Abstract: Abstract: Objective To construct a biomimetic degradable fiber scaffold with polycaprolactone (PCL) and poly lactic-co-glycolic acid (PLGA) as raw materials, and to evaluate its feasibility as a tissue engineering annulus fibrosus (AF) scaffold. Methods The PCL-PLGA hybrid scaffold was prepared by melt spinning method using PCL and PLGA mixture as the experimental group. The pure PCL scaffold was used as the control group. The microstructure (fiber diameter and pore diameter) of the finished scaffold was observed by scanning electron microscopy (SEM), and the porosity was measured. The elastic modulus of the scaffold was measured using a mechanical loading device. The degradation of the scaffold was monitored in vitro. The biocompatibility of the scaffold was detected by CCK-8 method and cell Live /dead staining after seeding Human Wharton’s jelly-derived mesenchymal stem cells (HWJ-MSCs). Results There were no significant differences in fiber diameter, pore size and porosity between the experimental group and the control group under SEM (P＞ 0.05). The orientation of the scaffold fiber was good under the microscope, and the fiber angle was 60° . The compression elastic modulus of the hybrid scaffold was (1.42 ± 0.11) MPa, and tensile elastic modulus was (5.47 ± 0.23) MPa. The compressive elastic modulus of the pure PCL scaffold was (2.36±0.19) MPa, and tensile elastic modulus was (8.95±0.22) MPa. The results of in vitro degradation assay indicated that the degradation cycle of the hybrid scaffold was compatible with proliferative capacity and activity on the scaffold. Conclusion The PCL-PLGA fiber scaffold prepared by melt spinning method can simulate the natural AF microstructure, which has biodegradability, good biocompatibility and mechanical properties. It is a suitable scaffold carrier for constructing tissue engineering intervertebral disc. the self-repair process of the annulus fibrosus. CCK-8 assay and Live / dead staining showed that HWJ-MSCs had good

Key words: tissue engineering, mesenchymal stem cells, annulus fibrosus, biodegradation, PCL, PLGA