Isolation and characterization of a "phiKMV-like" bacteriophage and its therapeutic effect on mink hemorrhagic pneumonia

PLoS One. 2015 Jan 23;10(1):e0116571. doi: 10.1371/journal.pone.0116571. eCollection 2015.

Abstract

The objective of this study was to investigate the potential of using phages as a therapy against hemorrhagic pneumonia in mink both in vitro and in vivo. Five Pseudomonas aeruginosa (P. aeruginosa) strains were isolated from lungs of mink with suspected hemorrhagic pneumonia and their identity was confirmed by morphological observation and 16S rDNA sequence analysis. Compared to P. aeruginosa strains isolated from mink with hemorrhagic pneumonia in 2002, these isolates were more resistant to antibiotics selected. A lytic phage vB_PaeP_PPA-ABTNL (PPA-ABTNL) of the Podoviridae family was isolated from hospital sewage using a P. aeruginosa isolate as host, showing broad host range against P. aeruginosa. A one-step growth curve analysis of PPA-ABTNL revealed eclipse and latent periods of 20 and 35 min, respectively, with a burst size of about 110 PFU per infected cell. Phage PPA-ABTNL significantly reduced the growth of P. aeruginosa isolates in vitro. The genome of PPA-ABTNL was 43,227 bp (62.4% G+C) containing 54 open reading frames and lacked regions encoding known virulence factors, integration-related proteins and antibiotic resistance determinants. Genome architecture analysis showed that PPA-ABTNL belonged to the "phiKMV-like Viruses" group. A repeated dose inhalational toxicity study using PPA-ABTNL crude preparation was conducted in mice and no significantly abnormal histological changes, morbidity or mortality were observed. There was no indication of any potential risk associated with using PPA-ABTNL as a therapeutic agent. The results of a curative treatment experiment demonstrated that atomization by ultrasonic treatment could efficiently deliver phage to the lungs of mink and a dose of 10 multiplicity of infection was optimal for treating mink hemorrhagic pneumonia. Our work demonstrated the potential for phage to fight P. aeruginosa involved in mink lung infections when administered by means of ultrasonic nebulization.

Publication types

  • Research Support, Non-U.S. Gov't
  • Retracted Publication

MeSH terms

  • Animals
  • Drug Administration Routes / veterinary
  • Drug Resistance, Bacterial
  • Genetic Vectors / administration & dosage
  • Genetic Vectors / adverse effects
  • Genome, Viral
  • Mice
  • Mink / microbiology*
  • Nebulizers and Vaporizers / veterinary
  • Pneumonia, Bacterial / microbiology
  • Pneumonia, Bacterial / therapy*
  • Pneumonia, Bacterial / veterinary
  • Podoviridae / physiology*
  • Pseudomonas Infections / therapy*
  • Pseudomonas Infections / veterinary
  • Pseudomonas aeruginosa / classification
  • Pseudomonas aeruginosa / growth & development*
  • Pseudomonas aeruginosa / isolation & purification*
  • Pseudomonas aeruginosa / virology
  • Sewage / virology

Substances

  • Sewage

Grants and funding

YPX received a grant supported by the National High Technology Research and Development Program (Grant No. 2013AA102805), URL: http://www.863.gov.cn/. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.