Electroporation-mediated delivery of FER gene enhances innate immune response and improves survival in a murine model of pneumonia

Gene Ther. 2018 Aug;25(5):359-375. doi: 10.1038/s41434-018-0022-y. Epub 2018 Jun 15.

Abstract

Previously, we reported that electroporation-mediated (EP) delivery of the FER gene improved survival in a combined trauma-pneumonia model. The mechanism of this protective effect is unknown. In this paper, we performed a pneumonia model in C57/BL6 mice with 500 CFU of Klebsiella pneumoniae. After inoculation, a plasmid encoding human FER was delivered by EP into the lung (PNA/pFER-EP). Survival of FER-treated vs. controls (PNA; PNA/EP-pcDNA) was recorded. In parallel cohorts, bronchial alveolar lavage (BAL) and lung were harvested at 24 and 72 h with markers of infection measured. FER-EP-treated animals reduced bacterial counts and had better 5-day survival compared to controls (80 vs. 20 vs. 25%; p < 0.05). Pre-treatment resulted in 100% survival. With FER, inflammatory monocytes were quickly recruited into BAL. These cells had increased surface expression for Toll-receptor 2 and 4, and increased phagocytic and myeloperoxidase activity at 24 h. Samples from FER electroporated animals had increased phosphorylation of STAT transcription factors, varied gene expression of IL1β, TNFα, Nrf2, Nlrp3, Cxcl2, HSP90 and increased cytokine production of TNF-α, CCL-2, KC, IFN-γ, and IL-1RA. In a follow-up experiment, using Methicillin-resistant Staphylococcus aureus (MRSA) similar bacterial reduction effects were obtained with FER gene delivery. We conclude that FER overexpression improves survival through STAT activation enhancing innate immunity and accelerating bacterial clearance in the lung. This constitutes a novel mechanism of inflammatory regulation with therapeutic potential in the setting of hospital-acquired pneumonia.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bacterial Load
  • Cytokines / metabolism
  • Disease Models, Animal
  • Electroporation / methods*
  • Female
  • Genetic Therapy / methods
  • Humans
  • Immunity, Innate / genetics
  • Klebsiella pneumoniae / isolation & purification
  • Methicillin-Resistant Staphylococcus aureus / isolation & purification
  • Mice
  • Mice, Inbred C57BL
  • Pneumonia, Bacterial / immunology
  • Pneumonia, Bacterial / microbiology
  • Pneumonia, Bacterial / therapy*
  • Protein-Tyrosine Kinases / administration & dosage
  • Protein-Tyrosine Kinases / biosynthesis
  • Protein-Tyrosine Kinases / genetics*
  • Protein-Tyrosine Kinases / immunology
  • Tumor Necrosis Factor-alpha / metabolism

Substances

  • Cytokines
  • Tumor Necrosis Factor-alpha
  • proto-oncogene protein c-fes-fps
  • Protein-Tyrosine Kinases