Immunohistochemical analysis of the Effect of Plasma Enriched Platelets (PRP) Coating in Polypropylene Mesh Integration on Vaginal Mucosa in a Rabbit Model

Abstract

Despite high success rates in the treatment of urinary incontinence, complications related to the use of polypropylene mesh can not be neglected. Many innovations have been studied recently aiming to improve mesh's integration. In this fiel, the platelet-rich plasma (PRP) has been used effectively in many areas of Medicine, improving wound repair, related to a high concentration of growth factors. Considering the PRP properties on the physiological processes related to tissue repair, we propose to coating the monofilament polypropylene mesh with a PRP gel in order to allow better integration into the tissues. The aim of this study is to evaluate, using immunohistochemical techniques, the effect of PRP in the integration of monofilament polypropylene meshes implanted in the vaginal wall of rabbits, studying the immunoinflammatory response, the collagen's metabolism and angiogenesis. The samples of this study are derived from a previous study perfomed by one of the researchers of our group, in which 30 adult female White New Zealand rabbits were submitted to the polypropylene monofilament mesh implantation in the vaginal wall. In 15 of them, mesh was complexed with platelet-rich plasma in the form of gel. The rabbits were subdivided into 3 groups of 10 rabbits (5 with and 5 without PRP), and euthanized at 7, 30 and 90 days after surgery for extracting the vagina. It will be used specific reagents to demonstrate the immunohistochemical expression of the following aspects of interest: (a) immunoinflammatory response, evaluated by proinflammatory agents (interleukin 1 - IL-1 and tumor necrosis factor receptor - TNF alpha) and anti-inflammatory agents (TGF-beta and interleukin 13 - IL-13); (B) collagen metabolism (Matrix metalloproteinase 2 and 3 - MMP-2 and 3); (C) angiogenesis (CD-31). The percentage area and the average density of immunoreactive for each of the selected reagents will be measure by AxioVision image analysis program Microscope V 4.8.0.0 ® (Karl Zeiss, Germany), except for the CD-31, for which the evaluation will be made by counting the number of blood vessels in the field. Statistical analysis will be performed with the Kruskal-Wallis test for comparison between periods and the Wilcoxon test for comparison between groups. To compare the measurements between periods and groups will be used ANOVA. The significance level will be 5% (P <0.05). We hope to better understand the process of tissue integration of prostheses combined with platelet-rich plasma aiming future applicability in pelvic reconstructive surgery. (AU)