| Objective A new three-dimensional scaffold was prepared by electrospun gelatin/polycaprolactone(GT/PCL)nanofiber aerogels(NFAs)combined with cartilage extracellular matrix(ECM),and its role in rabbit cartilage injury models was studied.Methods Firstly,the GT / PCL electrospun membrane was prepared by electrospinning and was ground into the short fiber at high speed.ECM was extracted and separate from fresh bovine articular cartilage,which mixed with the short fiber solution(10:1).Subsequently,it was used to prepared GT/PCL/ECM three-dimensional scaffold.Finally,detecting the physical characteristics of the three different scaffolds(GT / PCL,ECM and GT / PCL / ECM),including the composition,microstructure,swelling rate,porosity,compressive strength and degradation rates.And the biocompatibility research was getting on by co-culturing the scaffold with chondrocytes.Thirty male New Zealand white rabbits were selected according to the random number table and divided into two time points of 3 weeks(15)and 6 weeks(15).Rabbits were divided into a blank group(n=5)and an ECM group(n=5),the composite stent(GT/PCL/ECM)group(n=5)according to the random number table,in each time point.Establishing an injury model and implanting three types of bio-scaffold materials into different groups.At 3 weeks,6weeks,the three groups of animals were evaluated by the semi quantitative global MRI scoring system(WORMS);after the animals were killed,the knee joints of each group were observed and scored by the international society for cartilage repair histological score(ICRs);the cartilage repair was observed by HE staining and safranine green staining,and the ICRs histological score was performed.Results The three scaffolds showed a porous three-dimensional structure under the scanning electron microscope,FIRT showed that GT and PCL have been introduced into the scaffolds;GT/PCL NAF was loose and unable to be characterized by materials science.The swelling rate of GT/PCL/ECM [(1 092.0±32.2)%] is higher than that of ECM [(933.6±16.3)%](P<0.01);GT/PCL/ECM porosity [(92.3±2.3)%] higher than ECM [(85.9±2.2)%](P<0.05);the compressive strength of ECM scaffold [(2.7±0.1)k Pa] and the compressive strength of GT/PCL/ECAM scaffold [(2.4±0.1)k Pa],the difference was not statistically significant(P>0.05);the degradation rate of ECM scaffold was higher than that of GT/ PCL/ECAM scaffold the difference was not statistically significant(P>0.05);The cytotoxicity rating of GT/PCL/ECM scaffold was grade I,which indicated that its biocompatibility is better.At 3 weeks,the MRI WORMS score of the GT/PCL/ECM group was [(49.00 ± 11.40)points] compared with the ECM group[(40.00 ± 6.70)points] and the blank control group [(24.00 ± 6.51)points] significantly higher(P <0.05);the general ICRS score of GT/PCL/ECM group was(7.40±1.14)points,which was significantly higher than that of ECM group [(4.60±1.14)points] and blank control group [(3.00±1.22)points](P <0.01);ICRS histological score GT/PCL/ECM group and ECM group were(6.80±0.83)points and(4.20±0.83)points respectively compared with the blank control group [(2.80±0.83)points] were significantly higher(P<0.05);At 6 weeks,the MRI WORMS score of the GT/PCL/ECM group was [(86.00±4.18)points] compared with the ECM group [(67.00±9.74)points] and the blank control group [(43.00±7.58)points] significantly higher(P<0.05);the general ICRS score GT/PCL/ECM group is(14.00±0.70)points,which is higher than the ECM group [(11.20±1.64)points] and the blank control group [(5.60±1.67)points] Significantly higher(P<0.01);ICRS histological score GT/PCL/ECM group and ECM group were(16.80±1.92)points and(10.80±0.83)points respectively compared with the blank control group [(7.00±0.70)points],there is a significant increase(P<0.05).Conclusion GT/PCL/ECM composite scaffold has similar tissue structure to natural cartilage,and is superior to traditional ECM scaffold in physical properties and biocompatibility.It provides a stable environment for chondrocyte adhesion and growth,promotes collagen regeneration,and thus accelerates the repair of cartilage injury. |
PDF Full Text Request