The potential use of induced pluripotent stem cells (iPSCs) in personalized regenerative medicine applications may be augmented by transgenics, including the expression of constitutive cell labels, differentiation reporters, or modulators of disease phenotypes. Thus, there is precedence for reproducible transgene expression amongst iPSC sub-clones with isogenic or diverse genetic backgrounds. Using virus or transposon vectors, transgene integration sites and copy numbers are difficult to control, and nearly impossible to reproduce across multiple cell lines. Moreover, randomly integrated transgenes are often subject to pleiotropic position effects as a consequence of epigenetic changes inherent in differentiation, undermining applications in iPSCs. To address this, we have adapted popular TALEN and CRISPR/Cas9 nuclease technologies in order to introduce transgenes into pre-defined loci and overcome random position effects. AAVS1 is an exemplary locus within the PPP1R12C gene that permits robust expression of CAG promoter-driven transgenes. Gene targeting controls transgene copy number such that reporter expression patterns are reproducible and scalable by ∼2-fold. Furthermore, gene expression is maintained during long-term human iPSC culture and in vitro differentiation along multiple lineages. Here, we outline our AAVS1 targeting protocol using standardized donor vectors and construction methods, as well as provide practical considerations for iPSC culture, drug selection, and genotyping.

Autosomal dominant lateral temporal epilepsy (ADLTE) is an inherited epileptic syndrome, and it is associated with mutations of leucine-rich glioma inactivated 1 (LGI1) gene. The underlying mechanisms of ADLTE are still unknown, as human neurons are difficult to obtain as a research tool. Human induced pluripotent stem cells (iPSCs) allow the generation of patient-derived neuronal cells in a dish, and can be a promising tool to model ADLTE. Here, we report the establishment of human iPSCs from an ADLTE patient carrying LGI1 mutation (c.1418C>T, p.Ser473Leu).

Skeletal muscle (SkM) supports the skeletal system and provides movement to everyday life and tasks; other vital roles include breathing, regulation of body temperature and defecation. Primary culture of human SkM cells is one of the important resources for clarifying human-specific development and pathomechanisms, although access to this resource is limited. In the last decades, the advent of human embryonic stem cells (ESCs) provided a human resource with unlimited self-renewal and the ability to differentiate into any type of somatic cells. 1 Many methods to differentiate human pluripotent stem cells, including human ESCs-and human-induced pluripotent stem cells