RE:Shiseido and Replicel Have Cured BaldnessShiseido's patent described a different culturing method, and more importantly creating an immortalized DPC through gene editing.
Here's an abstract published a few years ago from another research team that discovered a method to enable DPC cells to maintain function in vitro.
https://pubs.rsc.org/en/Content/ArticleLanding/2016/TB/C5TB02265G#!divAbstract