Mesothelial morphology and organisation after peritoneal treatment with solid and liquid adhesion barriers–a scanning electron microscopical study

Abstract

Separation of traumatized tissue represents the only promising strategy in postoperative adhesion prevention, a relevant clinical problem after surgical intervention. In the present study scanning electron microscopy (SEM) and subsequent morphometry were used to analyse the tissue response to five commercial adhesion barriers. Standardised peritoneal lesions in Wistar rats were covered with solid and viscous barrier materials and semiquantitatively analysed 14 days postoperatively. Striking morphological differences in lesion surface organisation between the barrier groups became apparent with colonisation of the barrier by mesothelial cells to different degrees. Furthermore, the mesothelial cells showed either a normal or activated phenotype depending on the underlying biomaterial. These experiments demonstrate that the examination by SEM gives useful insights into the performance of barrier materials and the cellular processes of adhesion prevention, since mesothelial cells play an active role in the pathogenesis of adhesion formation.

Tissue response to five commercially available peritoneal adhesion barriers—A systematic histological evaluation

“…The implementation of pharmacological substances would transform the concept of solely using physically separating barriers into a material-assisted tissue regeneration by use of highly optimized and functionalized biomaterial systems in the true sense of tissue engineering. 1,4 Besides fibrosis, the foreign body reaction is crucially regulated by macrophages and might be differently influenced by various biomaterials. Regarding the results of this study, it is interesting that there was a negative minimum of the barrier value in the evaluation of granulocytes in the groups treated with Adept and Intercoat.…”

“…In support of this hypothesis, SupraSeal was associated with the best adhesion-preventing effect and highest degree of remesothelialization in a scanning electron microscopical study. 1,4 However, to clarify the interplay of inflammation and fibrosis in peritoneal wound healing on the one hand and the influence of barrier materials on these mechanisms on the other, further histological and immunohistochemical studies are necessary. In this context an important limitation of this study have to be seen in the fact, that although a large range of relevant barriers are clinically applied, our study represents only a selection of available materials.…”

“…Besides the clinical symptoms of the patients, the treatment of peritoneal adhesions affects significantly the social system causing costs up to US $1.3 billion per year in the United States alone. 1 Peritoneal adhesion formation is a result of a complex cascade, which is not yet completely understood. However, it is known that a variety of cellular and humoral factors, including mesothelial cells and cytokines are involved.…”

“…In the prevention of peritoneal adhesions, SupraSeal has shown promising results. 1,4,18,19 Even if several barrier materials are already in clinical use and well documented by experimental and clinical studies, the optimal barrier material has not yet been found. Therefore, it is essential to improve our knowledge about the cellular reaction to the different materials on adhesion formation.…”

Combined intraoperative administration of a histone deacetylase inhibitor and a neurokinin-1 receptor antagonist synergistically reduces intra-abdominal adhesion formation in a rat model

“…18,31–33 Numerous studies have firmly established that peritoneal fibrinolysis is compromised after surgery, either by a reduction in tPA or an increase in its principal inhibitor, plasminogen activator inhibitor-1, 34 or both, indicating that peritoneal fibrin accumulation and stabilization is a key underlying event early in adhesiogenesis. 18,31,32,35 Although our previous studies showed that augmenting the peritoneal fibrinolytic system reduced adhesion formation in a rat model, 14–16,19 the coadministration of any of these compounds did not increase adhesion prevention, owing in part, to their mechanistic similarities.…”