To examine the macrophage response to M. avium, I compared inflammasome and cytosolic sensor expression and activation. My result demonstrated that virulent strains of M. avium (A5 and 104) suppress IL-1β production and induce IFN-β production in macrophages. M. avium mutants deficient at DNA export in the biofilm exhibited reduced...
Interference with the host post-translational mechanisms, such as protein phosphorylation, is a key strategy used by many intracellular bacterial pathogens to subvert host immune cell function. Virulent non-tuberculous Mycobacteria (NTMs) unlike attenuated or non-pathogenic NTMs, successfully reside and multiply within the phagosomes of phagocytic cells such as monocytes and macrophages....
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. This aggregation is an important step in the pathogenesis of the infection, laying the foundation for biofilm formation. We therefore compared how...
Mycobacterium avium subspecies hominissuis (MAH) is an opportunistic pathogen that is ubiquitous in the environment and often isolated from faucets and showerheads. MAH mostly infects humans with an underlying disease, such as chronic pulmonary disorder (COPD), cystic fibrosis (CF), or are immunocompromised, though infections in patients without concurrent disease are...
Mycobacterium avium subspecies hominissuis (MAH) is the most common pathogen among non-tuberculous mycobacteria, causing disease in immunocompromised individuals. An intracellular bacterium, MAH resides within the phagosome, a vesicle formed by macrophages as they engulf invading pathogens. Here, a subpopulation of MAH regresses into a nonreplicative state called persistence, allowing them...
Respiratory infections caused by nontuberculous mycobacteria (NTM), especially Mycobacterium avium, can lead to progressive, recurrent disease that is refractory to therapy. Bacterial biofilms are intrinsically resistant to a variety of stressors and pressures, including host killing mechanisms and antibiotic therapy. Though it is becoming increasingly evident that NTM biofilms are...
Cases of pulmonary diseases caused by Mycobacterium avium complex (MAC) have increased over the years and have become a major health concern in Europe, Asia, and the United States. MAC, comprised of M. avium species and M. intracellulare, are found everywhere in the environment: in water sources and the soil....
Mycobacterium avium subspecies hominissuis (MAH) causes potentially lethal opportunistic infections in immunocompromised individuals. Lack of a good animal model system currently hinders in vivo study of MAH virulence. Here we applied the tractable organism Caenorhabditis elegans (C. elegans), as a surrogate host to study the virulence of MAH. Worms were...
Mycobacterium avium subsp hominissuis (MAH) is an opportunistic environmental pathogen that causes respiratory and gastrointestinal illness in immunocompromised persons such as those with chronic respiratory diseases or AIDs, respectively. In recent years, there has been a significant increase in the incidence of nontuberculous mycobacterial (NTM) lung infections, including in cystic...
Mycobacterium avium subspecies paratuberculosis (MAP) is the causative agent of Johne's disease, a chronic inflammatory bowel disease that affects ruminant populations worldwide. The characteristic stages of the disease make diagnosis difficult, resulting in silent transmission among animals in a herd for years before proper detection of the infection. The extensive...