Natural Scaffolds for Regenerative Medicine: Direct Determination of Detergents Entrapped in Decellularized Heart Valves

Abstract

The increasing urgency for replacement of pathological heart valves is a major stimulus for research on alternatives to glutaraldehyde-treated grafts. New xenogeneic acellular heart valve substitutes that can be repopulated by host cells are currently under investigation. Anionic surfactants, including bile acids, have been widely used to eliminate the resident cell components chiefly responsible for the immunogenicity of the tissue, even if detergent toxicity might present limitations to the survival and/or functional expression of the repopulating cells. To date, the determination of residual detergent has been carried out almost exclusively on the washings following cell removal procedures. Here, a novel HPLC-based procedure is proposed for the direct quantification of detergent (cholate, deoxycholate, and taurodeoxycholate) residues entrapped in the scaffold of decellularized porcine aortic and pulmonary valves. The method was demonstrated to be sensitive, reproducible, and extendable to different types of detergent. This assessment also revealed that cell-depleted heart valve scaffolds prepared according to procedures currently considered for clinical use might contain significant amount of surfactant.

Limitations of recellularized biological scaffolds for human transplantation

“…Consequently, a more comprehensive and exhaustive evaluation of acellular scaffolds is needed to ensure reproducibility, efficacy of cell removal, and maintenance of ECM integrity. To address these shortcomings, new techniques have been developed to test the mechanical properties of the scaffold (Den Hondt et al, ) and to measure the amount of decellularization reagents remaining after decellularization (Dettin et al, ). Knowledge of the critical micelle concentration of detergents (Stetsenko & Guskov, ) should aid in the development of standardized decellularization solutions that prevent micelle formation and thereby the risk of deleterious protein extraction.…”

Different approaches to heart valve decellularization: A comprehensive overview of the past 30 years

“…The bile acid/salts have a strong cytotoxic effect, and their use in conjunction with non-ionic detergents has recently demonstrated a more efficient removal of their residues from the ECM, providing an environment more receptive to cell recolonization. 80 The ECM can unfortunately also express xenogeneic elements that are species-specific, responsible for the onset of a state of local inflammation and calcium site nucleation. Historically, quantification of cells and/or DNA residues in a xenogeneic tissue has been adopted as a measure of effectiveness in removing antigen content; however, cells or nucleic materials do not necessarily correlate with residual xenogeneic debris.…”

“…Based on the author's experience, the best choice that allows excellent decellularization results, good matrix preservation, and cell renewal potential is the sequential use of biliary salts at low concentrations (better if conjugated) with non‐ionic detergents (such as Triton X‐100). The bile acid/salts have a strong cytotoxic effect, and their use in conjunction with non‐ionic detergents has recently demonstrated a more efficient removal of their residues from the ECM, providing an environment more receptive to cell recolonization …”

Label-free assessment of carotid artery biochemical composition using fiber-based fluorescence lifetime imaging

“…Cryopreservation and chemical processing of tissue engineered vascular grafts derived from both human and animal tissues are currently used in clinical applications of vascular repair [ 29 – 31 ]. The absolute fluorescence lifetime values of elastin and collagen vary significantly depending on sample preparation, storage, and environment, and the fluorescence lifetime values of elastin and collagen solutions differ from those in native tissue [ 32 – 34 ].…”