The cartilage tissue regeneration- biosignalized gelatin with EGF on tissue scaffold with controlled release of RHBMP7

Title: The Cartilage Tissue Regeneration- Biosignalized Gelatin with EGF on Tissue Scaffold with Controlled Release of rhBMP7 Researcher Name, Faculty and Correspondence address: BILGEHAN ILKER Dokuz Eylul University Faculty of Medicine, Plastic and Reconstructive Surgery Department İnciraltı –İzmir Aim and hypothesis: Cartilage defects can be caused congenital or acquired from trauma, tumor resection. Thus defects leads to functional and aesthetic problems; cartilage tissue because of its avascular structure has a very limited capacity for self repair. Cartilage tissue engineering studies are still under discussion by using different cell sources, tissue scaffolds and variety of biosignals molecules. Despite invitro with its cell-polymer studies reported successful results ofen with adult chondrocytes and stem-cells groups can not be applied in clinical practice because of its difficulties to obtain sufficient cells and high cost problems. In this study as an animal experiment is used rabbit. In its ears will be created cartilage defects and try to perform (biosignalized with EGF gelatin tissue scaffold) release of rhBMP7 control on a new tissue scaffold. It is aimed to create ready biomaterials which can be used in clinical practice, increase the capacity of cartilage tissue regeneration by dual growth factors of perichondrial progenitor cells effects without the needs of additional cell source. It is aimed to create ready biomaterials which can be used in clinical practice, increase the capacity of cartilage tissue regeneration by dual growth factors of perichondrial progenitor cells effects without the nees of additional cell source Materials and Methods: In this study 18 New Zelland Rabbits (age ranging 1-1,5 years; weight ranging 2,5-3,5 kg) were used. Subjects were divided into 5 groups. In the 1st Group; Only 1x1 cm resection was sutured on the rabbits ear cartillage structure. On the 2nd group its also created the same magnitude defect of cartilage structure and put into as a plain form the bİosignalized with EGFR gelatin tissue scaffolds. In Group 3 it was placed in roll form. In 4th and 5th group it was placed microspheres in a prepared tissue scaffold which will control the release of rhBMP7 and rhBMP7 were immobilized. Prepared rhBMP7 which will controll the release was placed in defects on group 4 in plain form and group 5 in roll form. The suitability of the prepared tissue scaffold in case of the study was verified by making morphological and mechanical analyses. At the end of the 8 weeks waiting period animals were sacrificed and histochemical and immunohistochemical tests were done. Results were graded according to Ulutas and Modified Pineda Histological Scoring System and compared with statistical analysis. Results: When histomorphological and immunohistochemistry results were compared, it was intense observed hypertrophy and ossification in the control group, and it was seen a repair on the cartilage tissue scaffold characteristics esspecially in group 4 and all others where biosignalized with EGFR gelatin tissue scaffold provided release control of rhBMP7. Group 2 and group 4 which tissue scaffold layer were engrafting flatly, consisted tissue was lining all defect zone, group 3 and group 5 which tissue scaffold layer were engrafting rooled shape, chondrogenesis shapes similar scaffold conformation and observed that central of defect didn't demonstrated new repair tissue. Whether EGF molecule signly using scaffold compaire with rhBMP 7 dualling using groups deffect repletion ratio between cartilage transition zone properties significant difference, cell morphology between matrix coloration didn't encountered synergistic effect. Conclusion: By biosignalized with EGFR and controlled release of rhBMP7 gelatin sponge structured tissue scaffold and effects of pericondrial progenitor cells the cartilage regeneration capacity increase and this study can be a lightway for being used in cartilage tissue engeneering. Thus it stands far from disadvantages of cell-polymer system and it is considered as an example study for producing a low cost implant in clinical application. The scaffold can be formed using three -dimensional structure will be used for all kinds of benefits for cartilage defects. Keywords: scaffold, greater depth of penetration, cartilage regeneration, rhBMP 7, EGFR dual growth factor, cartilage tissue engineering