Adenoviral gene transfer of a mutant surfactant enzyme ameliorates pseudomonas-induced lung injury

Gene Ther. 2006 Jun;13(12):974-85. doi: 10.1038/sj.gt.3302746. Epub 2006 Mar 2.

Abstract

Surfactant deficiency is an important contributor to the acute respiratory distress syndrome, a disorder that commonly occurs after bacterial sepsis. CTP:phosphocholine cytidylyltransferase (CCTalpha) is the rate-limiting enzyme required for the biosynthesis of dipalmitoylphosphatidylcholine (DPPC), the major phospholipid of surfactant. In this study, a cDNA encoding a novel, calpain-resistant mutant CCTalpha enzyme was delivered intratracheally in mice using a replication-deficient adenovirus 5 CTP:phosphocholine cytidylyltransferase construct (Ad5-CCT(Penta)) in models of bacterial sepsis. Ad5-CCT(Penta) gene transfer produced high-level CCTalpha gene expression, increased alveolar surfactant (DPPC) levels and improved lung surface tension and pressure-volume relationships relative to control mice. Pseudomonas aeruginosa (PA103) decreased DPPC synthesis, in part, via calpain-mediated degradation of CCTalpha. Deleterious effects of Pseudomonas on surfactant were lessened after infection with a mutant strain lacking the type III exotoxin, Exo U. Replication-deficient adenovirus 5 CTP:phosphocholine cytidylyltransferase gene delivery improved lung biophysical properties by optimizing surface activity in this Pseudomonas model of proteinase-mediated lung injury. The studies are the first demonstration of in vivo gene transfer of a lipogenic enzyme resulting in improved lung mechanics. The studies suggest that augmentation of DPPC synthesis via gene delivery of CCTalpha can attenuate impaired lung function in surfactant-deficient states such as bacterial sepsis.

Publication types

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

MeSH terms

  • 1,2-Dipalmitoylphosphatidylcholine / metabolism
  • Acute Disease
  • Adenoviridae / genetics
  • Animals
  • Calcium-Binding Proteins / genetics
  • Calcium-Binding Proteins / metabolism
  • Choline-Phosphate Cytidylyltransferase / administration & dosage
  • Choline-Phosphate Cytidylyltransferase / genetics*
  • Genetic Therapy / methods*
  • Genetic Vectors / administration & dosage
  • Genetic Vectors / genetics
  • Lung / enzymology
  • Lung Diseases / enzymology
  • Lung Diseases / therapy*
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Pseudomonas Infections / enzymology
  • Pseudomonas Infections / therapy*
  • Pulmonary Surfactants / administration & dosage*
  • Transduction, Genetic / methods

Substances

  • Calcium-Binding Proteins
  • Pulmonary Surfactants
  • 1,2-Dipalmitoylphosphatidylcholine
  • calpastatin
  • Choline-Phosphate Cytidylyltransferase