Disease modeling using induced pluripotent stem cells (iPSC)

Neurodevelopmental and neurodegenerative disorders have an incidence of at least 10% in Western populations. Little is known about the mechanisms and pathophysiology leading to the majority of these central nervous system disorders. To this end, we use induced pluripotent stem cell (iPSC) and CRISPR/Cas9 technologies to model neurogenesis and neuronal function. The objective is to understand disease mechanisms of the central nervous system associated with specific gene variants and, in the long-term, to interfere with these mechanisms in search for novel therapeutic strategies.

Production of iPSC

Microscope image of brain organoid
Brain organoid derived from iPSCs
after 3 months. The organoids
recapitulate formation of brain
structures in 3D. Cortical structures
(blue) are surrounded by meningeal
cells (red). Ventricular zone structures
are indicated with arrows.

Fibroblasts are reprogrammed into iPSC using non-integrating vectors expressing the four Yamanaka factors. Reprogramming is followed by differentiation into neuronal progenitor cells and different mature neuronal subpopulations in 2D as well as in 3D (brain organoids). Some fibroblasts are obtained from patients with well-defined neurodevelopmental disorders and known causative gene mutations whereas some are obtained from healthy controls and gene-edited by CRISPR/Cas9 to obtain isogenic lines.

Functional analyses and validation of neuronal cells comprise e.g. proliferation, apoptosis, migration, dendrite formation, electrophysiological properties, imaging techniques and high through-put analysis of biomarkers (transcriptome, proteome and methylome analysis) on bulk as well as single cells. Disorders that are currently modeled and under investigation are e.g. Down syndrome, Alzheimer’s disease, Dravet disease, Mowat-Wilson disease, Von Hippel-Lindau disease and Incontinentia Pigmenti. Disease-associated pathways/factors/biomarkers are validated for read-out assays and future screening of small compound libraries.