Validation of a quantitative PCR based detection system for indoor mold exposure assessment in bioaerosols

Area of Science:

• Environmental Science
• Molecular Biology
• Mycology

Background:

• Assessing airborne fungal particles is challenging due to limitations in current sampling and analytical methods.
• Comparing results from different techniques is difficult, hindering accurate indoor mold detection.

Purpose of the Study:

• To describe and validate a novel indoor mold detection system using quantitative polymerase chain reaction (qPCR).
• To assess the reliability and stability of the qPCR system for identifying airborne fungal particles.
• To compare the qPCR system's performance against traditional cultivation and high-throughput sequencing methods.

Main Methods:

• Development and validation of an indoor mold detection system based on qPCR.
• Testing the system with fungal DNA, spore suspensions, and bioaerosols under controlled conditions.
• Comparison of qPCR results with cultivation and high-throughput sequencing from indoor and outdoor air samples.

Main Results:

• The qPCR system requires spiking and normalization due to material loss and assay bias, with detection limits around 18 spores/sample for Tritirachium oryzae.
• Normalized qPCR measurements for fungal spore mixtures were 2-3 times higher than cultivation-based methods.
• qPCR showed good correlation with high-throughput sequencing (rho = 0.83) for indoor mold detection, excluding Cladosporium species.

Conclusions:

• The validated qPCR system demonstrates significant potential for improving the precision of indoor mold assessments.
• This system can complement existing culture-based approaches by providing more accurate and comprehensive fungal identification.
• The broad-range fungal community detection capability makes this qPCR system a promising alternative to high-throughput sequencing for indoor mold identification.