Characterization of Extracellular Matrix Derived From Porcine Organs Decellularized Using Different Methods

Abstract

Regenerative medicine has extended the capacity of medicine to a point where tissues and organs could potentially be manufactured. This could resolve issues associated with organ transplantation. The extracellular matrix (ECM) provides a supportive scaffold and biochemical cues allowing cells to attach, proliferate, and differentiate. The ECM is composed of different fibrous proteins and proteoglycans. The extensive value of ECM lies in its dynamic microenvironment that aids in cell proliferation, differentiation, and regulation of intercellular communication. In this study, four methods were applied to decellularize porcine organs. The ECMs were characterized by histological methods illustrating the absence of nuclei and the presence of glycosaminoglycans (GAGs) and collagen. Hematoxylin and eosin analysis of native pancreas revealed necrosis by auto-digestion, also supported by a reduced dsDNA content, and could have led to the destruction of Type IV collagen, laminins, and other proteins in the resulting ECMs, as confirmed by mass spectrometry. DNA quantification of ECM revealed residual dsDNA contents lower than those of the native organs. Bicinchoninic acid (BCA) assay showed a difference in protein content between organs. Mass spectrometry coupled with proteomic analysis highlighted a significant difference in the protein composition. The number of different proteins, in some cases with more than 2700, in the produced ECM depended on the applied decellularization technique. Polarization microscopy indicated differences in the orientation of collagen fibers. This study provides a multimodal approach to characterize ECMs produced using different decellularization techniques, aiding in finding a balance between maintaining the ultrastructure and composition of ECM, while removing cellular components.