An in vitro and in vivo study on the intensity of adhesion and colonization by Staphylococcus epidermidis and Pseudomonas aeruginosa on originally synthesized biomaterials with different chemical composition and modified surfaces and their effect on expression of TNF-α, β-defensin 2 and IL-10 in tissues

The aim of this study was to determine adhesion and colonization of bacteria on the surface of originally synthesized glass-ceramic biomaterials and their effect on inflammation reactions in tissues surrounding the implant. Materials and Methods: Biomaterial discs were contaminated with bacterial suspensions of 10, 10², and 10³ colony forming units (CFU)/mL (P. aeruginosa ATCC 27853 and S. epidermidis ATCC 12228), and after 2 hours of cultivation, the intensity of bacterial adhesion was determined. For in vivo tests, the samples were contaminated with 10², and 10³ CFU/mL cultivated at 37°C for 2 h to ensure bacterial adhesion. Contaminated biomaterial samples were implanted in the interscapular area of chinchilla rabbits for 2 and 4 weeks. The biomaterials were removed, and using plate count and sonification methods, bacterial colonization on the surface of biomaterials was determined. Moreover, the expression of TNF-α, β-defensin 2, and IL-10 in the surrounding tissues was assessed by using immunohistochemistry methods. Results: P. aeruginosa more intensively colonized biomaterials in the in vivo study as compared with S. epidermidis. Il-10 is a regulatory cytokine, which reduces the intensity of inflammatory cell activity, thus reducing nonspecific resistance of the organism. Conclusions: The expression of TNF-α and IL-10 was not affected by short (2 and 4 weeks) biomaterial implantation. Pronounced cytokine expression in tissues around implanted biomaterials contaminated with P. aeruginosa was observed.