3D bioprinting matrices with controlled pore structure and release function guide in vitro self-organization of sweat gland

Abstract

3D bioprinting matrices are novel platforms for tissue regeneration. Tissue self-organization is a critical process during regeneration that implies the features of organogenesis. However, it is not clear from the current evidences whether 3D printed construct plays a role in guiding tissue self-organization in vitro. Based on our previous study, we bioprinted a 3D matrix as the restrictive niche for direct sweat gland differentiation of epidermal progenitors by different pore structure (300-μm or 400-μm nozzle diameters printed) and reported a long-term gradual transition of differentiated cells into glandular morphogenesis occurs within the 3D construct in vitro. At the initial 14-day culture, an accelerated cell differentiation was achieved with inductive cues released along with gelatin reduction. After protein release completed, the 3D construct guide the self-organized formation of sweat gland tissues, which is similar to that of the natural developmental process. However, glandular morphogenesis was only observed in 300-μm–printed constructs. In the absence of 3D architectural support, glandular morphogenesis was not occurred. This striking finding made us to identify a previously unknown role of the 3D-printed structure in glandular tissue regeneration, and this self-organizing strategy can be applied to forming other tissues in vitro.

Diverse Applications of Nanomedicine

“…643,644 Cells can also be seeded into matrices resembling replicas of cell surfaces, 645 into decellularized matrices, 646 or even into completely synthetic scaffolds to improve their biocompatibility and engraftment. 647,648 There have been some attempts for translation to the clinic, 649,650 but results have been and are still heavily scrutinized. 651−653 The basic requirements such transplants need to fullfill involve vascularization, in order to warrant continuous blood supply, 654 and, in case of exposure to the environment ( e.g.…”

Three Dimensional Bioprinting of a Vascularized and Perfusable Skin Graft Using Human Keratinocytes, Fibroblasts, Pericytes, and Endothelial Cells

“…In addition, the matrix induced sweat gland regeneration when it was directly printed on burn wounds in mice. 20 Incorporation of pigment-producing melanocytes and immune cells in printed skin structures has also been reported. [21][22][23] Other approaches using 3D bioprinting technology have shown to successfully generate perfusable capillary-like structures in vitro.…”

From Shape to Function: The Next Step in Bioprinting

“…Homogenates from dermis of mice were also used as functional component of bioinks, when mixed directly into a gelatin/alginate blend, and then used to print porous constructs embedding epithelial progenitor cells (EPs). The homogenized tissue is rich in BMP‐4 (BMP = bone morphogenetic protein) and EGF, which are a major drive toward EP differentiation into functional sweat glands, and was demonstrated to induce the maturation of functional glands, that even restored partial sweating activity upon in vivo implantation in murine burn wound model . However, since homogenates, differently from dECM, may still have present immunogens, their compatibility should be carefully ensured prior to implantation in vivo.…”