Live cell screening represents a major paradigm shift for the development of new pharmaceuticals and biologics. Despite the many automation and data analysis advances for this purpose, however, many challenges still hinder the implementation of this approach. As one set of examples, the most common cell cytotoxicity assays used to evaluate the efficacy of an antibody drug, the complement-dependent cytotoxicity (CDC) and antibody-dependent cellular cytotoxicity (ADCC) assays, only focus on end-point results. As a result, they yield little information about which cells are killed or resitant in a heterogeneous tumor population. In addition, none of the assay products offered today are compatible with the use of high content imaging to study the onset and rate of cytotoxicity, despite the rich quantity of data that this approach can provide. Adheren's new cell-array toxicity (CAT) assay platforms promise to advance this field by minimizing false positives, providing earlier cytotoxicity data, and allowing the visualization of cell death in real time. These producs are based on a core DNA-based cell attachment platform, which allows strong and programmable cell binding for a very wide range of cell types. The adhesion method allows both live and killed cells to be retained on the microarray, providing improved cytotoxicity statistics. This technology also allows the cell microarray to be washed without cell loss, and it enables the direct visualization of cell cytotoxicity over time using fluorescence imaging. This can providing unprecedented levels of real-time cell-specific data for the elucidation of complement- and effector cell-based cytotoxicity mechanisms. We propose to scale up and further develop these cell array-based ADCC and CDC microscopy assays by validating their effectiveness for a wide range of cell types and biological assays. In addition, the assay platform will be extended from currently the used glass bottom 96 well plates to include low-cost industry standard polystyrene 96 well plates.

Public Health Relevance

Two of the most important cell-based screening methods, the antibody-dependent cellular cytotoxicity (ADCC) assay and the complement-dependent cytotoxicity (CDC) assay, are used in all antibody therapeutic drug research to assess efficacy in vitro. There are several shortcomings associated with the current assay techniques, however, most significantly including a lack of information about drug-resistant tumor cells. The introduction of Adheren's cell-array toxicity (CAT) assay platforms will elevate antibody drug screening and cancer research to new levels of versatility and practicality at a time when thousands of researchers need better screening tools and millions of patients need more effective cancer treatments.

Agency
National Institute of Health (NIH)
Type
Exploratory/Developmental Grants Phase II (R33)
Project #
5R33CA174616-02
Application #
8739624
Study Section
Special Emphasis Panel (ZCA1)
Program Officer
Knowlton, John R
Project Start
Project End
Budget Start
Budget End
Support Year
2
Fiscal Year
2014
Total Cost
Indirect Cost
Name
Adheren, Inc.
Department
Type
DUNS #
City
Berkeley
State
CA
Country
United States
Zip Code
94705
Hsiao, Ching-Wen; Lo, Yen-Ting; Liu, Hong et al. (2014) Real-time cytotoxicity assays in human whole blood. J Vis Exp :e51941