mycobacterium avium
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Author(s):  
Taylor L. T. Wherry ◽  
Rohana Dassanayake ◽  
Eduardo Casas ◽  
Shankumar Mooyottu ◽  
John P. Bannantine ◽  
...  

Mycobacterium avium subspecies paratuberculosis (MAP), the causative agent of ruminant enteritis, targets intestinal macrophages. During infection, macrophages contribute to mucosal inflammation and development of granulomas in the small intestine which worsens as disease progression occurs. Vitamin D3 is an immunomodulatory steroid hormone with beneficial roles in host-pathogen interactions. Few studies have investigated immunologic roles of 25-hydroxyvitamin D3 (25(OH)D3) and 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) in cattle, particularly cattle infected with MAP. This study examined the effects of exogenous vitamin D3 on immune responses of monocyte derived macrophages (MDMs) isolated from dairy cattle naturally infected with MAP. MDMs were pre-treated with ± 100 ng/ml 25(OH)D3 or ± 4 ng/ml 1,25(OH)2D3, then incubated 24 hrs with live MAP in the presence of their respective pre-treatment concentrations. Following treatment with either vitamin D3 analog, phagocytosis of MAP by MDMs was significantly greater in clinically infected animals, with a greater amount of live and dead bacteria. Clinical cows had significantly less CD40 surface expression on MDMs compared to subclinical cows and noninfected controls. 1,25(OH)2D3 also significantly increased nitrite production in MAP infected cows. 1,25(OH)2D3 treatment played a key role in upregulating secretion of pro-inflammatory cytokines IL-1β and IL-12 while downregulating IL-10, IL-6, and IFN-γ. 1,25(OH)2D3 also negatively regulated transcripts of CYP24A1, CYP27B1, DEFB7, NOS2, and IL10. Results from this study demonstrate that vitamin D3 compounds, but mainly 1,25(OH)2D3, modulate both pro- and anti-inflammatory immune responses in dairy cattle infected with MAP, impacting the bacterial viability within the macrophage.


2022 ◽  
Vol 36 (1) ◽  
pp. 7-15
Author(s):  
Takeo Togo ◽  
Jun Atsumi ◽  
Kiyomi Shimoda ◽  
Miyako Hiramatsu ◽  
Yuji Shiraishi

Author(s):  
Wassihun Wedajo Aragaw ◽  
Nicole Cotroneo ◽  
Suzanne Stokes ◽  
Michael Pucci ◽  
Ian Critchley ◽  
...  

Clinical emergence of resistance to new antibiotics affects their utility. Characterization of in vitro resistance is a first step in the profiling of resistance properties of novel drug candidates.


Medicina ◽  
2022 ◽  
Vol 58 (1) ◽  
pp. 110
Author(s):  
An-Che Cheng ◽  
Te-Yu Lin ◽  
Ning-Chi Wang

Antiretroviral therapy (ART) can restore protective immune responses against opportunistic infections (OIs) and reduce mortality in patients with human immunodeficiency virus (HIV) infections. Some patients treated with ART may develop immune reconstitution inflammatory syndrome (IRIS). Mycobacterium avium complex (MAC)-related IRIS most commonly presents as lymphadenitis, soft-tissue abscesses, and deteriorating lung infiltrates. However, neurological presentations of IRIS induced by MAC have been rarely described. We report the case of a 31-year-old man with an HIV infection. He developed productive cough and chronic inflammatory demyelinating polyneuropathy (CIDP) three months after the initiation of ART. He experienced an excellent virological and immunological response. Sputum culture grew MAC. The patient was diagnosed with MAC-related IRIS presenting as CIDP, based on his history and laboratory, radiologic, and electrophysiological findings. Results: Neurological symptoms improved after plasmapheresis and intravenous immunoglobulin (IVIG) treatment. To our knowledge, this is the first reported case of CIDP due to MAC-related IRIS. Clinicians should consider MAC-related IRIS in the differential diagnosis of CIDP in patients with HIV infections following the initiation of ART.


2022 ◽  
Vol 12 (1) ◽  
Author(s):  
Sepideh Hosseiniporgham ◽  
Lucio Rebechesu ◽  
Pierangela Pintore ◽  
Stefano Lollai ◽  
Maria Dattena ◽  
...  

AbstractParatuberculosis is an incurable gastroenteritis among ruminants that is promoted by Mycobacterium avium subsp. paratuberculosis (MAP), an acid-fast mycobacterium. To accelerate the detection of viable pathogen, a conventional (peptide mediated magnetic separation: PMS) and novel (phage-bead qPCR: PBQ) phage based assay was optimized. A superior limit of detection (LOD) of 10 MAP per 10 mL milk was suggested for PBQ compared to 100 cells/10 mL for PMS-phage assay. Via PBQ, viable MAP was found in 48.78% out 41 unpasteurized sheep and goat milk samples. Sheep milk samples (n = 29) that were tested by PMS-phage assay contained no viable MAP. The absence of viable MAP in milk collected from 21 of the recent sheep animals was also confirmed by PBQ after a 2-week gap. Although, the two phage assays comparably detected no viable MAP in the milk samples, MAP DNA and antibodies against MAP were recognized in milk and sera of some of these animals within two instances of sampling representing that some sheep animals were MAP shedders. In conclusion, PBQ and PMS-phage could be promising methods for the assessment of MAP viability in milk samples. However, PBQ was privileged over the PMS-phage assay due to the lower LOD, rapidity, higher sensitivity, lack of need to M. smegmatis and consequent virucidal treatment that are essential in PMS-phage assay for making lawn and inactivation of exogenous mycobacteriophages respectively.


2022 ◽  
Author(s):  
Andries J van Tonder ◽  
Huw C Ellis ◽  
Colin P Churchward ◽  
Kartik Kumar ◽  
Newara Ramadan ◽  
...  

Non-tuberculous mycobacteria (NTM) are ubiquitous environmental microorganisms and opportunistic pathogens in individuals with pre-existing lung conditions such as cystic fibrosis (CF) and non-CF bronchiectasis (BX). Whilst recent studies of Mycobacterium abscessus have identified transmission within single CF centres as well as nationally and globally, transmission of other NTM species is less well studied. We sequenced 1000 Mycobacterium avium complex (MAC) isolates from CF and non-CF patients at the Royal Brompton Hospital (RBH), London. Epidemiological links were identified from patient records. Previously published genomes were used to characterise global population structures. Analysis of the three most predominant MAC species identified putative transmission clusters that contained patients with CF, BX and other lung conditions, although few epidemiological links could be identified. For M. avium, lineages were largely limited to single countries, whilst for M. chimaera, global transmission clusters previously associated with heater cooler units (HCUs) were found. However, the origin of the major HCU-associated outbreak was a lineage already circulating in patients with pre-existing lung conditions. CF and non-CF patients share transmission chains even in the presence of CF patient-focussed hospital control measures, although the lack of epidemiological links suggests that most transmission is indirect and may be due to environmental foci or else asymptomatic carriage in the wider population. The major HCU-associated M. chimaera lineage being derived from an already circulating lineage, suggests that HCUs are not the sole vector nor the ultimate source of this lineage. Future studies should include sampling of environmental reservoirs and potential asymptomatic carriers.


2022 ◽  
Vol 2022 ◽  
pp. 1-4
Author(s):  
Masashi Ito ◽  
Akihiro Yoshii ◽  
Takashi Osaki ◽  
Tomohito Kuwako ◽  
Ei Yamaki ◽  
...  

The space around the staple line after lung surgery is at high risk of nontuberculosis Mycobacterium pulmonary disease (NTM-PD). Solitary nodules of NTM-PD around the staple line are difficult to distinguish from lung cancer. There is no clear identification from laboratory data and radiologic findings without histological examination. In the present case, we misdiagnosed the pulmonary granulomas with Mycobacterium avium complex pulmonary disease (MAC-PD) as a recurrence of lung cancer. We conducted radiation therapy. The pulmonary granulomas with MAC-PD were exacerbated by irradiation. The effects of radiation therapy for MAC-PD are unknown. When radiation therapy is performed for the patient coexistence with MAC-PD, we should pay attention to exacerbation of MAC-PD.


Author(s):  
Takahiro Kawasaki ◽  
Seigo Kitada ◽  
Kiyoharu Fukushima ◽  
Eri Akiba ◽  
Kako Haduki ◽  
...  

To satisfy the microbiologic criteria of the current diagnostic guideline for nontuberculous mycobacterial pulmonary disease (PD), at least two positive sputum cultures of the same species of mycobacteria from sputum are required to avoid the casual isolation of mycobacteria. This study showed that the positivity of a serum anti-glycopeptidolipid (GPL)-core IgA antibody test has an excellent diagnostic ability among patients with radiologically suspected Mycobacterium avium complex (MAC)-PD or Mycobacterium abscessus (MAB)-PD who already had a single positive sputum culture test.


2022 ◽  
Vol 12 ◽  
Author(s):  
Yanhong Bao ◽  
Yu Yao ◽  
Zi Wang ◽  
Shuiyin Wu ◽  
Xiuyun Jiang ◽  
...  

Mycobacterium avium subsp. paratuberculosis (MAP) is the pathogen of Johne’s disease (paratuberculosis), which mainly causes chronic infectious granulomatous enteritis in ruminants and has brought huge economic losses to animal husbandry. As a specific intracellular pathogen, when MAP invades the body, it is internalized by macrophages where it is able to replicate by inhibition of the phagosome maturation, escaping the host immune system and surviving, which leads to the spread of the disease. More recent studies have shown that circRNA is involved in many pathological and physiological processes of the body as the molecular sponge of miRNA, the scaffold of RNA binding protein and having the characteristic of being able to translate into protein. In this study, the mRNA and circRNA expression profiles of MAP-infected bovine monocyte-macrophages and uninfected bovine cells were analyzed by high-throughput sequencing. A total of 618 differentially expressed mRNA were screened out, including 322 upregulated mRNA and 296 downregulated mRNA. In addition, the analysis of circRNA differential expression profile showed 39 differentially expressed genes including 12 upregulated and 27 downregulated genes. Moreover, differential genes belonging to cytokine activity, chemokine activity, inflammatory reaction, apoptosis, and other functional groups related to macrophage immune response were significantly enriched in Gene Ontology (GO). Multiple signal pathways including NF-κB, MAPK, Toll-like receptor, IL-17, JAK-STAT, and other signaling pathways related to activating macrophage immune response were significantly enriched in Kyoto Encyclopedia of Genes and Genomes (KEGG). In addition, RT-qPCR technology verified the accuracy of the mRNA sequencing results. In this study, we have obtained the transcriptome information of mRNA and circRNA of bovine monocyte-macrophage infected with MAP. These results will provide data support for the further study of mRNA–miRNA–circRNA network and immune escape mechanism of MAP and will enrich the knowledge of the molecular immune mechanisms of Johne’s disease as well.


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