In vitro comparison of human plasma-based and self-assembled tissue-engineered skin substitutes: two different manufacturing processes for the treatment of deep and difficult to heal injuries Sierra Sánchez, Álvaro Magne, Brice Savard, Etienne Martel, Christian Ferland, Karel Barbier, Martin A. Demers, Anabelle Larouche, Danielle Arias Santiago, Salvador Antonio Germain, Lucie Biomaterials Burn Fibrin This study has been funded by the Instituto de Salud Carlos III through the project PI17/02083 (co-funded by the European Regional Development Fund “A way to make Europe”), the Regional Government of Andalusia (PIGE-0242-2019), the Canadian Institutes for Health Research (CIHR) (FDN-143213 and IC-132948), the Fondation des Pompiers du Québec pour les Grands Brûlés (FPQGB) and the Quebec Network for Cell, Tissue and Gene Therapy—ThéCell (a thematic network supported by the Fonds de Recherche du Québec—Santé [FRQS]). The work of Álvaro Sierra-Sánchez was supported by a predoctoral fellowship and a mobility aid funded by the Instituto de Salud Carlos III (co-funded by the European Social Fund “Investing in your future”) with the dossier numbers FI18/00269 and MV20/00043, respectively. This study is part of his doctoral research in the Biomedicine’s program of University of Granada. The work of Brice Magne was supported by a postdoctoral fellowship funded by the FRQS. Karel Ferland and Anabelle Demers were supported by a Master studentship funded by the FRQS. Lucie Germain is the recipient of a Tier 1 Canadian Research Chair in Stem Cells and Tissue Engineering and a Research Chair on Tissue-Engineered Organs and Translational Medicine from the Fondation de l’Université Laval. Background: The aim of this in vitro study was to compare side-by-side two models of human bilayered tissue-engineered skin substitutes (hbTESSs) designed for the treatment of severely burned patients. These are the scaffold-free self-assembled skin substitute (SASS) and the human plasma-based skin substitute (HPSS). Methods: Fibroblasts and keratinocytes from three humans were extracted from skin biopsies (N = 3) and cells from the same donor were used to produce both hbTESS models. For SASS manufacture, keratinocytes were seeded over three self-assembled dermal sheets comprising fibroblasts and the extracellular matrix they produced (n = 12), while for HPSS production, keratinocytes were cultured over hydrogels composed of fibroblasts embedded in either plasma as unique biomaterial (Fibrin), plasma combined with hyaluronic acid (Fibrin-HA) or plasma combined with collagen (Fibrin-Col) (n/biomaterial = 9). The production time was 46-55 days for SASSs and 32-39 days for HPSSs. Substitutes were characterized by histology, mechanical testing, PrestoBlue™-assay, immunofluorescence (Ki67, Keratin (K) 10, K15, K19, Loricrin, type IV collagen) and Western blot (type I and IV collagens). Results: The SASSs were more resistant to tensile forces (p-value < 0.01) but less elastic (p-value < 0.001) compared to HPSSs. A higher number of proliferative Ki67+ cells were found in SASSs although their metabolic activity was lower. After epidermal differentiation, no significant difference was observed in the expression of K10, K15, K19 and Loricrin. Overall, the production of type I and type IV collagens and the adhesive strength of the dermal-epidermal junction was higher in SASSs. Conclusions: This study demonstrates, for the first time, that both hbTESS models present similar in vitro biological characteristics. However, mechanical properties differ and future in vivo experiments will aim to compare their wound healing potential. 2026-01-22T11:14:45Z 2026-01-22T11:14:45Z 2023 journal article Sierra Sánchez, A.; Magne, B.; Savard, E.; [et al.]. (2023). In vitro comparison of human plasma-based and self-assembled tissue-engineered skin substitutes: two different manufacturing processes for the treatment of deep and difficult to heal injuries. Burns & Trauma, Volume 11, 2023, tkad043, https://doi.org/10.1093/burnst/tkad043 2321-3876 https://hdl.handle.net/10481/110092 10.1093/burnst/tkad043 eng http://creativecommons.org/licenses/by-nc-nd/4.0/ open access Attribution-NonCommercial-NoDerivatives 4.0 Internacional Oxford Academic