New experimental approach to study host tissue response to surgical mesh materials in vivo

Abstract

Implantation of surgical meshes is a common procedure to increase abdominal wall stability in hernia repair. To improve biocompatibility of the implants, sophisticated in vivo animal models are needed to study inflammation and incorporation of biomaterials. Herein, we have established a new model that allows for the quantitative analysis of host tissue response and vascular ingrowth into surgical mesh materials in vivo. Ultrapro meshes were implanted into dorsal skinfold chambers of Syrian golden hamsters. Angiogenesis, microhemodynamics, microvascular permeability, and leukocyte-endothelial cell interaction of the host tissue were analyzed in response to material implantation over a 2-week period using intravital fluorescence microscopy. Mesh implantation resulted in a short-term activation of leukocytes, reflected by leukocyte accumulation and adherence in postcapillary venules. This cellular inflammatory response was accompanied by an increase of macromolecular leakage, indicating loss of integrity of venular endothelial cells. Angiogenesis started at day 3 after implantation by protrusion of capillary sprouts, originating from the host microvasculature. Until day 10, these sprouts interconnected with each other to form a new microvascular network. At day 14, the inflammatory response had disappeared and the vascular ingrowth was completed. Histology confirmed the formation of granulation tissue with adequate incorporation of the mesh filaments within the host tissue. We conclude that this novel model of surgical mesh implantation is a useful experimental approach to analyze host tissue response and vascular ingrowth of newly devised materials for hernia repair.

Evaluation of the ability of collagen–glycosaminoglycan scaffolds with or without mesenchymal stem cells to heal bone defects in Wistar rats

“…In particular, inflammation induced initially after scaffold implantation has been linked with unsuccessful engraftment of tissue-engineering constructs [30][31]. A foreign body reaction to the implanted MSC-seeded scaffold may have resulted in premature scaffold degradation [32].…”

The dorsal skinfold chamber: window into the dynamic interaction of biomaterials with their surrounding host tissue

“…Accordingly, one major challenge in modern hernia repair is the development of novel surgical mesh materials, which exhibit an optimal biocompatibility and which are adequately integrated into the surrounding host tissue. For these reasons, the dorsal skinfold chamber has been introduced as a model, which allows for the fi rst time the repetitive in vivo analysis of infl ammatory effects, vascularisation and incorporation of different surgical mesh materials (Laschke et al, 2005a). Prolene ® , Ultrapro ® and Vicryl ® meshes are commonly used meshes, which differ in polymer composition, mesh architecture and resorbability.…”

“…In the following, this review will focus on the dorsal skinfold chamber model. By means of intravital fl uorescence microscopy, this chronic model has been broadly used during the last two decades for the repetitive in vivo analysis of various biomaterials and, thus, has provided deep insights into the mechanisms regulating the angiogenic and infl ammatory host tissue response to implanted biomaterials (Menger et al, 1990a;Kraft et al, 2000;Laschke et al, 2005a;Rücker et al, 2006;Laschke et al, 2007;Wieghaus et al, 2008). …”

Abdominal Wall Reconstruction in a Trauma Setting

“…New Prosthetics (Vypro, Proceed, and Sepramesh) [32,33] Advantages: good ingrowth of tissues, able to tolerate excess abdominal pressures and physiological compatibility. These have been in use for only a few years and still require long-term follow-up.…”