Optimization Techniques of Single-Detergent Based Protocols for Heart Tissue Decellularization.

The extracellular matrix (ECM) scaffolds are considered a gold standard for the engineering of appropriate grafts used in regenerative medicine for tissue repair, and decellularization of myocardial tissue is one of the most studied processes for obtaining natural ECM to date. Decellularization methods, agents used, or treatment durations can be varied to optimize cardiac tissue decellularization parameters. In this work we performed a morphological and morphometric analysis of cardiac tissue subjected to decellularization protocols based on Sodium Deoxycholate (SD) or Sodium Lauryl Sulfate (SLS) to identify factors that allow optimization of single-detergent based protocols for cardiac ECM manufacturing. For this, Wistar rat hearts (n=10) were subjected to 5 different decellularization protocols (n=2) and then histologically processed to achieve H&E or Azan trichrome stained sections for the morphological and morphometric analysis of the obtained ECM. The results of this study showed that SLS alters the spatial distribution of cardiac ECM collagen fibers, and SD can be successfully used in tailoring single-based detergent decellularization protocols by appropriately adjusting the application times of hypo/hyperosmotic shocks, which increases the lytic action of the detergent, and the washing times for the efficient elimination of cellular residues.

Partial Decellularization as a Method to Improve the Biocompatibility of Heart Tissue Implants.

Increasing the biocompatibility of some biological implants through tissue engineering is important for regenerative medicine, which recently has a rapid development dynamic. In this study we used tree different washing protocols, respectively with Sodium Lauryl Sulfate (SLS), with Sodium Deoxycholate (SD), and with saline (Sa) to achieve partial decellularization of 2-3mm thick cross-sections through Wistar rat hearts. Pieces of the heart tissue were either histologically analyzed to evaluate the decellularization processes or implanted for 5 days on 9-day-old chick embryo chorioallantoic membrane (CAM) and then histologically analyzed to evaluate CAM-implant interactions. Histological analysis of SLS or SD washed tissues showed different microscopic features of the decellularization processes, SLS-washing leading to the formation of a completely decellularized ECM layer at the periphery of the heart tissue. Both detergents induced changes in the spatial arrangement of collagen fibers of the heart tissue. Histological analysis of the CAM implants shoved that the peripheral zone with complete decellularization induced by SLS increased the biocompatibility of heart tissue implants by favoring neovascularization and cell migration. These results suggested that the biocompatibility of the heart tissue implant can be modulated by the appropriate use of a SLS-based decellularization protocol.