous organisms that predominately cause NTM pulmonary disease (NTMPD) in individuals over the age of 65. The incidence of NTMPD has increased in the U.S.

Fatty Acyl-CoA Synthetase D33 Promotes Survival in Hostile Extracellular and Intracellular Microenvironments in the Host.

Tuberculosis, caused by (), remains a significant global health challenge. The survival of in hostile extracellular and intracellular microenvironments is crucial for its pathogenicity. In this study, we discovered a (BCG) mutant B1033 that potentially affected mycobacterium pathogenicity.

Metabolic pathways that permit subsp. to transition to different environments encountered within the host during infection.

Introduction: is an intracellular, facultative bacterium known to colonize and infect the human host through ingestion or respiratory inhalation. The majority of pulmonary infections occur in association with pre- existing lung diseases, such as bronchiectasis, cystic fibrosis, or chronic obstructive pulmonary disease. is also acquired by the gastrointestinal route in immunocompromised individuals such as human immunodeficiency virus HIV-1 patients leading to disseminated disease.

Professional Student Education and Training During the COVID-19 Pandemic.

Introduction: The ongoing COVID-19 pandemic has presented numerous challenges to education at all levels, but has been particularly challenging for professional schools and other educational sectors that require intensive hands-on training. Those institutions have had to deploy and continuously adapt new learning strategies in response to an ever-changing pandemic landscape over the past two years, while at the same time meeting the rigorous proficiency standards for their students.

Methods: This communication describes how two professional schools at Oregon State University, the College of Pharmacy and the Carlson College of Veterinary Medicine, pivoted in response to the COVID-19 pandemic to ensure continuity in student training.

Induction of killing of Mycobacterium avium subsp. hominissuis in macrophages by cytokine stimulated innate-like lymphoid cells is negatively affected by the pathogen.

Mycobacterium avium subsp. hominissuis (MAH) is a common environmental bacterium that causes infection in immunocompromised patients such as those with HIV/AIDS, or patients with chronic lung disease such as cystic fibrosis. There are many strains of MAH with varying levels of virulence.

Mycobacterium abscessus infection results in decrease of oxidative metabolism of lung airways cells and relaxation of the epithelial mucosal tight junctions.

Mycobacterium abscessus complex is a group of environmental pathogens that recently have been isolated more from patients with underlying lung diseases, such and COPD, bronchiectasis, and cystic fibrosis. The mechanisms involved in the pathogenesis of these diseases have only recently been investigated. Infection is associated with biofilm formation on the airway mucosa, invasion of the mucosal epithelial cells and a time-dependent impairment of the integrity of the monolayer.

Functional, transcriptional, and microbial shifts associated with healthy pulmonary aging in rhesus macaques.

Older individuals are at increased risk of developing severe respiratory infections. However, our understanding of the impact of aging on the respiratory tract remains limited as samples from healthy humans are challenging to obtain and results can be confounded by variables such as smoking and diet. Here, we carry out a comprehensive cross-sectional study (n = 34 adult, n = 49 aged) to define the consequences of aging on the lung using the rhesus macaque model.

Virulent subspecies subverts macrophages during early stages of infection.

Virulent non-tuberculous Mycobacteria (NTMs) successfully reside and multiply within the phagosomes of phagocytic cells such as monocytes and macrophages. Macrophages play a very important role in the innate clearance of intracellular pathogens including NTMs. Attenuated subsp.

Environment in the lung of cystic fibrosis patients stimulates the expression of biofilm phenotype in .

Pulmonary infections caused by organisms of the complex are increasingly prevalent in populations at risk, such as patients with cystic fibrosis, bronchiectasis and emphysema. infection of the lung is not observed in immunocompetent individuals, which raises the possibility that the compromised lung environment is a suitable niche for the pathogen to thrive in due to the overproduction of mucus and high amounts of host cell lysis. Evaluate the ability of to form biofilm and grow utilizing conditions as seen in immunocompromised lungs of patients.

Subsp. Interactions with Macrophage Killing Mechanisms.

Non-tuberculosis mycobacteria (NTM) are ubiquitously found throughout the environment. NTM can cause respiratory infections in individuals with underlying lung conditions when inhaled, or systemic infections when ingested by patients with impaired immune systems. Current therapies can be ineffective at treating NTM respiratory infections, even after a long course or with multidrug treatment regimens.

Small RNA Profiling in Provides Insights Into Stress Adaptability.

encounter a number of environmental changes during infection and respond using different mechanisms. Small RNA (sRNA) is a post-transcriptionally regulatory system for gene functions and has been investigated in many other bacteria. This study used and Bacillus Calmette-Guérin (BCG) infection models and sequenced whole bacterial RNAs before and after host cell infection.

An Analysis of the Infections and Determination of Empiric Antibiotic Therapy in Cats and Dogs with Cancer-Associated Infections.

Cancer patients commonly develop infectious complications over the course of the disease. One thousand patients receiving treatment for an oncologic disease at a single veterinary teaching hospital were retrospectively reviewed for concurrent infections. A total of 153 confirmed bacterial infections were identified, 82 of which were abscesses or wounds, 13 of which were respiratory infections, 3 of which were ear infections, and 55 of which were urinary tract infections.

Mycobacterium avium subsp. hominissuis (MAH) Microaggregate induction of host innate immunity is linked to biofilm formation.

Bacterial aggregation is a strategy employed by many pathogens to establish infection. Mycobacterium avium subsp. hominissuis (MAH) undergoes a phenotypic change, microaggregation, when exposed to the respiratory epithelium.

Macrophage Proteome Analysis at Different Stages of Subspecies Infection Reveals a Mechanism of Pathogen Dissemination.

Johne's disease is a chronic and usually fatal enteric infection of ruminants caused by subspecies (MAP) and is responsible for hundreds of millions of dollars in losses for the agricultural industry. Natural infection typically begins with bacterial uptake and translocation through the epithelium of the small intestine, followed by ingestion by tissue macrophages and dissemination via the lymphatic or blood system throughout the body. To gain insights into the host responses and adaptation of MAP within phagocytic cells, we utilized the previously developed cell culture passage model, and mass spectrometric-based quantitative proteomic approach.

Exposure of subsp. to Metal Concentrations of the Phagosome Environment Enhances the Selection of Persistent Subpopulation to Antibiotic Treatment.

subspecies (MAH) is an opportunistic intracellular pathogen causing infections in individuals with chronic lung conditions and patients with immune-deficient disorders. The treatment of MAH infections is prolonged and outcomes many times are suboptimal. The reason for the extended treatment is complex and reflects the inability of current antimicrobials to clear diverse phenotypes of MAH quickly, particularly, the subpopulation of susceptible but drug-tolerant bacilli where the persistent fitness to anti-MAH drugs is stimulated and enhanced by the host environmental stresses.

as a Screening Tool for Subspecies Virulence Factors with Relevance in Macrophage Infection.

The high prevalence of Johne's disease has driven a continuous effort to more readily understand the pathogenesis of the etiological causative bacterium, subsp. (MAP), and to develop effective preventative measures for infection spread. In this study, we aimed to create an in vivo MAP infection model employing an environmental protozoan host and used it as a tool for selection of bacterial virulence determinants potentially contributing to MAP survival in mammalian host macrophages.

Short-Chain Fatty Acids Promote subsp. Growth in Nutrient-Limited Environments and Influence Susceptibility to Antibiotics.

subsp. (MAH) is a common intracellular pathogen that infects immunocompromised individuals and patients with pre-existing chronic lung diseases, such as cystic fibrosis, who develop chronic and persistent pulmonary infections. The metabolic remodeling of MAH in response to host environmental stresses or within biofilms formed in bronchial airways plays an important role in development of the persistence phenotype contributing to the pathogen's tolerance to antibiotic treatment.

Investigating the Role of Mucin as Frontline Defense of Mucosal Surfaces against Subsp. .

is a human and animal pathogen that infects the host through the mucosal surfaces. Past work has demonstrated that the bacterium can interact with both the respiratory and gastrointestinal tracts. Those surfaces in the body are covered by a bilayer of a glycoprotein, mucin, which works as a physical barrier and a gel which contains antibacterial and antivirus properties.

Polysaccharide Succinylation Enhances the Intracellular Survival of .

Lipoarabinomannan (LAM) and its biosynthetic precursors, phosphatidylinositol mannosides (PIMs) and lipomannan (LM) play important roles in the interactions of with phagocytic cells and the modulation of the host immune response, but nothing is currently known of the impact of these cell envelope glycoconjugates on the physiology and pathogenicity of nontuberculous mycobacteria. We here report on the structures of PIM, LM, and LAM. Intriguingly, these structures differ from those reported previously in other mycobacterial species in several respects, including the presence of a methyl substituent on one of the mannosyl residues of PIMs as well as the PIM anchor of LM and LAM, the size and branching pattern of the mannan backbone of LM and LAM, and the modification of the arabinan domain of LAM with both succinyl and acetyl substituents.