In the hair follicle, the dermal papilla (DP) and dermal sheath (DS) support and maintain
proliferation and differentiation of the epithelial stem cells that produce the hair fibre. In view
of their regulatory properties, in this study we investigated the interaction between hair follicle
dermal cells (DP and DS) and embryonic stem cells (ESCs), induced pluripotent stem cells
(iPSCs) and haematopoietic stem cells. We found that co-culture of follicular dermal cells with
ESCs or iPSCs supported their prolonged maintenance in an apparently undifferentiated state
as established by differentiation assays, immunocytochemistry and RT-PCR for markers of
undifferentiated ESCs. We further showed that cytokines that are involved in ESC support are
also expressed by cultured follicle dermal cells, providing a possible explanation for
maintenance of ES cell stemness in co-cultures. The same cytokines were expressed within
follicles in situ in a pattern more consistent with a role in follicle growth activities than stem cell
maintenance. Finally we show that cultured mouse follicle dermal cells provide good stromal
support for haematopoiesis in an established co-culture model. Human follicular dermal cells
represent an accessible and readily propagated source of feeder cells for pluripotent and
haematopoietic cells, and have potential for use in clinical applications.