ENHANCING MACROPHAGE BEHAVIOR SURROUNDING AMINO ACID COATED UHMW-PE IMPLANTED SUBCUTANEOUSLY

摘要

Polyethylene materials used in orthopedic applications are biocompatible and non-immunogenic with host tissues. The purpose of this investigation was to determine macrophage behavior after implantation of ultra-high molecular weight polyethylene (UHMW-PE) rinsed with saline (control) or coated with poly-L-lysine (PLL), arginine-glycine-aspartic acid (RGD), or arginine-glycine-glutamic acid (RGE) into 16 adult male rats subcutaneously (S/C). Implants and surrounding tissue were harvested at 90 days post-implantation. The animals were euthanized, and the UHMW-PE implants and the fibrous tissue capsules surrounding them were harvested. Microscopic examination of routinely stained sections (5 microns, Hematoxylin & Eosin) of the fibrous tissue capsules revealed macrophage counts were highest in the PLL coated group (3.13±0.79 cells/high power field). There was a decrease in mean macrophage counts per high power field in the RGD coated group (1.58±1.02), saline (1.32±0.46), and RGE (0.92±0.76) coated groups compared to PLL. There were statistically significant differences (ANOVA, p < 0.05) of all three experimental groups compared to control. These findings indicate macrophage behavior at the tissue-implant interface and in surrounding fibrous tissue can be influenced using various amino acid combination coatings in subcutaneous applications. These results provide further evidence that the intensity of the chronic inflammatory reaction to UHMW-PE can be manipulated to some extent by simple amino acid coatings that may enhance biocompatibility.