Study On The Osteogenic Effect Of PMMA Bone Cement Modified With Lactoferrin

Objective:Polymethyl methacrylate bone cement(PMMA bone cement)is a commonly used filling material in orthopedic surgery.Its good and stable performances make it the most widely used in all kinds of bone cement.In view of the disadvantage that PMMA bone cement has no biological activity,scholars have made a lot of attemps.We try modify the Lactoferrin(LF)onto the surface of PMMA bone cement to construct LF/PMMA bone cement to promote bone regeneration.Method:LF was modified on the surface of PMMA bone cement by strong ultraviolet irradiation and chemical cross-lingking.SEM,FT-IR and EDS were used to characterize the surface of the samples.It was verified that LF was successfully modified on the surface of PMMA bone cement.The osteogenic potential of LF/ PMMA bone cement in vitro was evaluated by co-culture with MC3T3-E1 cells,and PMMA bone cement was used as control group.SEM and DAPI staining were used to detect the effect of surface modification on the adhension and extension of MC3T3-E1cells;CCK-8 assay was used to detect the effect of surface modification on the proliferation of MC3T3-E1 cells;ALP activity and extracellular matrix mineralization were used to detect the effect of surface modification on the effect of early and late differentiation of MC3T3-E1 cells.Results:We were able to modify LF on the surface of PMMA bone cement,and SEM results showed that the microstructure of PMMA bone cement surface does not change significantly after LF modification.The results of FT-IR and EDS verify that LF has been successfully modified on the surface of PMMA bone cement.The results of SEM for 24 hours showed that mouse preosteoblasts MC3T3-E1 could adhere and extend well on the surface of bone cement.The results of CCK8 on the first,third,fifith day showed that the number of cell proliferation in LF/PMMA bone cement group was significantly higher than in PMMA bone cement group(P<0.05),and on the seventh day SEM results showed that LF/PMMA bone cement group produced a large amount of extacellular matrix,which was significantly better than that in PMMA bone cement group.The results of ALP activity showed that ALP activity in LF/PMMA bone cement group was significantly higher than that in PMMA bone cement group on the 7th and 14 th day(P<0.05),and the results of extra cellular matrix mineralization test showed that compared with PMMA bone cement,LF/PMMA bone cement group could produce red stained calcium noduled with darker color and larger area(P<0.05).Conclusions:(1)LF can be successfully modified on the surface of PMMA bone cement by phsical/chemical mixed modification.(2)LF/PMMA bone cement can significantly promote the adhension,proliferation,alkaline phosphatase activity and extracellular matrix mineralization of MC3T3-E1 cells.