Generation and immunofluorescent validation of gene knockouts in adult human colonic organoids using multi-guide RNA CRISPR-Cas9.

While readily achieved in cell lines, the application of CRISPR-Cas9 gene editing in human-derived organoids suffers from limited efficacy and complex protocols. Here, we describe a multi-guide RNA CRISPR-Cas9 gene-editing protocol which efficiently achieves complete gene knockout in adult human colonic organoids. This protocol also describes crucial steps including how to harvest patient tissue to maximize gene-editing efficacy and a technique to validate gene knockout following editing with immunofluorescent staining of the organoids against the target protein.

Utilizing panels of patient derived xenografts to aid the development of antibody drug conjugates.

Despite numerous endeavors in clinical trials there are few clinically approved Antibody Drug Conjugate (ADC) therapies. Here we comment on our recent publication demonstrating the power of using panels of patient-derived xenografts (PDX) prior to Phase 1, to assess the potential heterogeneity of response a clinical candidate may show across a population. Furthermore we discuss how the same approach has been used in an additional ADC program.