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Inhibiting F-Actin Polymerization Impairs the Internalization of Moraxella catarrhalis

Jinhan Yu1,2,3, Jingjing Huang1,2,3, Rui Ding3

  • 1Department of Clinical Laboratory, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China.

Microorganisms
|February 24, 2024
PubMed

Insights

Moraxella catarrhalis phenotypes impact acute exacerbation of chronic obstructive pulmonary disease (AECOPD). This study reveals filamentous actin (F-actin) dynamics are crucial for M. catarrhalis internalization into lung cells.

Area of Science:

  • Microbiology
  • Pulmonology
  • Cell Biology

Background:

  • Moraxella catarrhalis is a nasopharyngeal commensal bacterium implicated in acute exacerbations of chronic obstructive pulmonary disease (AECOPD).
  • M. catarrhalis adheres to and invades respiratory epithelial cells via a macropinocytosis-like mechanism, with varying abilities observed among different bacterial phenotypes.
  • Understanding the factors influencing M. catarrhalis pathogenicity is crucial for managing AECOPD.

Purpose of the Study:

  • To investigate the factors influencing the pathogenicity of distinct Moraxella catarrhalis phenotypes in AECOPD.
  • To elucidate the role of actin cytoskeleton regulation in M. catarrhalis infection of lung epithelial cells.

Main Methods:

  • Utilized a murine COPD model and in vitro experiments.
  • Employed transcriptome sequencing, electron microscopy, and Western blot analyses.
  • Investigated the effect of inhibiting actin polymerization on M. catarrhalis internalization.

Main Results:

  • Transcriptome data suggested a link between actin cytoskeleton regulation and M. catarrhalis infection.
  • Electron microscopy and Western blots showed reduced filamentous actin (F-actin) upon M. catarrhalis infection.
  • Inhibition of actin polymerization impaired M. catarrhalis internalization, distinct from adhesion.

Conclusions:

  • Filamentous actin dynamics are essential for M. catarrhalis internalization into respiratory epithelial cells.
  • These findings offer theoretical insights for developing preventive strategies and personalized treatments for AECOPD patients.
  • Understanding M. catarrhalis phenotype-host interactions is vital for AECOPD management.
Keywords:
F-actinMoraxella catarrhalischronic obstructive pulmonary diseasecytoskeletonpolymerizationrespiratory epithelial cells

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