ABSTRACTIn this work, polylactic acid/polycaprolactone/silk fibroin (PLA/PCL/SF) nanofiber scaffolds with different mass ratios were prepared by electrospinning technology. The morphology and structure of the nanofiber scaffold were characterized with the scanning electron
microscope (SEM), and its porosity and adsorption were tested using the Fourier transform infrared spectrometer (FTIR). 24 New Zealand white rabbits were rolled into control group (n = 8, with autologous tendons) and experimental group (n = 16) randomly. The PLA/PCL/SF nanofiber
scaffolds were adopted to wrap autologous tendons to establish extra-articular models. Tendon-bone healing was evaluated six weeks after surgery through histological and biomechanical tests, and the related gene expressions in tissue cells were detected. It turned out that mass ratio of PLA/PCL
and SF components had a considerable impact on the morphology of the nanofiber scaffold. The surface of nanofiber with a mass ratio of 3:1 was distributed with dense pores. As the content of SF increased, the porosity and adsorption of the nanofiber scaffold gradually decreased. Moreover,
the experimental results suggested that the addition of SF improved the hydrophilicity of PLA/PCL/SF scaffold, which was beneficial to the adhesion and proliferation of NIH/3T3 (a mouse embryonic fibroblast cell line established by the National Institutes of Health (NIH)). In addition, histological
observation results showed that the width of the tendon-bone interface (TBI) of rabbits in control group was still relatively large at the 6th week after the surgery, with poor healing effect and disordered collagen arrangement. The widths of the TBI of the material group and rehabilitation
group were substantially narrower relative to that in control group, and the collagen was arranged regularly. It was suggested that the healing effects between tendon and bone in material group and rehabilitation group were accelerated, and the effect in the rehabilitation group was superior
to that of material group, indicating that rehabilitation exercise could organize the negative effects of training in postoperative rehabilitation training and promote the healing between tendons and bones.
Gas foaming of electrospun poly(L-lactide-co-caprolactone)/silk fibroin nanofiber scaffolds to promote cellular infiltration and tissue regeneration
