GMP-compliant culture of human hair follicle cells for encapsulation and transplantation

Human hair follicle cells, both bulge and dermal papilla cells, were isolated and cultured in a GMP cell factory, in order to obtain an in vitro hair follicle source for encapsulation end transplantation in alopecia regenerative cell therapy. An in vitro model, constituted by organotypic cultures of human skin sample, was set up to simulate the dermal-epidermal interaction between bulge cells and dermal papilla cells, evaluating the possible new follicles formation and the regenerative potentiality of these hair follicle cells. Both the bulge and dermal papilla cells show an excellent cellular proliferation as well as an abundant extracellular matrix production. The immunofluorescence investigation revealed the positivity of both cell lines to CK15 and CD200, whereas both cell lines were negative to CD71 and Oct-4. The pool of cultured bulge and dermal papilla cells was injected into the deep dermis; at day 28 of culture, some organized areas with a higher cell density can be observed: the cells self-organize into papilla-like lengthened aggregates. In samples in which the follicular cells have been seeded on the dermis surface, an epidermis-like homogeneous monolayer on the dermis surface can be seen, therefore showing a potentiality of these cells for epidermis regeneration. These data show the efficacy of a cellular isolation and amplification approach to obtain an in vitro human hair follicle regenerative source on industrial scale in a GMP cell factory. The results also proved an intrinsic potentiality of follicular cells to in vitro recreate the epidermis for tissue engineering purposes. Thus, it is feasible to produce bioengineered hair follicles in a GMP cell factory, for encapsulation and transplantation in alopecic patients.