Affinity molecular assay for detecting Candida albicans using chitin affinity and RPA-CRISPR/Cas12a

Nat Commun. 2024 Oct 28;15(1):9304. doi: 10.1038/s41467-024-53693-5.

Abstract

Invasive fungal infections (IFIs) pose a significant threat to immunocompromised individuals, leading to considerable morbidity and mortality. Prompt and accurate diagnosis is essential for effective treatment. Here we develop a rapid molecular diagnostic method that involves three steps: fungal enrichment using affinity-magnetic separation (AMS), genomic DNA extraction with silicon hydroxyl magnetic beads, and detection through a one-pot system. This method, optimized to detect 30 CFU/mL of C. albicans in blood and bronchoalveolar lavage (BAL) samples within 2.5 h, is approximately 100 times more sensitive than microscopy-based staining. Initial validation using clinical samples showed 93.93% sensitivity, 100% specificity, and high predictive values, while simulated tests demonstrated 95% sensitivity and 100% specificity. This cost-effective, highly sensitive technique offers potential for use in resource-limited clinical settings and can be easily adapted to differentiate between fungal species and detect drug resistance.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Proteins
  • Bronchoalveolar Lavage Fluid / microbiology
  • CRISPR-Associated Proteins
  • CRISPR-Cas Systems
  • Candida albicans* / genetics
  • Candida albicans* / isolation & purification
  • Candidiasis / diagnosis
  • Candidiasis / microbiology
  • Chitin* / metabolism
  • DNA, Fungal / genetics
  • Endodeoxyribonucleases / genetics
  • Endodeoxyribonucleases / metabolism
  • Humans
  • Sensitivity and Specificity

Substances

  • Chitin
  • DNA, Fungal
  • Cas12a protein
  • Endodeoxyribonucleases
  • Bacterial Proteins
  • CRISPR-Associated Proteins

Associated data

  • BioProject/PRJNA1172925
  • PDB/5DHD
  • PDB/5DHE
  • PDB/4A02
  • PDB/3A4W
  • PDB/2CWR
  • PDB/3N11
  • PDB/2RTT
  • PDB/1WVU
  • SRA/SRX26403238
  • SRA/SRX26403237
  • SRA/SRX26403236