Altered structural and mechanical properties in decellularized rabbit carotid arteries

Abstract

Recently, major achievements in creating decellularized whole tissue scaffolds have drawn considerable attention to decellularization as a promising approach for tissue engineering. Decellularized tissues are expected to have mechanical strength and structure similar to the native tissues from which they are derived. However, numerous studies have shown that mechanical properties change after decellularization. Often, tissue structure is observed by histology and electron microscopy, but the structural alterations that may have occurred are not always evident. Here, a variety of techniques were used to investigate changes in tissue structure and relate them to altered mechanical behavior in decellularized rabbit carotid arteries. Histology and scanning electrom microscopy revealed that major extracellular matrix components were preserved and fibers appeared intact, although collagen appeared looser and less crimped after decellularization. Transmission electrom microscopy confirmed the presence of proteoglycans (PG), but there was decreased PG density and increased spacing between collagen fibrils. Mechanical testing and opening angle measurements showed that decellularized arteries had significantly increased stiffness, decreased extensibility and decreased residual stress compared with native arteries. Small-angle light scattering revealed that fibers had increased mobility and that structural integrity was compromised in decellularized arteries. Taken together, these studies revealed structural alterations that could be related to changes in mechanical properties. Further studies are warranted to determine the specific effects of different decellularization methods on the structure and performance of decellularized arteries used as vascular grafts.

Decellularized bovine reinforced vessels for small-diameter tissue-engineered vascular grafts

“…This behavior can be ascribed to the presence of more abundant muscular components in the 1st and 2nd DEM cycle with respect to the two successive DEM cycles and to the resulting un-crimped collagen structure, as histologically observed. Referring to this latter point, it has been previously reported that decellularized rabbit carotid arteries were stiffer than native vessels, being probably related to the presence of un-crimped collagen in decellularized arteries (18). Therefore, it is possible to infer that both these conditions (i.e.…”

“…The DEM approach has been proven as an effective method to obtain ECM-derived prosthetic grafts, which can support in vitro and in vivo cell adhesion and proliferation: acellular matrices are remodelled in living tissues and can function as urethra (13), small bowel (14), skeletal muscle (15), esophagus (16) and tracheal (17) substitutes. However, while many studies focused on the decellularized tissue biocompatibility, cell seeding and implantation potential, only few reported findings on relationships between tissue decellularization and the physical and mechanical properties of tissue (7,18).…”

Experimental investigation of collagen waviness and orientation in the arterial adventitia using confocal laser scanning microscopy

“…The two main features, characterizing collagen fiber organization, are its waviness and angular dispersion. Other factors that could determine the mechanical properties of the adventitia are collagen cross-linking, fiber density and glycoproteins (Williams et al 2009;Et-Taouil et al 2001).…”

Comparison of Three Methods for the Derivation of a Biologic Scaffold Composed of Adipose Tissue Extracellular Matrix

“…11,[14][15][16][17][18][19][20][21][22][23][24] When tissues have been efficiently decellularized, the ECM-specific structural and functional components that remain (collagen, laminin, fibronectin, growth factors, etc.) are relatively well conserved across mammalian species and, therefore, do not evoke adverse immune reaction.…”