Characterization of neurons derived from chromosome 15q11-q13.1 duplication syndrome (Dup15q) induced pluripotent stem cells (iPSCs). (a) Immunocytochemistry for the neuronal marker MAP2 (red) indicates the presence of mature neurons in 10-week-old Idic1-8 iPSC-derived monolayer neuronal cultures. (b) S100β-positive astrocytes (red) are also present after 10 weeks of neural differentiation. (c) VGlut1-positive (green) excitatory and (d) GAD-65-positive (red) inhibitory neurons show a mixed population of neurons. (e) MAP2-positive (red) neurons are decorated with PSD-95 (green) and (e’) Synapsin (blue) puncta. (e”) Merged image showing co-localization of PSD-95 and Synapsin suggests the formation of functional synapses. Nuclei are counterstained with DAPI (blue). All scale bars are 20 μm.