Gene-silencing antisense oligomers inhibit acinetobacter growth in vitro and in vivo

Bruce L. Geller, Kimberly Marshall-Batty, Frederick J. Schnell, Mattie M. McKnight, Patrick L. Iversen, David E. Greenberg

Research output: Contribution to journalArticle

37 Scopus citations

Abstract

Background. Peptide-conjugated phosphorodiamidate morpholino oligomers (PPMOs) are synthetic DNA/ RNA analogues that silence expression of specific genes. We studied whether PPMOs targeted to essential genes in Acinetobacter lwoffii and Acinetobacter baumannii are active in vitro and in vivo. Methods. PPMOs were evaluated in vitro using minimum inhibitory concentration (MIC) and viability assays, and in vivo using murine pulmonary infection models with intranasal PPMO treatment. Results. MICs of PPMOs ranged from 0.1 to 64 μM (approximately 0.6-38 μg/mL). The most effective PPMO tested was (RXR) 4-AcpP, which is targeted to acpP. (RXR)4-AcpP reduced viability of A. lwoffii and A. baumannii by >103 colony-forming units/mL at 5-8 times MIC. Mice treated with ≥0.25 mg/kg of (RXR) 4-AcpP survived longer and had less inflammation and bacterial lung burden than mice treated with a scrambled-sequence PPMO or phosphate-buffered saline. Treatment could be delayed after infection and still increase survival. Conclusions. PPMOs targeted to essential genes of A. lwoffii and A. baumannii were bactericidal and had MICs in a clinically relevant range. (RXR) 4-AcpP increased survival of mice infected with A. lwoffii or A. baumannii, even when initial treatment was delayed after infection. PPMOs could be a viable therapeutic approach in dealing with multidrug-resistant Acinetobacter species.

Original languageEnglish (US)
Pages (from-to)1553-1560
Number of pages8
JournalJournal of Infectious Diseases
Volume208
Issue number10
DOIs
StatePublished - Nov 15 2013

    Fingerprint

Keywords

  • Acinetobacter
  • Antisense
  • Baumannii
  • Infection
  • Lwoffii
  • MIC
  • Mouse
  • Phosphorodiamidate morpholino oligomer
  • Ppmo
  • Respiratory infection

ASJC Scopus subject areas

  • Immunology and Allergy
  • Infectious Diseases

Cite this

Geller, B. L., Marshall-Batty, K., Schnell, F. J., McKnight, M. M., Iversen, P. L., & Greenberg, D. E. (2013). Gene-silencing antisense oligomers inhibit acinetobacter growth in vitro and in vivo. Journal of Infectious Diseases, 208(10), 1553-1560. https://doi.org/10.1093/infdis/jit460