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Scientific Reports Jun 2024Mycobacterium avium subspecies paratuberculosis (MAP) is the causative agent of Johne's Disease, a chronic granulomatous enteritis of ruminants. MAP establishes an...
Mycobacterium avium subspecies paratuberculosis (MAP) is the causative agent of Johne's Disease, a chronic granulomatous enteritis of ruminants. MAP establishes an infection in the host via the small intestine. This requires the bacterium to adhere to, and be internalised by, cells of the intestinal tract. The effector molecules expressed by MAP for this purpose remain to be fully identified and understood. Mammalian cell entry (mce) proteins have been shown to enable other Mycobacterial species to attach to and invade host epithelial cells. Here, we have expressed Mce1A, Mce1D, Mce3C and Mce4A proteins derived from MAP on the surface of a non-invasive Escherichia coli to characterise their role in the initial interaction between MAP and the host. To this end, expression of mce1A was found to significantly increase the ability of the E. coli to attach and survive intracellularly in human monocyte-like THP-1 cells, whereas expression of mce1D was found to significantly increase attachment and invasion of E. coli to bovine epithelial cell-like MDBK cells, implying cell-type specificity. Furthermore, expression of Mce1A and Mce1D on the surface of a previously non-invasive E. coli enhanced the ability of the bacterium to infect 3D bovine basal-out enteroids. Together, our data contributes to our understanding of the effector molecules utilised by MAP in the initial interaction with the host, and may provide potential targets for therapeutic intervention.
Topics: Mycobacterium avium subsp. paratuberculosis; Paratuberculosis; Animals; Humans; Cattle; Bacterial Proteins; Bacterial Adhesion; Epithelial Cells; Escherichia coli; Cell Line; THP-1 Cells
PubMed: 38942800
DOI: 10.1038/s41598-024-65592-2 -
Annals of Agricultural and... Jun 2024. Pets infected with zoonotic pathogens might become a source of infections for their owners, especially those who are immuno-compromised. The aim of this report is to...
. Pets infected with zoonotic pathogens might become a source of infections for their owners, especially those who are immuno-compromised. The aim of this report is to describe a case of chronic, untreatable pneumonia in a domestic ferret. The subject was a 5-year-old female ferret suffering from recurrent pneumonia. Ante-mortally, swabs from the nasal cavity, alveolus and throat were collected from the animal. Post-mortally, lesioned organ fragments were collected. Standard microbiological testing was performed. Additionally, mycobacterial diagnosis including culture and molecular tests was performed. . The co-infection of Mycobacterium avium and Klebsiella pneumoniae was microbiologically confirmed. This case demonstrates the need to pay attention to the possibility of zoonotic pathogens in ferrets. Veterinarians diagnosing ferrets are potentially exposed to Mycobacteria spp. infections and other pathogens.
Topics: Animals; Ferrets; Female; Klebsiella pneumoniae; Coinfection; Klebsiella Infections; Mycobacterium avium; Tuberculosis; Fatal Outcome
PubMed: 38940116
DOI: 10.26444/aaem/174216 -
Antibiotics (Basel, Switzerland) May 2024Slow-growing nontuberculous mycobacteria (NTMs) are highly prevalent and routinely cause opportunistic intracellular infectious disease in immunocompromised hosts.
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.
RESULTS
Treatment of 1-week-old biofilms with the triple combination exerted the strongest effect of all (0.12 ± 0.5 × 10 CFU/mL) in reducing bacterial growth as compared to the untreated (5.20 ± 0.5 × 10/mL) or any other combination (≥0.75 ± 0.6 × 10/mL) by 7 days. The treatment of mice intranasally infected with with either CLR and CFZ or the triple combination provided the greatest reduction in CLR-sensitive bacterial counts in both the lung and spleen compared to any single antibiotic or remaining double combination by 4 weeks posttreatment. After 4 weeks of treatment with the triple combination, there were no resistant colonies detected in mice infected with a CLR-resistant strain. No clear relationships between treatment and spleen or lung organ weights were apparent after triple combination treatment.
CONCLUSIONS
The biofilm assay data and mouse disease model efficacy results support the further investigation of the triple-antibiotic combination.
PubMed: 38927142
DOI: 10.3390/antibiotics13060475 -
Archiv Der Pharmazie Jun 2024Nontuberculous mycobacteria (NTM), which include the Mycobacterium avium complex, are classified as difficult-to-treat pathogens due to their ability to quickly develop...
Nontuberculous mycobacteria (NTM), which include the Mycobacterium avium complex, are classified as difficult-to-treat pathogens due to their ability to quickly develop drug resistance against the most common antibiotics used to treat NTM infections. The overexpression of efflux pumps (EPs) was demonstrated to be a key mechanism of clarithromycin (CLA) resistance in NTM. Therefore, in this work, 24 compounds from an in-house library, characterized by chemical diversity, were tested as potential NTM EP inhibitors (EPIs) against Mycobacterium smegmatis mc155 and M. avium clinical isolates. Based on the acquired results, 12 novel analogs of the best derivatives 1b and 7b were designed and synthesized to improve the NTM EP inhibition activity. Among the second set of compounds, 13b emerged as the most potent NTM EPI. At a concentration of 4 µg/mL, it reduced the CLA minimum inhibitory concentration by 16-fold against the clinical isolate M. avium 2373 overexpressing EPs as primary mechanism of CLA resistance.
PubMed: 38923553
DOI: 10.1002/ardp.202400296 -
Pathogens (Basel, Switzerland) Jun 2024subspecies (MAP) infection leads to chronic, persistent granulomatous enteritis, causing prolonged diarrhoea and emaciation. The disease is managed using medications...
subspecies (MAP) infection leads to chronic, persistent granulomatous enteritis, causing prolonged diarrhoea and emaciation. The disease is managed using medications such as antibiotics, live vaccines, mycobacteriophage therapies and other treatments; however, a notable proportion of affected animals do not show improvement with this approach. We hypothesise that immunoinhibitory receptors TIM-3 (T cell immunoglobulin mucin protein-3) and PD-1 (Programmed death receptor 1) may be upregulated on Peripheral blood mononuclear cells (PBMCs) of MAP-seropositive bovines, potentially contributing to immune exhaustion. Samples (blood and faeces) were collected from 32 diarrhoeic bovines suspected of MAP infection; eight apparently healthy buffaloes from the dairy farm at Hisar, Haryana and from 14 cows (suffering from chronic diarrhoea, weakness and emaciation) housed in stray cattle shed. MAP infection was estimated using indigenous ELISA (i-ELISA), faecal IS PCR, culture and acid-fast staining. TIM-3 and PD-1 gene expression on PBMCs were determined using qRT-PCR. TIM3 expression was relatively higher (~400-fold, 330-fold, 112-fold, 65-fold and 16-fold) in 5 chronically diarrhoeic PBMCs samples (MAP-seropositive), and higher PD-1 expression (around ~7-fold, 1.75-fold, 2.5-fold, 7.6-fold) was recorded in 4 diarrhoeic MAP-seropositive animals, compared to apparently healthy and other MAP-seronegative diarrhoeic animals. High co-expression of TIM-3 and PD-1 levels was also recorded in chronically diarrhoeic, emaciated stray cattle. Understanding immune responses in field conditions might aid in the therapeutic management of
PubMed: 38921771
DOI: 10.3390/pathogens13060473 -
Microbiology Spectrum Jun 2024() as well as nontuberculous mycobacteria are intracellular pathogens whose treatment is extensive and increasingly impaired due to the rise of mycobacterial drug...
UNLABELLED
() as well as nontuberculous mycobacteria are intracellular pathogens whose treatment is extensive and increasingly impaired due to the rise of mycobacterial drug resistance. The loss of antibiotic efficacy has raised interest in the identification of host-directed therapeutics (HDT) to develop novel treatment strategies for mycobacterial infections. In this study, we identified amiodarone as a potential HDT candidate that inhibited both intracellular and in primary human macrophages without directly impairing bacterial growth, thereby confirming that amiodarone acts in a host-mediated manner. Moreover, amiodarone induced the formation of (auto)phagosomes and enhanced autophagic targeting of mycobacteria in macrophages. The induction of autophagy by amiodarone is likely due to enhanced transcriptional regulation, as the nuclear intensity of the transcription factor EB, the master regulator of autophagy and lysosomal biogenesis, was strongly increased. Furthermore, blocking lysosomal degradation with bafilomycin impaired the host-beneficial effect of amiodarone. Finally, amiodarone induced autophagy and reduced bacterial burden in a zebrafish embryo model of tuberculosis, thereby confirming the HDT activity of amiodarone . In conclusion, we have identified amiodarone as an autophagy-inducing antimycobacterial HDT that improves host control of mycobacterial infections.
IMPORTANCE
Due to the global rise in antibiotic resistance, there is a strong need for alternative treatment strategies against intracellular bacterial infections, including () and non-tuberculous mycobacteria. Stimulating host defense mechanisms by host-directed therapy (HDT) is a promising approach for treating mycobacterial infections. This study identified amiodarone, an antiarrhythmic agent, as a potential HDT candidate that inhibits the survival of and in primary human macrophages. The antimycobacterial effect of amiodarone was confirmed in an tuberculosis model based on infection of zebrafish embryos. Furthermore, amiodarone induced autophagy and inhibition of the autophagic flux effectively impaired the host-protective effect of amiodarone, supporting that activation of the host (auto)phagolysosomal pathway is essential for the mechanism of action of amiodarone. In conclusion, we have identified amiodarone as an autophagy-inducing HDT that improves host control of a wide range of mycobacteria.
PubMed: 38916320
DOI: 10.1128/spectrum.00167-24 -
Frontiers in Veterinary Science 2024Wildlife represents an increasingly important source of pathogens of medical and veterinary importance. Surveillance in wildlife offers an insight on current...
INTRODUCTION
Wildlife represents an increasingly important source of pathogens of medical and veterinary importance. Surveillance in wildlife offers an insight on current epidemiological status of selected pathogens and help to prevent spillovers to humans and livestock.
MATERIAL AND METHODS
Our study included 312 wild ruminants belonging to five species: Roe deer ( = 134), red deer ( = 113), Alpine chamois ( = 53), European mouflon ( = 10) and Alpine ibex ( = 2). Seven pathogens that may have profound effect on human/livestock health and economic viability of the farms were tested using serological methods.
RESULTS
Antibodies against spp., subsp. (MAP) and were detected in 34.62% (108/312), 0.96% (3/312), 2.24% (7/312), 0, 0.96% (3/312), 0, 0.64% (2/312) of animals tested, respectively. Because of low prevalences, risk factors were assessed only for . Sex (female>male) and species (roe deer>red deer, roe deer>Alpine chamois) were significantly associated with the positive outcome, while age was not.
DISCUSSION
Adult males had the lowest prevalence which offers future research opportunities. The lower seroprevalence of most investigated pathogens suggests game meat, if properly cooked, as being relatively safe for human consumption. This is the first study investigating the seroprevalence and associated risk factors of selected pathogens in wild ruminants in Slovenia.
PubMed: 38915887
DOI: 10.3389/fvets.2024.1415304 -
Cureus Jun 2024X-linked inhibitor of apoptosis (XIAP) deficiency is a rare primary immunodeficiency with a broad spectrum of clinical manifestations, including susceptibility to...
X-linked Inhibitor of Apoptosis (XIAP) Deficiency Complicated by Hemophagocytic Lymphohistiocytosis on Immunotherapy Leading to Acute Respiratory Distress Syndrome and Multiorgan Failure Secondary to Opportunistic Infections.
X-linked inhibitor of apoptosis (XIAP) deficiency is a rare primary immunodeficiency with a broad spectrum of clinical manifestations, including susceptibility to hemophagocytic lymphohistiocytosis (HLH), inflammatory bowel disease (IBD), hypogammaglobulinemia, and severe infections. We present a case of a 39-year-old male with a past medical history of XIAP deficiency complicated by HLH, Crohn's disease, and hypogammaglobulinemia, who developed acute respiratory distress syndrome (ARDS) due to Pneumocystis jiroveci pneumonia (PJP) and concurrent multiorgan failure due to disseminated Mycobacterium avium intracellulare (MAI) infection. This case highlights the challenges in managing XIAP deficiency, emphasizing the importance of early recognition, and the need for further research to improve outcomes in this population.
PubMed: 38912075
DOI: 10.7759/cureus.62703 -
Journal of Ethnopharmacology Jun 2024Indian system of Traditional medicine, AYUSH (Ayurveda, Yoga, Unani, Siddha, and Homeopathy) has great potential with a History of Safe Use (HOSU) of thousands of... (Review)
Review
ETHNOPHARMACOLOGICAL RELEVANCE
Indian system of Traditional medicine, AYUSH (Ayurveda, Yoga, Unani, Siddha, and Homeopathy) has great potential with a History of Safe Use (HOSU) of thousands of medicinal plants included in pharmacopoeias. The multi-targeted approach of phytoconstituents present in different traditionally used medicinal plants makes them suitable candidates for research against various infective pathogens. MAP which is a dairy-borne pathogen is associated with the development of Johne's disease in ruminants and Crohn's disease like autoimmune disorders in human beings. There are no reliable treatment alternatives available against MAP, leaving surgical removal of intestines as the sole option. Hence, there exists an urgent need to search for leads against such infection.
AIM OF THE STUDY
The present review has been conducted to find out the ethnopharmacological evidence about the potential of phytoconstituents against Mycobacterium avium subspecies paratuberculosis (MAP), along with the proposal of a potential phyto-MAP mechanism for the very first time taking anti-inflammatory, immunomodulatory, and anti-microbial traditional claims into consideration.
MATERIALS AND METHODS
We have analyzed and reviewed different volumes of the two main traditional scriptures of India i.e. Ayurvedic Pharmacopoeia of India (API) and Unani Pharmacopoeia of India (UPI), respectively-for identification of potential anti-MAP plants based on their claims for related disorders. These plants were further investigated systematically for their scientific publications of the last 20 years (2002-2022) available through electronic databases including Google Scholar, Pubmed, and Scopus. The studies conducted in vitro, cell lines, and in vivo levels were taken into consideration along with the associated mechanisms of phytoconstituents.
RESULTS
A total of 70 potential medicinal plants have been identified. Based on the ethnopharmacology, a potential phyto-paratuberculosis (Phyto-paraTB) mechanism has been proposed and out of 70, seven potential anti-MAP plants have been identified to have a great future as anti-MAP.
CONCLUSION
A novel and scientifically viable plan has been proposed for addressing anti-MAP plants for stimulating research against MAP and related disorders using mass-trusted AYUSH medicine, which can be used as an alternative remedy in resistance cases otherwise can be advocated as an adjuvant with modern treatments for better management of the disease.
PubMed: 38908495
DOI: 10.1016/j.jep.2024.118482 -
International Immunopharmacology Jun 2024Non-tuberculous mycobacterial pulmonary disease (NTM-PD) is caused by an imbalance between pathogens and impaired host immune responses. Mycobacterium avium complex...
OBJECTIVE
Non-tuberculous mycobacterial pulmonary disease (NTM-PD) is caused by an imbalance between pathogens and impaired host immune responses. Mycobacterium avium complex (MAC) and Mycobacterium abscessus (MAB) are the two major pathogens that cause NTM-PD. In this study, we sought to dissect the transcriptomes of peripheral blood immune cells at the single-cell resolution in NTM-PD patients and explore potential clinical markers for NTM-PD diagnosis and treatment.
METHODS
Peripheral blood samples were collected from six NTM-PD patients, including three MAB-PD patients, three MAC-PD patients, and two healthy controls. We employed single-cell RNA sequencing (scRNA-seq) to define the transcriptomic landscape at a single-cell resolution. A comprehensive scRNA-seq analysis was performed, and flow cytometry was conducted to validate the results of scRNA-seq.
RESULTS
A total of 27,898 cells were analyzed. Nine T-cells, six mononuclear phagocytes (MPs), and four neutrophil subclusters were defined. During NTM infection, naïve T-cells were reduced, and effector T-cells increased. High cytotoxic activities were shown in T-cells of NTM-PD patients. The proportion of inflammatory and activated MPs subclusters was enriched in NTM-PD patients. Among neutrophil subclusters, an IFIT1 neutrophil subcluster was expanded in NTM-PD compared to healthy controls. This suggests that IFIT1+ neutrophil subcluster might play an important role in host defense against NTM. Functional enrichment analysis of this subcluster suggested that it is related to interferon response. Cell-cell interaction analysis revealed enhanced CXCL8-CXCR1/2 interactions between the IFIT1+ neutrophil subcluster and NK cells, NKT cells, classical mononuclear phagocytes subcluster 1 (classical Mo1), classical mononuclear phagocytes subcluster 2 (classical Mo2) in NTM-PD patients compared to healthy controls.
CONCLUSIONS
Our data revealed disease-specific immune cell subclusters and provided potential new targets of NTM-PD. Specific expansion of IFIT1 neutrophil subclusters and the CXCL8-CXCR1/2 axis may be involved in the pathogenesis of NTM-PD. These insights may have implications for the diagnosis and treatment of NTM-PD.
PubMed: 38901242
DOI: 10.1016/j.intimp.2024.112412