Abstract 4146: Unlocking IO drug potential by high content imaging of immune cell co-cultures with cancer organoids from diverse cancer indications
Authors: de Man Saskia , Foini Chiara , Veenendaal Tomas , Kop Michelle , Santaris Christos , Abiega Sergei Chavez , Beztsinna Nataliia , Okkes Daniel , Weterings Ashgard , Price Leo , Goverse Gera 
Published: April 2023

Abstract
Introduction
Immuno-oncology (IO) drugs have shown great results for specific cancer indications in the clinic, most notably for hematological cancers, as well as some solid cancers such as melanoma. However, the potential of many IO drugs as well as mechanisms of resistance in different indications remain to be uncovered. With the development of organoid technology, it is now possible to grow tumor objects in 3D scaffolds with a high resemblance to the original patient tumor in terms of genetics, transcriptomics and morphology. This technology is highly suited for pre-clinical screens and of great translational value. Here we present a high throughput platform using this organoid technology to study IO drug candidates in different indications.
Material and methods
Patient-derived organoids (PDOs) from different origins, including colorectal, lung, breast, melanoma and ovarian cancers, were cultured in protein hydrogels. Allogenic PBMCs were isolated from two healthy donors and were activated with superantigens or CD3/CD28 beads. PDOs and PBMCs were then co-cultured together in presence of IO drugs, such as monoclonal and bispecific antibodies, and analyzed for immune cell migration, infiltration and PDO killing. This was assessed by 3D high content imaging (HCI) and quantified with an automated image segmentation pipeline, which segments tumor objects and immune cells in the 3D reconstituted stack.
Results and discussion
Image-based analysis on PBMC numbers, migration and infiltration, and PDO volumes was performed. Data analysis showed that the activation status of the PBMCs induced different levels of infiltration and killing, as measured by the number of infiltrated immune cells and PDO volumes respectively. In addition, different PDOs showed different sensitivities for immune cell-mediated killing and compound effects.
Conclusion
Our PDO - immune cell co-culture system in combination with HCI allows the detection and quantification of migration towards, infiltration into and killing effects of immune cells on PDOs in a single assay. This 3D assay allows the identification of IO drug mode of action, specificity, resistance and sensitivity and immune cell activation. Here, we observed a broad spectrum of responses based on the specific characteristics (e.g. morphology and gene expression) of different PDOs and differential activation of PBMCs. The broad range of PDOs available from our biobanks empowers IO drug developers to explore their candidates in multiple cancer indications or in multiple models of a single indication with a range of different genetics, target expression and morphology. Ultimately this allows for the testing of IO drugs, such as engineered T Cells, tumor targeting antibodies, bispecific T Cell engagers, and immune cell modulators in clinically relevant models, bringing the promise of IO therapies to more indications and patients.
Citation Format: Saskia de Man, Chiara Foini, Tomas Veenendaal, Michelle Kop, Christos Santaris, Sergei Chavez Abiega, Nataliia Beztsinna, Daniel Okkes, Ashgard Weterings, Leo Price, Gera Goverse. Unlocking IO drug potential by high content imaging of immune cell co-cultures with cancer organoids from diverse cancer indications. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4146.