Identification and development of TRPM4 antagonists to counteract neuronal excitotoxicity.

Neurodegeneration in central nervous system disorders is linked to dysregulated neuronal calcium. Direct inhibition of glutamate-induced neuronal calcium influx, particularly via N-methyl-D-aspartate receptors (NMDAR), has led to adverse effects and clinical trial failures. A more feasible approach is to modulate NMDAR activity or calcium signaling indirectly.

Generation of two isogenic human iPSC lines (ZIPi013-B-1, ZIPi013-B-2) carrying a CRISPR/Cas9-mediated deletion of TRPM4.

Two isogenic hiPSC lines, ZIPi013-B-1 and ZIPi013-B-2, were generated by CRISPR/Cas9-mediated indels in the TRPM4 gene of the previously published ZIPi013-B. TRPM4 belongs to the evolutionarily conserved family of transient receptor potential (TRP) channels. It is expressed ubiquitously and its activity is regulated by intracellular calcium binding, changes in membrane potential, phosphoinositide lipids in the plasma membrane and the local concentration of cytoplasmic ATP and ADP.

Human isogenic cells of the neurovascular unit exert transcriptomic cell type-specific effects on a blood-brain barrier in vitro model of late-onset Alzheimer disease.

Background: The function of the blood-brain barrier (BBB) is impaired in late-onset Alzheimer disease (LOAD), but the associated molecular mechanisms, particularly with respect to the high-risk APOE4/4 genotype, are not well understood. For this purpose, we developed a multicellular isogenic model of the neurovascular unit (NVU) based on human induced pluripotent stem cells.

Methods: The human NVU was modeled in vitro using isogenic co-cultures of astrocytes, brain capillary endothelial-like cells (BCECs), microglia-like cells, neural stem cells (NSCs), and pericytes.

Generation of a set of induced pluripotent stem cell lines from two Alzheimer disease patients carrying APOE4 (MLUi007-J; MLUi008-A) and healthy old donors carrying APOE3 (MLUi009-A; MLUi010-B) to study APOE in aging and disease.

Late-onset Alzheimer disease (LOAD) is the most frequent neurodegenerative disease, and the APOE ε4 allele is the most prominent risk factor for LOAD. Four human induced pluripotent stem cell (iPSC) lines MLUi007-J, MLUi008-B, MLUi009-A, and MLUi010-B were generated from LOAD patients and healthy matched donors by reprogramming of B-lymphoblastoid cells (B-LCLs) with episomal plasmids. The application of B-LCLs holds a great promise to model LOAD and other diseases because they can easily be generated from primary peripheral blood mononuclear cells (PBMCs) by infection with the Epstein-Barr virus (EBV).

High-content screening of mitochondrial polarization in neural cells derived from human pluripotent stem cells.

We present a high-content screening (HCS) protocol for quantifying mitochondrial activity in live neural cells from human induced pluripotent stem cells (iPSCs). The assessment is based on mitochondrial membrane potential, which is influenced by the efficiency of mitochondrial bioenergetics. We describe how to perform the analysis using both an HCS platform and the open-source software CellProfiler.

G9a dictates neuronal vulnerability to inflammatory stress via transcriptional control of ferroptosis.

Neuroinflammation leads to neuronal stress responses that contribute to neuronal dysfunction and loss. However, treatments that stabilize neurons and prevent their destruction are still lacking. Here, we identify the histone methyltransferase G9a as a druggable epigenetic regulator of neuronal vulnerability to inflammation.

The blood-brain barrier is dysregulated in COVID-19 and serves as a CNS entry route for SARS-CoV-2.

Neurological complications are common in COVID-19. Although SARS-CoV-2 has been detected in patients' brain tissues, its entry routes and resulting consequences are not well understood. Here, we show a pronounced upregulation of interferon signaling pathways of the neurovascular unit in fatal COVID-19.

Culturing human iPSC-derived neural progenitor cells on nanowire arrays: mapping the impact of nanowire length and array pitch on proliferation, viability, and membrane deformation.

Nanowire arrays used as cell culture substrates build a potent tool for advanced biological applications such as cargo delivery and biosensing. The unique topography of nanowire arrays, however, renders them a challenging growth environment for cells and explains why only basic cell lines have been employed in existing studies. Here, we present the culturing of human induced pluripotent stem cell-derived neural progenitor cells on rectangularly arranged nanowire arrays: In detail, we mapped the impact on proliferation, viability, and topography-induced membrane deformation across a multitude of array pitches (1, 3, 5, 10 μm) and nanowire lengths (1.

The CAD risk locus 9p21 increases the risk of vascular calcification in an iPSC-derived VSMC model.

Background: Coronary artery disease (CAD) is the leading cause of death worldwide. Chromosome locus 9p21 was the first to be associated with increased risk of CAD and coronary artery calcification (CAC). Vascular calcification increases the risk for CAD.

Human iPSC-Derived Blood-Brain Barrier Models: Valuable Tools for Preclinical Drug Discovery and Development?

Translating basic biological knowledge into applications remains a key issue for effectively tackling neurodegenerative, neuroinflammatory, or neuroendocrine disorders. Efficient delivery of therapeutics across the neuroprotective blood-brain barrier (BBB) still poses a demanding challenge for drug development targeting central nervous system diseases. Validated in vitro models of the BBB could facilitate effective testing of drug candidates targeting the brain early in the drug discovery process during lead generation.

Interfacing human induced pluripotent stem cell-derived neurons with designed nanowire arrays as a future platform for medical applications.

Nanostructured substrates such as nanowire arrays form a powerful tool for building next-generation medical devices. So far, human pluripotent stem cell-derived neurons-a revolutionary tool for studying physiological function and modeling neurodegenerative diseases-have not been applied to such innovative substrates, due to the highly demanding nature of stem cell quality control and directed differentiation procedures to generate specialized cell types. Our study closes this gap, by presenting electrophysiologically mature human pluripotent stem cell-derived neurons on a set of nanowires in different patterns and growth densities after only four weeks of maturation-thereof 14 to 16 days on the nanowire arrays.

Differentiation of human iPSCs into VSMCs and generation of VSMC-derived calcifying vascular cells.

Vascular calcification displays a major cause of death worldwide, which involve mainly vascular smooth muscle cells (VSMCs). Since 2007, there are increasing numbers of protocols to obtain different cell types from human induced-pluripotent stem cells (iPSCs), however a protocol for calcification is missing. Few protocols exist today for the differentiation of iPSCs towards VSMCs and none are known for their calcification.