Application note: A high-throughput, radioactivity-free assay for cell-mediated cytotoxicity

In this application note, IntelliCyt Corporation demonstrate a fast, efficient, radioactivity-free CMC assay with low sample input requirements, enabling miniaturisation to 384-well plates, using the iQue® Screener…

Immunotherapy promises to be a powerful approach for treating a variety of diseases—most notably cancer.1–5However, development of novel immunotherapeutics has been limited by the lack of high-throughput methods to screen for effective molecular entities or, in the case of adoptive cell therapy, genetically engineered cells. Most current assays that measure cell-mediated cytotoxicity (CMC), such as the chromium release assay, are difficult to perform on large numbers of samples, can only report on a single biological readout like cell membrane integrity, and cannot differentiate between effector and target cells. Methods based on flow cytometry, such as the CFSE assay, 6 can assess CMC at the level of an individual cell and enable discrimination between effector cells and target cells. Traditional flow cytometry is slow, however, making it unsuitable for use as a high throughput screening (HTS) assay.

Here we demonstrate a fast, efficient, radioactivity-free CMC assay with low sample input requirements, enabling miniaturisation to 384-well plates. Using the iQue® Screener and differential labeling of effector and target cells, this method can capture multiple facets of biology—apoptosis markers, signal transduction markers, cell permeability, proliferative capability, and more—in a single well, providing a rich and highly quantitative data set specific to each cell type present. With this approach, researchers and drug discovery teams can quickly screen through compounds and conditions, building a detailed understanding of the molecular events occurring in each well and speeding insight into development of immunotherapeutic approaches.