DEVELOPMENT OF IKVAV MODIFIED PLLA GUIDE TUBE HAVING UNIDIRECTIONAL FIBERS ON INNER SURFACE TO ENHANCE AXONAL EXTENSION

摘要

The bi-layer poly-L-lactic acid (PLLA) guide tube for peripheral nerve regeneration was developed by electrospinning method to enhance axonal extension. The inner layer of the guide tube had unidirectional nanofiber and Ile-Lys-Val-Ala-Val (IKVAV) modified surface. IKVAV modified unidirectional fiber sheets which had different fiber diameters from 400 to 1200 nm were fabricated to optimize fiber diameter of the guide tube for axonal extension. Fiber sheets without the IKVAV were prepared as the control group. PC12 cells seeded on the fiber sheets were cultured for 6 days. Axons were most extended in fiber diameter of 1090 nm with IKVAV and 1160 nm without IKVAV. Maximum axon length increased by about 25% due to IKVAV modification. The bi-layer guide tube which had fiber diameter about 1133 nm was fabricated. It was confirmed that the inner layer had unidirectional fibers and the outer layer had random fibers in the guide tube. CS, which corresponds to radial compressive stiffness, of the guide tube and the sciatic nerve were 230 N/mm~2 and 1.64 N/mm~2 respectively. Since radial compressive stiffness of the guide tube was higher than that of the sciatic nerve, the developed guide tube was expected to enhance axonal extension without narrowing.