Induction of Hair Follicle Dermal Papilla Cell Properties in Human Induced Pluripotent Stem Cell-Derived Multipotent LNGFR(+)THY-1(+) Mesenchymal Cells

In the 2017 study, researchers developed a method to differentiate human induced pluripotent stem cells (hiPSCs) into mesenchymal cells (iMCs) with characteristics of human dermal papilla (DP) cells, which are essential for hair follicle development and regeneration. They identified a subset of iMCs with LNGFR(+)THY-1(+) expression that, when treated with retinoic acid and DP cell activating culture medium, upregulated DP markers and interacted with human keratinocytes to promote hair follicle-related gene expression and hair shaft-like structure formation in vivo. These induced DP-substituting cells (iDPSCs) also responded to minoxidil sulfate, indicating their potential for use in hair follicle bioengineering and hair disease drug screening. The study involved a total of 56 mice across seven independent experiments, with specific numbers for different cell types: 28 mice for human DP cells, 4 for LNGFR(+)THY-1(+) iMCs, and 24 for iDPSCs. Despite these promising results, the iDPSCs did not consistently form distinct cell aggregates or induce hair structures as effectively as human DP cells, suggesting the need for further refinement of the induction protocol.