Protective efficacy of orally administered, heat-killed Lactobacillus pentosus b240 against influenza A virus

Sci Rep. 2013:3:1563. doi: 10.1038/srep01563.


Influenza A(H1N1)pdm virus caused the first human pandemic of the 21st century. Although various probiotic Lactobacillus species have been shown to have anti-microbial effects against pneumonia-inducing pathogens, the prophylactic efficacy and mechanisms behind their protection remain largely unknown. Here, we evaluated the prophylactic efficacy of heat-killed Lactobacillus pentosus b240 against lethal influenza A(H1N1)pdm virus infection in a mouse model. To further define the protective responses induced by b240, we performed virologic, histopathologic, and transcriptomic analyses on the mouse lungs. Although we did not observe an appreciable effect of b240 on virus growth, cytokine production, or histopathology, gene expressional analysis revealed that oral administration of b240 differentially regulates antiviral gene expression in mouse lungs. Our results unveil the possible mechanisms behind the protection mediated by b240 against influenza virus infection and provide new insights into probiotic therapy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Oral
  • Animals
  • Antiviral Agents / administration & dosage
  • Antiviral Agents / therapeutic use*
  • Cell Line
  • Chemokines / metabolism
  • Cytokines / metabolism
  • Dogs
  • Early Growth Response Protein 1 / biosynthesis
  • Female
  • Immunity, Innate / drug effects*
  • Immunity, Innate / immunology
  • Influenza A Virus, H1N1 Subtype
  • Lactobacillus*
  • Lung / virology
  • Madin Darby Canine Kidney Cells
  • Mice
  • Mice, Inbred BALB C
  • Orthomyxoviridae Infections / therapy*
  • Orthomyxoviridae Infections / virology
  • Probiotics / administration & dosage
  • Probiotics / therapeutic use*


  • Antiviral Agents
  • Chemokines
  • Cytokines
  • Early Growth Response Protein 1
  • Egr1 protein, mouse