Fig. 2

Generation and characterization of MDNS from POLG1^Q811R variant and healthy control iPSCs. a Schematic model illustrating the differentiation strategy employed to obtain MDNS. Images illustrate cell morphology at each stage. b Immunostaining for brain cell subtype markers GFAP and MAP2, midbrain marker FOXA2 and dopaminergic neuronal markers TH and VMAT, on cryosectioned MDNS aged 100 DIV and dissociated cultures aged 106 DIV. Nuclei are counterstained with DAPI. Scale bars: 100 μm. c Quantification of MAP2⁺, GFAP⁺ and TH⁺ cells relative to total number of DAPI-labeled cells, FOXA2⁺ and VMAT⁺ cells relative to TH-labeled cells in POLG1 variant and healthy control cultures. Results are presented as ± SEM; n = 4 independent experiments; * indicates p < 0.05; unpaired t-test. d Electrochemical chronoamperometric recordings showing DA release upon KCL stimulation by POLG1 variant and healthy control MDNS dissociated cultures