Abstract
Objective The development of an in vitro platform for modeling human skin injury and the re-epithelization process.
Approach A fibrin provisional matrix (FPM) was installed into a wound facsimile of a bioprinted human skin equivalent (HSE). A mixture of plasma-derived fibrinogen-containing factor XIII, fibronectin, thrombin, and macrophages (an FPM “bioink”) was extruded into the wound site. The surrounding in vitro tissue culture became a source of keratinocytes to achieve wound closure by a re-epithelialization process signaled by the FPM.
Results An in vitro analog of wound closure and re-epithelialization by keratinocytes occurred over the FPM after a normal migration initiation at 3 days.
Innovation A physiologic mixture of macrophage/fibrinogen/fibronectin that supports macrophage differentiation was applied to a mechanically wounded, bioprinted dermal tissue. We developed a transitional culture medium to mimic the changing microenvironment during the initial phases of wound healing. As a reference, we temporally compared our in vitro model with a murine skin wound healing.
Conclusion This co-culture model was shown to temporally synchronize a re-epithelization process for initiation of keratinocyte migration from a surrounding tissue and the migration process over the top of an FPM. A future study of the analogous subepithelial healing pathway is envisioned using the same in vitro bioprinted tissue study platform for co-culture of keratinocytes, melanocytes, fibroblasts, endothelial cells, and macrophages using more specialized FPMs.
Competing Interest Statement
The authors have declared no competing interest.
Footnotes
Financial support: Coordination of Improvement of Higher-Level Personnel of Brazil (CAPES)
Abbreviations and Acronyms
- FPM
- Fibrin Provisional Matrix
- HSE
- Human Skin Equivalent
- pFN
- Plasma Fibronectin
- HUVEC
- Human Endothelial Cells
- IMDM
- Iscove’s Modified Dulbecco’s Medium
- HEPES BSS
- HEPES Buffered Saline Solution
- PFA
- Paraformaldehido
- EC
- Endothelial Cells