Dataset Information

Pathological granuloma fibrosis induced by agar-embedded Mycobacterium abscessus in C57BL/6JNarl mice.

ABSTRACT:

Introduction

Pulmonary granuloma diseases caused by Mycobacterium abscessus (M. abscessus) have increased in past decades, and drug-resistance in this pathogen is a growing public health concern. Therefore, an animal model of chronic granuloma disease is urgently needed.

Methods

In this study, M. abscessus embedded within agar beads (agar-AB) was used to develop such a model in C57BL/6JNarl mice.

Results

Chronic infection was sustained for at least 3 months after agar-AB infection, visible granulomas spread in the lungs, and giant cells and foamy cells appeared in the granulomas. More importantly, pulmonary fibrosis progressed for 3 months, and collagen fibers were detected by Masson trichrome staining. Further, inducible nitric oxide synthase (iNOS) was highly expressed within the alveolar space, and the fibrosis-mediator transforming growth factor beta (TGF-β) began to be expressed at 1 month. Hypoxia-inducible factor (HIF-1α) expression also increased, which aided in normalizing oxygen partial pressure.

Discussion

Although the transient fibrosis persisted for only 3 months, and the pulmonary structure resolved when the pathogen was cleard, this pulmonary fibrosis model for M. abscessus infection will provide a novel test platform for development of new drugs, regimens, and therapies.

SUBMITTER: Yang SJ

PROVIDER: S-EPMC10749312 | biostudies-literature | 2023

REPOSITORIES: biostudies-literature

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Publications

Pathological granuloma fibrosis induced by agar-embedded <i>Mycobacterium abscessus</i> in C57BL/6JNarl mice.

Yang Shiu-Ju SJ Hsu Chih-Hao CH Lai Chi-Yun CY Tsai Pei-Chu PC Song Yung-Deng YD Yeh Chang-Ching CC Chen Yih-Yuan YY Dou Horng-Yunn HY

Frontiers in immunology 20231211

<h4>Introduction</h4>Pulmonary granuloma diseases caused by <i>Mycobacterium abscessus</i> (<i>M. abscessus</i>) have increased in past decades, and drug-resistance in this pathogen is a growing public health concern. Therefore, an animal model of chronic granuloma disease is urgently needed.<h4>Methods</h4>In this study, <i>M. abscessus</i> embedded within agar beads (agar-AB) was used to develop such a model in C57BL/6JNarl mice.<h4>Results</h4>Chronic infection was sustained for at least 3 mo ...[more]

PMID: 38146374

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