A 3D image-based phenotypic screen of bi-specific antibodies targeting stem cells in a panel of patient derived colon carcinoma organoids.

e23174Background: Organoid cultures grown in 3D increase the likelihood for accurately predicting drug responses in patients, discriminating different drug responses and flagging toxicity. We used a high content screening platform and a panel of 40 patient derived colorectal cancer (CRC) organoids to characterize the responses to a large panel of (545) bispecific antibodies. These antibodies comprised a HER3 or EGFR targeting arm combined with a LGR4, LGR5, ZNRF3 or RNF43 targeting arm to target CRC stem cells. Methods: Automated 3D imaging and analysis of CRC organoids was performed. Results: The broad mutational spectrum of the organoids was reflected in a broad heterogeneity of organoid phenotypes. Some CRC organoids formed well-differentiated spheroids with a single lumen that resembled wild type organoids, whereas others had multiple lumens or were poorly differentiated without a luminal cavity. A rich set of morphological features was extracted from 3D image data, including organoid size and shape, ...