Non-invasive image-based cytometry for high throughput NK cell cytolysis analysis

Area of Science:

• Immunology
• Cell Biology
• Biotechnology

Background:

• Natural Killer (NK) cells are crucial lymphocytes for innate immunity, targeting transformed or infected cells.
• Traditional NK cell cytotoxicity assays are often low-throughput, destructive, and lack temporal resolution, limiting their in vivo relevance.
• Existing methods struggle to accurately assess NK cell function in complex 3D microenvironments.

Purpose of the Study:

• To evaluate a novel, non-invasive, quantitative image-based cytometry (qIBC) assay for NK cell cytotoxicity.
• To compare the qIBC assay's performance against established flow cytometry and fluorescence-based assays.
• To assess the qIBC assay's capability in 2D and 3D cell culture models, including spheroids.

Main Methods:

• Development and validation of a quantitative image-based cytometry (qIBC) assay.
• Comparison of qIBC with standard flow cytometry and fluorescence-based cytotoxicity assays.
• Application of qIBC to assess NK cell-mediated killing in 2D cultures and 3D spheroids.

Main Results:

• The qIBC assay demonstrated reproducible detection of NK cell-mediated target cell killing across various effector-to-target ratios with reduced variability.
• The qIBC assay successfully detected NK cell cytolysis in 3D spheroids, enabling scalable measurements.
• Performance of qIBC was comparable to established methods but offered advantages in 3D and non-invasive measurement.

Conclusions:

• Quantitative image-based cytometry is a suitable method for high-throughput screening of NK cell cytolysis in vitro.
• The qIBC assay facilitates the study of NK cell function in 3D models that better mimic in vivo tissue environments.
• This assay advances the ability to study NK cell-mediated killing with improved scalability and relevance.