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Host-to-Host Transmission of Streptococcus pneumoniae Is Driven by Its Inflammatory Toxin, Pneumolysin

M Ammar Zafar1, Yang Wang2, Shigeto Hamaguchi1

  • 1Department of Microbiology, New York University, New York, NY 10016, USA.

Cell Host & Microbe
|January 13, 2017
PubMed

Insights

Streptococcus pneumoniae transmission relies on inflammation and bacterial shedding. Pneumolysin toxin drives inflammation, increasing shedding and environmental survival for new host transmission.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Pathogenesis

Background:

  • Host-to-host transmission is essential for pathogen propagation.
  • Streptococcus pneumoniae is an opportunistic pathogen requiring effective transmission strategies.

Purpose of the Study:

  • To investigate the mechanisms of Streptococcus pneumoniae transmission in a mouse model.
  • To elucidate the role of pneumolysin in transmission and host-pathogen interaction.

Main Methods:

  • Utilized an infant mouse model for studying Streptococcus pneumoniae transmission.
  • Quantified bacterial shedding in nasal secretions and assessed inflammatory responses.
  • Investigated the necessity and sufficiency of pneumolysin in promoting transmission.

Main Results:

  • High bacterial shedding and acute inflammatory response were critical for transmission.
  • Pneumolysin was essential and sufficient to induce inflammation, increase shedding, and enable transmission.
  • Transmission occurred without direct contact, suggesting an environmental reservoir.
  • Pneumolysin enhanced bacterial survival outside the host.

Conclusions:

  • Pneumolysin-induced inflammation facilitates Streptococcus pneumoniae transmission by increasing shedding and environmental survival.
  • This study reveals a microbial strategy for host transit, explaining the expression of damaging toxins.

Keywords:
bacteriacolonizationinfectionpneumococcuspneumolysinsheddingtoxintransmission

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