Ex Vivo and In Vivo Analysis of a Novel Porcine Aortic Patch for Vascular Reconstruction

Abstract

(1) Background: The aim of the present study was the biocompatibility analysis of a novel xenogeneic vascular graft material (PAP) based on native collagen won from porcine aorta using the subcutaneous implantation model up to 120 days post implantationem. As a control, an already commercially available collagen-based vessel graft (XenoSure®) based on bovine pericardium was used. Another focus was to analyze the (ultra-) structure and the purification effort. (2) Methods: Established methodologies such as the histological material analysis and the conduct of the subcutaneous implantation model in Wistar rats were applied. Moreover, established methods combining histological, immunohistochemical, and histomorphometrical procedures were applied to analyze the tissue reactions to the vessel graft materials, including the induction of pro- and anti-inflammatory macrophages to test the immune response. (3) Results: The results showed that the PAP implants induced a special cellular infiltration and host tissue integration based on its three different parts based on the different layers of the donor tissue. Thereby, these material parts induced a vascularization pattern that branches to all parts of the graft and altogether a balanced immune tissue reaction in contrast to the control material. (4) Conclusions: PAP implants seemed to be advantageous in many aspects: (i) cellular infiltration and host tissue integration, (ii) vascularization pattern that branches to all parts of the graft, and (iii) balanced immune tissue reaction that can result in less scar tissue and enhanced integrative healing patterns. Moreover, the unique trans-implant vascularization can provide unprecedented anti-infection properties that can avoid material-related bacterial infections.

Vascular Remodeling of Clinically Used Patches and Decellularized Pericardial Matrices Recellularized with Autologous or Allogeneic Cells in a Porcine Carotid Artery Model

“…Stöwe et al [ 52 ] noted more favorable host tissue integration, a less pro-inflammatory reaction, and a more improved vascularization pattern of a novel acellular collagen material derived from a porcine aorta compared with XenoSure ® in a rat subcutaneous implantation model. Notably, they also observed cell debris in microscopic closeups of XenoSure ® .…”

Comparison of the Validity of Enzymatic and Immunohistochemical Detection of Tartrate-resistant Acid Phosphatase (TRAP) in the Context of Biocompatibility Analyses of Bone Substitutes

“…In contrast, BMGCs as inflammatory cells also exhibit a lytic activity. However, this cell type is degrading and resorbing foreign bodies including many biomaterials such as synthetic bone substitute materials (45,48,49). ii) Osteoclasts are involved in the tissue regeneration process via their well described crosstalk with osteoblasts in both physiological and pathological situations (47).…”

In VitroAnalysis of the Cytocompatibility of a Novel Porcine Aortic Patch for Vascular Reconstruction

“…Based on these structural differences, it is assumable that the two investigated grafts show distinct patterns of tissue integration and therefore, in their long-term outcome after transplantation. In fact, various tissue integration processes were observed in an initial in vivo study of the two biomaterials (41).…”

“…So far, no remarkable negative or cytotoxic effects are documented for its application. The mild inflammatory reactions post implantationem, as observed in the aforementioned in vivo study including the patch, seem to underline its sufficient biocompatibility (41). However, neither these in vivo investigations nor the current available clinical data to the material are suitable for sufficient long-term statements to the compatibility and degradation behaviour of the patch.…”

“…It can be assumed, that this cell-free biomaterial does not induce an exaggerated immune-mediated inflammatory response after implantation. An initial approval of this assumption was reached within the aforementioned in vivo investigation with a demonstrated mild inflammatory tissue response and no immune-modulated rejection of the graft (41). In the case of the XenoSure ® patch, on the other hand, several remaining cells of the bovine donor could be identified within the material (Figure 2B-C).…”