Processing of Human Cardiac Tissue Toward Extracellular Matrix Self-assembling Hydrogel for <em>In Vitro</em> and <em>In Vivo</em> Applications

Abstract

Acellular extracellular matrix preparations are useful for studying cell-matrix interactions and facilitate regenerative cell therapy applications. Several commercial extracellular matrix products are available as hydrogels or membranes, but these do not possess tissue-specific biological activity. Because perfusion decellularization is usually not possible with human heart tissue, we developed a 3-step immersion decellularization process. Human myocardial slices procured during surgery are first treated with detergent-free hyperosmolar lysis buffer, followed by incubation with the ionic detergent, sodium dodecyl sulfate, and the process is completed by exploiting the intrinsic DNase activity of fetal bovine serum. This technique results in cell-free sheets of cardiac extracellular matrix with largely preserved fibrous tissue architecture and biopolymer composition, which were shown to provide specific environmental cues to cardiac cell populations and pluripotent stem cells. Cardiac extracellular matrix sheets can then be further processed into a microparticle powder without further chemical modification, or, via short-term pepsin digestion, into a self-assembling cardiac extracellular matrix hydrogel with preserved bioactivity.

Tissue-Engineered Grafts from Human Decellularized Extracellular Matrices: A Systematic Review and Future Perspectives

“…In the heart, the ECM is responsible of several pathophysiologic responses, including fibrosis, inflammation, angiogenesis, cardiomyocyte contractile function and viability, and resident progenitor cell fate [135]. For this reason, the importance of using tissue-specific matrix for generation of biological cardiac scaffolds is increasingly being acknowledged.…”

“…Human heart decellularization has been applied to whole organs [137,139,140,141] or cardiac muscle fragments [142] harvested from cadavers and unusable for clinical transplantation, as well as to tissue sections procured during surgical procedures (i.e., implantation of a mechanical assist device, heart transplantation, and resection of a subaortic outflow tract obstruction) [135,138,143,144,145,146,147,148]. Left ventricular biopsies derived from myocardial infarction patients were also processed [138].…”

“…Perfusion decellularization of whole human hearts via antegrade flow through the ascending aorta or coronary arteries was achieved by the use of both detergent (SDS) [137,139,140] and detergent–enzymatic (SDS, Triton X-100/DNase) solutions [141]. Myocardial sections were decellularized by employing the same ionic (SDS, deoxycholic acid, sodium deoxycholate) [135,137,138,139,140,141,142,143,144,145,146,147,148] and non-ionic detergents (Triton X-100) [138,148], with [135,141,142,143,144,145,146,147,148] or without [137,138,139,140,148] the addiction of enzyme treatment. Interestingly, other than direct endonuclease incubation, the intrinsic DNase activity of foetal bovine serum was experienced to eliminate residual DNA [135,138,143,144,148].…”

“…Similarly, decellularization protocols of heart slices allowed to obtain cell-free scaffolds preserved in both protein composition and tissue architecture [135,138,143,145,148]. Considering evaluation of mechanical properties, acellular myocardial sheets maintained the characteristics of a relaxed native tissue [145].…”

Towards a Novel Patch Material for Cardiac Applications: Tissue-Specific Extracellular Matrix Introduces Essential Key Features to Decellularized Amniotic Membrane

“…Human myocardium was harvested under sterile conditions and stored for no longer than 48 h at 4 °C before sectioning. Human Cardiac Extracellular Matrix (hcECM) isolation and processing was performed as described [ 45 ]. The myocardium was cut into cubes with an edge length of approximately 1 cm, embedded into Tissue Tec O.C.T (Sakura Inc., Alphen aan den Rijn, The Netherlands), sectioned in 300 µm thick slices using a CM 3050S cryostat (Leica, Wetzlar, Germany) , and stored at −80 °C before further processing.…”