A Critical Evaluation of the Impact of Decellularization Processes on Bovine Pericardium

Francis E. Smit, Leana Laker, Hans Vand den Heever, Leselle Botes

University of the Free State, Bloemfontein, South African Republic

Date, time and location: 2018.05.25 10:30, Exhibition area, 1st Floor. Zone – D

Abstract

Objectives:

Decellularized bovine pericardium patches or tissue scaffolds have been developed by several groups in an attempt to attenuate the immune response to xenograft implants, thereby delaying calcification and tissue degeneration. The purpose of this study was to critically evaluate the impact of the Frater decellularisation  process, an SDS and detergent based process, on bovine pericardium during in vitro and in vivo studies.

Methods:

A propriety decellularization and sterilization process using SDS and other detergents was evaluated for efficiency and impact on tissue integrity. Decellularisation was confirmed using microscopy and DNA extraction. Tensile strength and Youngs modulus and elctronmicroscopic structural assessment were performed. Collagen, denatured collagen, elastin and GAG content was compared between fresh and decellularised pericardium. Triglyseraide content was measured as well alpha Gal concentrations. Calcium content was evaluated in explanted decellularised tissue after 8 week implantation in rats and compared to gluteraldehyde fixed tissue, gluteraldehyde fixed and detoxified tissue, and a combination of decellularisation and fixation/detoxification tissue.

Results:

Tensile strength and Youngs modulus were reduced by decellularization process but did not reach statistical significance. There were also moderate reductions in collagen, denatured collagen and elastin content, but a significant reduction in GAG content. A moderate reduction in alpha Gal occurred from 13,52 to 11,86 /mg of fresh tissue. Triglycerides were significantly reduced from 1mg/g to 0.08mg/g tissue.

Calcium content was significantly reduced in explants after decellularization  compared to other groups.

Discussion:

SDS combination decellularization processes is associated with a non significant tissue strength reduction , a pronounced reduction in GAG’s and triglyceride content and an insignificant reduction in alpha Gal. Decellularisation is associated with marked reduction in calcification compared to any group using gluteraldehyde.