Authors

Discussion

Huntington’s disease (HD) is a fatal neurodegenerative disorder caused by the expansion of a CAG repeat in the Huntingtin gene (HTT), leading to the expression of a mutant protein (mHTT) with an expanded polyglutamine domain near its N-terminus. A major advance in the study of HD has been the development of disease models employing human induced pluripotent stem cells (hiPSCs) either derived from patients with HD or engineered to develop isogenic lines with varying numbers of CAG repeats.

Current therapeutics in development involve small molecule splicing modulators or use of novel biological agents such as ASOs and RNAi and therefore, physiologically relevant and scalable models of HD are needed to improve outcomes and efficiency of drug development. The cell reprogramming technology, opti-ox^TM, in combination with CRISPR-Cas9 gene editing has been used to develop iPSC-derived ioGlutamatergic Neurons carrying HTT mutation with 50 CAG repeat. We have used high content imaging analysis and branched DNA assay to characterize HTT 50 CAG/WT ioGlutamatergic Neurons together with their isogenic control. Moreover, preliminary functional data using Multi Electrode Array (MEA) platform showed that HTT 50 CAG/WT neurons displayed impaired neuronal maturation and differences in the network metrics compared to isogenic control. Additionally, using a Design of Experiment (DoE) approach we have established a neuronal HTRF assay using ioGlutamatergic HTT 50 CAG/WT neurons that provides optimal conditions to screen compounds aiming to lower mHTT protein.