Identification of Halophilic Microbes in Lung Fibrotic Tissue by Oligotyping

Area of Science:

• Pulmonology
• Microbiology
• Pathology

Background:

• Idiopathic pulmonary fibrosis (IPF) is a progressive, incurable lung disease with an unknown cause and poor prognosis.
• Increased microbial presence in bronchoalveolar lavage fluid is linked to poor outcomes in IPF patients, but the role of tissue-associated microbes is unclear.
• Tissue-associated microbes can impact host physiology and disease progression.

Purpose of the Study:

• To investigate the presence and types of microbes within fibrotic lung tissues.
• To compare the lung tissue microbiome in IPF patients with a mouse model of lung fibrosis.

Main Methods:

• Oligotyping was used to analyze the microbial communities in lung tissues from IPF patients and human transforming growth factor-β1 (TGF-β1) transgenic mice.
• Lung tissue samples from non-tumor-bearing areas of lung cancer patients were also analyzed.
• Microbial populations in wild-type (WT) littermates and TGF-β1 transgenic mice were compared.

Main Results:

• The phyla Firmicutes and the genus Clostridium were predominant in lung tissues from IPF and lung cancer patients.
• Genera Halomonas, Shewanella, Christensenella, and Clostridium were prevalent in lung tissues of IPF and lung cancer patients.
• Proteobacteria were abundant in lung tissues of both WT and TGF-β1 transgenic mice, with a higher abundance of Halomonas in transgenic mice.

Conclusions:

• This study identifies specific tissue-associated microbes in the lungs of IPF patients.
• The findings suggest a potential role for tissue-associated bacteria, such as Halomonas, in the pathogenesis of lung fibrosis.
• The study provides insights into the lung microbiome in fibrotic lung disease using both human and animal models.