Oligonucleotide microarrays as novel tools in antibiotic resistance detection and human pathogen identification

  • Nöhammer, C. (Author)
  • Rudolf Pichler (Author)
  • V. Klose (Author)
  • Levente Bodrossy (Author)
  • Elisabeth Presterl (Author)

Activity: Talk or presentation / LecturePresentation at a scientific conference / workshop

Description

Accuracy coupled with speed is of greatest importance in diagnostics of infectious disease. This applies in particular when it comes to identifying infection causing bacteria and their antibiotic resistance in patients already under bad health conditions (immunocompromised, intensive care unit). In contrast to conventional diagnostic methods lasting at least 24 hrs due to their requirement for microbial growth, DNA-based methods meet here the needs for a fast, reliable and thereby life-saving diagnosis. We present here a novel approach for fast identification of antibiotic resistance and infectious bacteria by combining PCR amplification with subsequent microarray analysis. We established a prototype microarray for the detection of 12 different antibiotic resistance genes (ABR-ARChipTM). The diagnostic test is based on multiplex-PCR from genomic bacterial DNA, incorporation of fluorescently labelled nucleotides (dCTP-Cy5) during a primer extension step, subsequent hybridization onto a microarray containing specific oligonucleotide probes for the resistance genes to be analysed and final target detection by a laser scanner. The ABR-ARChipTM was tested with genomic DNA from numerous clinical isolates of Staphylococcus epidermidis showing various spectra of antibiotic resistance. Results obtained by microarray analysis were compared with those from conventional, phenotypic antibiotic resistance analysis performed by disk diffusion testing. In parallel to the ABR-ARChipTM prototype, currently adapted to specific clinical settings, we have recently started to develop a pathogen detection microarray including -at this initial stage- oligonucleotide probes for Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecium and Enterococcus faecalis - representing some of the most frequent pathogens in community- and hospital-acquired infections. The procedure here includes PCR amplification of the bacterial 16S rRNA gene with universal primers and subsequent hybridization of, by in vitro transcription generated, Cy3-labelled RNA target molecules onto a microarray, containing 16S rRNA gene-derived species -and genus specific oligonucleotide probes. From our results we conclude that DNA microarrays are useful and promising tools for rapid antibiotic resistance determination as well as pathogen identification. When applied in combination they are certainly most effective in infectious disease management.
Period15 May 2003
Event title2nd Array User Meeting
Event typeOther
Degree of RecognitionInternational

Research Field

  • Not defined