A Novel iPSC Model of Parkinson’s Disease Based on IFNB-Knockout Mice

Background:Parkinson’s disease is an elusive condition causing the loss of dopaminergic neurons in the Substantia Nigra with not much being known about its underlying mechanisms. Despite many efforts to model this disease both in vivo and in vitro, until recently none have been completely successful. We have used cells from the recently developed mouse model based on the knockout of Interferon beta to create induced pluripotent stem cells (iPSCs) which were then differentiated to dopaminergic neurons. After characterizing their Parkinsonian phenotype a novel in vitro model for Parkinson’s disease was developed. Materials and Methods:iPSCs were generated from both KO and WT mouse-fibroblasts using retroviral induction of the four Yamanaka factors Oct4, Sox2, KLF4 and C-Myc. The generated iPSCs were characterized using Alkaline phosphatase assay as well as immunofluorescence and qRT-PCR to confirm the expression for pluripotency factors. After characterization these cells were differentiated to dopaminergic neurons using the dual SMAD inhibition method of neural induction. Complete differentiation to functional dopaminergic neurons were assessed using immunofluorescence for Tyrosine Hydroxylase, and GIRK2 and electrophysiological tests (patch clamp). Immunofluorescence imaging using an antibody against phosphorylated Alpha-Synuclein was used to check for Lewy bodies.Results:Our results show the aggregation of phosphorylated alpha-synuclein which is the hallmark of Parkinson’s disease in the the KO neurons, as detected using immunofluorescence, but not in the neurons differentiated from WT iPSCs.Conclusion:This model is the only model to date which exhibits Lewy body formation in vitro, we have an unprecedented opportunity to study the mechanisms of Parkinson’s disease The setup of this procedure allows individuals identified as being at risk of this disease to be tested using in vitro modeling. If they are found to be susceptible, drug screening can be used to tailor a personalized treatment.

Keywords:

Parkinson’s Disease , IPS model , Disease Modeling , Interferon Beta