Heterogeneous Experimental Study Of Biological Bone Screw

Heterogeneous biological experimental study of bone nailObjective: to observe the animal experiments of biological bone screw hole in the body of outcome, and compared with absorbable screws an autologous cortical bone screwsin the biological outcome, biomechanical properties, and immunogenicity response differences, evaluation of such disinfection and the merits of antigen process, evaluation is the biological properties of cortical bone screws. Provide a theoretical basis for clinical application.Methods: 6 adult goats in China, was made of the left hind femur condyle of the transverse double condyle fracture, medial condyle of the crown with 2.5mm * 15mm Hao cancellous bone screw fixation, external condyle measured with the same specifications can be absorbed clinical cancellous bone screw, fracture fixation observed the effect of intraoperative and postoperative 12 weeks, 24 weeks, 36 weeks, 48 weeks X-ray examination, 36 weeks after surgery, 48 weeks histopathological observation, observation of double Measuring prognosis and screw fracture healing situations; to 18 healthy adult goats (including long-term observation group 6), into bone screw interface Hao crown group, sterilization and disinfection of sheep bones bone interference screw interference screw group, at all set of experiments run wild goats hind femoral condyle screw placement interface, a, in the double hind tibial interference screw implantation in the one run wild. Respectively after 12 weeks and 24 weeks of trial sheep were sacrificed 3, femur bone screw interface, the Department of Pathology, observation, observation of the interface inflammation of bone screws, bone screws absorption alterations and changes in the surrounding cancellous bone. The histological score for Lane; test the initial interface stress load, and the rows of mechanical test specimens, test indicators, including the maximum interface stress load, compression stiffness. The numerical results obtained above experiment was analyzed with SPSS13.0.RESULTS: The test with sheep operation I have healed. Imaging Observation of long-term observation group: After 12 weeks, 24 weeks, femoral condyle fracture line disappeared, see a lot of callus growth and shoot Hao shadow blur around the screw, nail shape can be seen; after 36 weeks, the fracture shaping completed crown Hao screw shadow blur; 48 weeks after surgery, bone screws in the region are still higher than the surrounding bone tissue density. Histological observation: After 36 weeks: bone screw to the visible part of the cortical bone component, combined with the surrounding bone trabeculae close. Absorption of nails: cancellous bone implants absorption seen in inflammatory empty residual; after 48 weeks: bone screw: The bone marrow cavity shows cortical bone screws, bone nails organization of Haversian canal clearly visible. Absorbable screw: inflammatory hole still exists. Interface nail histopathological observation group: 12 weeks: Hao interface screw crown group of local no inflammatory cell infiltration, destruction of bone screw, bone snail column shows osteoclasts; sterilized bone shows a large number of inflammatory cells nail group infiltration, fiber cover obvious; disinfection sheep bones nails see inflammatory cell infiltration, fiber cover weaker than sterilized bone screws, local infiltration of osteoclasts seen; after 24 weeks: Hao Guan bone interface, screw thread completely absorbed damage group , bone nail and bone around the sharp bone of the host connection; sterilized bone nail group fiber cover obvious osteoclasts little; disinfection sheep bones nails see a little inflammatory cell infiltration, local shows infiltration of osteoclasts, bone formation of connections ; Lane histological score after each set of data for statistical analysis, P <0.01. Shows significant differences among the groups, the highest Hao nail group> disinfection sheep bones nail group> disinfection bone nail group. Biomechanical testing: the initial interface stiffness load line and squeeze stiffness, bone nail and the crown Hao interface between the two groups of disinfection of nail, P> 0.05 no significant difference; 12 weeks, P <0.05, there are differences, the highest Hao nail group> two groups of disinfection nail group, disinfection nail was no significant difference between groups; 24 weeks, P <0.01, significantly different, crown Hao nail group> disinfection sheep bones nail group> disinfection bone nail group. Help with time to engraftment, crown Hao biomechanical properties of bone screw further enhanced. The numerical results of the above experiment results were statistically analyzed with SPSS13.0. Conclusion: After long-term observation of biological bone screw can play a bone screw fracture. Toxic side effects, does not cause immune rejection, the body can be absorbed slowly; biological initial mechanical properties of bone screws of not less than fresh bone, and can longer maintain a stable mechanical properties; biological bone screw into a certain bone effects, combined with the host bone tissue, resulting in greater biomechanical properties.Heterogeneous bio-based evaluation of the immunogenicity of bone screwsObjective: To study the effect in human peripheral blood lymphocytes were cultured with bone material circumstances, the preliminary study lymphocyte activation and proliferation in vitro changes in the level, further analysis of the immunogenicity of xenogeneic bone material and its trigger immune possible responses.Methods: A total number of healthy blood, centrifugal separation, washed, lymphocytes were made of people. CCK-8 assay nail material effect on the lymphocyte proliferation after incubation with taking on the culture plate in the microplate reader measured the absorbance 450nm and 650nm. CFSE staining combined with flow cytometry analysis of bone material on lymphocyte proliferation, cells cultured for 3 days to obtain cells, the machine testing, CFSE for the fluorescence 1 channel (FL1); data by FACSCalibur flow cytometry and CELLQuest software acquisition and analysis; flow cytometry analysis of bone material in vitro activation of lymphocytes were cultured on the machine detection, FITC as fluorescence 1 channel (FL1), PE for the fluorescence 2 channel (FL2); data by FACSCalibur flow cytometry and CELLQuest acquisition and analysis software. Results: CCK-8 was detected nail material on lymphocyte proliferation, achieved statistical software measurement data analysis and comparison with SPSS13.0 each experimental group and control group, the mean hydroxyapatite differences, found that different measurement nail material level of co-cultured lymphocyte proliferation compared with hydroxyapatite no significant difference (P> 0.05), while co-culture with fresh bone materials, the level of lymphocyte proliferation was significantly higher than that of hydroxyapatite ( P <0.05); flow cytometry analysis of bone material in vitro activation of lymphocytes, the results showed that hydroxyapatite group of lymphocyte proliferation index was 1.02±0.01, only the emergence of a parent peak, peak proliferation without offspring , does not appear reduced CFSE fluorescence intensity of different concentrations (0.5g/mL, 1g/mL, 2g/mL) of bone material had a progeny group cells peak shape, but very low proliferation index were 1.04±0.03 , 1.03±0.02,1.05±0.02, compared with hydroxyapatite was no significant difference (P> 0.05); CFSE staining combined with flow cytometry analysis of bone material on lymphocyte proliferation showed that bone screw material In vitro and heterologous immune cells were cultured in the case, heterologous immune cells did not affect transformation, can be inferred nail material with the immunogenicity is very low. Hydroxyapatite-negative group and cultured lymphocytes of its low rate of CD69 expression, indicating that T cells is still in the resting state; with different concentrations (0.5g/mL, 1g/mL, 2g/mL) of bone material activation in cultured cells, compared with the negative group had no significant difference; the bone with fresh cultured lymphocytes of their significantly increased the expression of CD69.Conclusion: Antigen processing by the highest Hao Bone nail material than the immunogenicity of untreated fresh bone. Guan Hao biological companies to antigen processing method is effective.