STAIN-FREE, RAPID, AND QUANTITATIVE VIRAL PLAQUE ASSAY USING DEEP LEARNING AND HOLOGRAPHY

Smart overview of the Invention

A novel viral plaque assay device employs lens-free holographic imaging combined with deep learning to rapidly and accurately detect viral plaque formations. This stain-free method captures phase and amplitude information of the plaques within sample wells without the need for labels. A neural network is trained to identify cell lysing events caused by viral replication, achieving a detection rate of over 90% with 100% specificity in less than 20 hours, significantly reducing the time compared to traditional assays that require at least 48 hours.

Technical Field

The device pertains to the field of viral plaque assays, particularly focusing on an automated, rapid, and stain-free quantitative approach. It leverages lens-free holographic imaging and deep learning, offering a cost-effective and compact solution. This technology reduces the incubation time necessary for traditional plaque assays while maintaining their benefits over other virus quantification methods.

Background

Viral infections present a major global health challenge, affecting millions annually through diseases like influenza and COVID-19. Accurate and low-cost virus quantification is crucial for clinical diagnosis and vaccine development. Traditional plaque assays, despite being the gold standard for virus quantification, are time-consuming and prone to human error. Recent advancements in quantitative phase imaging and deep learning offer promising solutions for improving these assays.

Device and Method

The device comprises a sample holder with wells for incubating samples with cells, illuminated by laser diodes or LEDs. Image sensors capture holographic images over various incubation times, which are processed by software to create phase and amplitude images. A trained neural network analyzes these images to produce PFU probability maps, identifying plaque-forming units and virus-infected areas. This method was validated with viruses like VSV, HSV-1, and EMCV, achieving early detection and significant time savings.

Applications and Benefits

This automated, label-free device provides rapid and quantitative PFU readouts, applicable to various plaque assays in virology. It facilitates early detection of viral infections and may accelerate vaccine and drug development research. The system's compact design and low cost (under $880, excluding a laptop) make it accessible for widespread use, offering a 10-fold larger dynamic range of virus concentration than standard assays without additional sample preparation.