In Vitro Osteoblast Model for Bone Wound Infections and Antimicrobial Therapy

Abstract

We proposed to determine the changes in osteoblast differentiation in vitro when infected with multidrug resistant bacteria and the therapeutic effects of two well characterized antimicrobial peptides. For the first part of the study, an in vitro 3 dimensional(3D) model of primary human osteoblasts in a collagen scaffold was developed for infection. The 3D osteoblast cultures were infected with clinical isolates of multidrug resistant Acinetobacter baumannii, Klebsiella pneumoniae and Pseudomonas aeruginosa. Custom PCR arrays with genes associated with osteoblast differentiation/maturation were used to study gene expression in primary osteoblasts at several time points 4, 24, 48 and 72 hours post infection. The temporal gene expression patterns of infected osteoblasts in the 3D model were studied by real time PCR. Initial work suggested changes in the expression of osteoblast marker genes, several transcription factors, cell adhesion related genes and proinflammatory cytokines may contribute to an impediment for osteoblast differentiation and maturation when osteoblasts harbor any of these 3bacteria as intracellular pathogens. Antimicrobial therapy was tested with KSL-W peptide on osteoblasts in 3-D scaffolds and was effective against extracellular Acinetobacter baumannii and Klebsiella pneumoniae compared to uninfected controls. KSLW was not effective against Pseudomonas aeruginosa. KSL-W was not effective against intracellular bacteria. The outcome of our findings may contribute to accelerate treatment options and management of osteomyelitis due to drug resistant bacteria in the Wounded Warrior.

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Document Details

Document Type
Technical Report
Publication Date
Oct 01, 2012
Accession Number
AD1007323

Entities

People

  • Chrysanthi Paranavitana

Organizations

  • Geneva Foundation

Tags

Communities of Interest

  • Biomedical

DTIC Thesaurus Topics

  • Bacteria
  • Bacterial Infections And Mycoses
  • Biomedical Research
  • Genes
  • Genetic Phenomena
  • Growth (Physiology)
  • Infection
  • Osteoblasts
  • Pathogenic Bacteria
  • Physiological Phenomena
  • Physiological Processes
  • Wound Infections
  • Wounds And Injuries

Fields of Study

  • Biology
  • Medicine

Readers

  • Microbial Pathology
  • Oncology (Cancer Research).
  • Trauma Surgery or Emergency Medicine.