Whole Cell Analysis (WCA)

A unique property of PNA FISH is the use of fluorescence-tagged molecular probes to target naturally amplified, genetic markers such ribosomal RNA (rRNA) or messenger RNA (mRNA) inside intact cells. There is no need to lyse the bacterial cells, isolate the genetic material or amplify target sequences which allows PNA FISH to overcome limitations of other molecular technologies such as PCR.

Whole Cell Analysis
(Molecular Charactierization)
ribosomal RNA
(Species Identification)
messenger RNA
(Antibiotic Resistance)


Features and Benefits of WCA Approach to Pathogen Identification

Features

Benefits
  • PNA Probes: Fast, highly specific and stable synthetic probe technology
  • Cellular analysis:  Detection of genetic targets inside intact cells.
  • Multiple genetic targets: Ribosomal RNA (rRNA) and messenger RNA (mRNA)
  • In vivo target amplification:  Natural amplification of genetic material
  • Multiplex: By fluorescence color and cell morphology
  • Single cell detection: If recovered or concentrated and then analyzed by PNA FISH
  • Quantification:  Cell count correlating to concentration in sample (CFU/mL)
  • Rapid and accurate detection in highly complex sample matrixes (e.g. blood)
  • Retains morphology and limits need for sample prep to isolate genetic material.
  • Gold standard for species identification and resistance detection inside single cell.
  • Avoid issues with amplicon contamination that lead to false positive results.
  • Detect multiple targets inside same cells as well as detect mixed populations of bacteria
  • High sensitivity (10-100 CFU/mL)
  • Discriminate between infection vs. colonization (e.g. Pneumonia and UTI)


Staphylococcus aureus (Whole Cells) from Positive Blood Culture