Vascularization of Novel Porcine Acellular Dermal Matrix

Abstract

The aims of this study were to observe the growth of vascular endothelial cells (VECs) and the vascularization of novel porcine acellular dermal matrix (PADM), and to investigate the methods for modifying heterologous dermal substitutes in order to improve their compatibility. Twenty-four Wistar rats were divided into a PADM group and a HADM group, which were transplanted with PADM and HADM, respectively. At the 3rd day, and at the 1st, 2nd, and 4th week after the operation, the dermal substitute was removed, and HE staining and CD34 and factor VIII immunohistochemical staining were performed. The distribution and proliferation of VEC, the vascularization, and histological changes in the dermal substitute were observed. At the 3rd postoperative day, tiny capillaries sprouted in the dermal substitute and began to proliferate. At the 1st postoperative week, the new capillaries extended into the dermal substitute. At the 2nd postoperative week, the new capillaries had entered the dermal substitute and further increased in number, and were more mature than the capillaries in the 1 st postoperative week (P<0.05). At the 4th postoperative week, the capillaries were distributed everywhere in the dermal substitute, along with further matured VECs, but the capillary number was not significantly increased compared with the 2nd postoperative week (P> 0.05). There was a good VEC proliferation in implanted PADM, with immigrated fibroblasts and matured capillaries. The novel PADM showed good tissue compatibility.

Evaluation of alginate dialdehyde as a suitable crosslinker on modifying porcine acellular dermal matrix: The aggregation of collagenous fibers

“…Hence, PADM is often chemical or physical modified to adjust its physicochemical properties, especially the enzymatic degradation rate to meet the clinical requirements, with the methods of UV‐light irradiation, dehydrathermal treatment (DHT), and synthetic crosslinking reagents (carbodiimide (EDC), glutaraldehyde (GA), and polyepoxy compound) . However, the UV‐light irradiation treatment confines to the surface modification of PADM, the treatment by DHT makes little contribution to the physicochemical property of PADM and the cytotoxic nature of synthetic crosslinking agents i.e., EDC, GA, and polyepoxy compound reflected in the process of modifying PADM may prohibit their utilization in the field of tissue engineering . To overcome the aforementioned cytotoxic effect of synthetic crosslinking agents and the low efficacy of physical crosslinking treatments, a natural derived crosslinker, alginate dialdehyde (ADA) was developed in our previous work …”

“…[1][2][3] As a biological scaffold, PADM is obviously biocompatible and not only provide mechanical support serving as an ideal threedimensional (3D) architecture for host cells to grow and metabolize, but also facilitate cell-scaffold interactions, which actively influence cellular responses, for instance, cell proliferation, and differentiation. 4,5 Accordingly, PADM has been extensively applied as substrates for skin repairing, as implants for breast shaping, and as scaffolds for dura matter, bone, and soft connective tissue remodeling. 3,6 Despite many of the superiorities of PADM as sketched above, the relatively weak enzymeresistance property of PADM may limit its use as biological scaffolds which need to be faced up to.…”

“…1,2 However, the UV-light irradiation treatment confines to the surface modification of PADM, the treatment by DHT makes little contribution to the physicochemical property of PADM and the cytotoxic nature of synthetic crosslinking agents i.e., EDC, GA, and polyepoxy compound reflected in the process of modifying PADM may prohibit their utilization in the field of tissue engineering. 4 To overcome the aforementioned cytotoxic effect of synthetic crosslinking agents and the low efficacy of physical crosslinking treatments, a natural derived crosslinker, alginate dialdehyde (ADA) was developed in our previous work. 7 Alginate (ALG), ubiquitously found in brown algae, is a biocompatible, nonimmunogenic, and biodegradable natural negatively charged polysaccharide, of which the typical structure is a block copolymer consists of two sterically different repeating units, (1,4)-linked b-D-mannuronic acid (M) and a-L-guluronic acid (G) monomers.…”

“…4 To overcome the aforementioned cytotoxic effect of synthetic crosslinking agents and the low efficacy of physical crosslinking treatments, a natural derived crosslinker, alginate dialdehyde (ADA) was developed in our previous work. 7 Alginate (ALG), ubiquitously found in brown algae, is a biocompatible, nonimmunogenic, and biodegradable natural negatively charged polysaccharide, of which the typical structure is a block copolymer consists of two sterically different repeating units, (1,4)-linked b-D-mannuronic acid (M) and a-L-guluronic acid (G) monomers. [8][9][10][11][12] It is worthy to note that ALG could be oxidized to form a natural derived crosslinker (alginate dialdehyde, ADA) with multiple functional aldehyde groups, of which the active group could react with the free amino groups the same as glutaraldehyde.…”

“…Recently, porcine acellular dermal matrix (PADM), which is mainly composed of type I collagen has gained the most attention of researchers in the field of tissue engineering and regeneration due to its excellent biological achievements . As a biological scaffold, PADM is obviously biocompatible and not only provide mechanical support serving as an ideal three‐dimensional (3D) architecture for host cells to grow and metabolize, but also facilitate cell‐scaffold interactions, which actively influence cellular responses, for instance, cell proliferation, and differentiation . Accordingly, PADM has been extensively applied as substrates for skin repairing, as implants for breast shaping, and as scaffolds for dura matter, bone, and soft connective tissue remodeling .…”