3D cell-printing technique has been

3D cell-printing technique has been under spotlight as an appealing biofabrication platform due to itsability to precisely pattern living cells in pre-defined spatial locations. In skin tissue engineering, a majorremaining challenge is to seek for a suitable source of bioink capable of supporting and stimulatingprinted cells for tissue development. However, current bioinks for skin printing rely on homogeneousbiomaterials, which has several shortcomings such as insufficient mechanical properties and recapitulation of microenvironment. In this study, we investigated the capability of skin-derived extracellularmatrix (S-dECM) bioink for 3D cell printing-based skin tissue engineering. S-dECM was for the first timeformulated as a printable material and retained the major ECM compositions of skin as well as favorablegrowth factors and cytokines. This bioink was used to print a full thickness 3D human skin model. Thematured 3D cell-printed skin tissue using S-dECM bioink was stabilized with minimal shrinkage,whereas the collagen-based skin tissue was significantly contracted during in vitro tissue culture. Thisphysical stabilization and the tissue-specific microenvironment from our bioink improved epidermalorganization, dermal ECM secretion, and barrier function. We further used this bioink to print 3D prevascularized skin patch able to promote in vivo wound healing. In vivo results revealed that endothelial progenitor cells (EPCs)-laden 3D-printed skin patch together with adipose-derived stem cells (ASCs)accelerates wound closure, re-epithelization, and neovascularization as well as blood flow. We envisionthat the results of this paper can provide an insightful step towards the next generation source for bioinkmanufacturing.