@article{KrajkaNaujockPaulyetal.2021,
  author    = {Krajka, Victor and Naujock, Maximilian and Pauly, Martje G. and Stengel, Felix and Meier, Britta and Stanslowsky, Nancy and Klein, Christine and Seibler, Philip and Wegner, Florian and Capetian, Philipp},
  title     = {Ventral Telencephalic Patterning Protocols for Induced Pluripotent Stem Cells},
  series = {Frontiers in Cell and Developmental Biology},
  volume    = {9},
  journal   = {Frontiers in Cell and Developmental Biology},
  issn      = {2296-634X},
  doi       = {10.3389/fcell.2021.716249},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-244607},
  year      = {2021},
  abstract  = {The differentiation of human induced pluripotent stem cells (hiPSCs) into specific cell types for disease modeling and restorative therapies is a key research agenda and offers the possibility to obtain patient-specific cells of interest for a wide range of diseases. Basal forebrain cholinergic neurons (BFCNs) play a particular role in the pathophysiology of Alzheimer's dementia and isolated dystonias. In this work, various directed differentiation protocols based on monolayer neural induction were tested for their effectiveness in promoting a ventral telencephalic phenotype and generating BFCN. Ventralizing factors [i.e., purmorphamine and Sonic hedgehog (SHH)] were applied at different time points, time intervals, and concentrations. In addition, caudal identity was prevented by the use of a small molecule XAV-939 that inhibits the Wnt-pathway. After patterning, gene expression profiles were analyzed by quantitative PCR (qPCR). Rostro-ventral patterning is most effective when initiated simultaneously with neural induction. The most promising combination of patterning factors was 0.5 μM of purmorphamine and 1 μM of XAV-939, which induces the highest expression of transcription factors specific for the medial ganglionic eminence, the source of GABAergic inter- and cholinergic neurons in the telencephalon. Upon maturation of cells, the immune phenotype, as well as electrophysiological properties were investigated showing the presence of marker proteins specific for BFCN (choline acetyltransferase, ISL1, p75, and NKX2.1) and GABAergic neurons. Moreover, a considerable fraction of measured cells displayed mature electrophysiological properties. Synaptic boutons containing the vesicular acetylcholine transporter (VACHT) could be observed in the vicinity of the cells. This work will help to generate basal forebrain interneurons from hiPSCs, providing a promising platform for modeling neurological diseases, such as Alzheimer's disease or Dystonia.},
  language  = {en}
}
@article{StengelVulinovicMeieretal.2020,
  author    = {Stengel, Felix and Vulinovic, Franca and Meier, Britta and Gr{\"u}tz, Karen and Klein, Christine and Capetian, Philipp},
  title     = {Impaired differentiation of human induced neural stem cells by TOR1A overexpression},
  series = {Molecular Biology Reports},
  volume    = {47},
  journal   = {Molecular Biology Reports},
  doi       = {10.25972/OPUS-24117},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-241177},
  pages     = {3993-4001},
  year      = {2020},
  abstract  = {DYT-TOR1A is the most common inherited dystonia caused by a three nucleotide (GAG) deletion (dE) in the TOR1A gene. Death early after birth and cortical anomalies of the full knockout in rodents underscore its developmental importance. We therefore explored the timed effects of TOR1A-wt and TOR1A-dE during differentiation in a human neural in vitro model. We used lentiviral tet-ON expression of TOR1A-wt and -dE in induced neural stem cells derived from healthy donors. Overexpression was induced during proliferation of neural precursors, during differentiation and after differentiation into mature neurons. Overexpression of both wildtype and mutated protein had no effect on the viability and cell number of neural precursors as well as mature neurons when initiated before or after differentiation. However, if induced during differentiation, overexpression of TOR1A-wt and -dE led to a pronounced reduction of mature neurons in a dose dependent manner. Our data underscores the importance of physiological expression levels of TOR1A as crucial for proper neuronal differentiation. We did not find evidence for a specific impact of the mutated TOR1A on neuronal maturation.},
  language  = {en}
}