Objective To investigate the influence of collagen on the biomechanics strength of tissue engineering tendon. Methods All of 75 nude mice were madethe defect models of calcaneous tendons, and were divided into 5 groups randomly. Five different materials including human hair, carbon fibre (CF), polyglycolic acid (PGA), human hair and PGA, and CF and PGA with exogenous collagen were cocultured with exogenous tenocytes to construct the tissue engineering tendons.These tendons were implanted to repair defect of calcaneous tendons of right hind limb in nude mice as experimental groups, while the materials without collagenwere implanted to repair the contralateral calcaneous tendons as control groups. In the 2nd, 4th, 6th, 8th and 12th weeks after implantation, the biomechanicalcharacteristics of the tissue engineering tendon was measured, meanwhile, the changes of the biomechanics strength were observed and compared. Results From the 2nd week to the 4th week after implantation, the experimental groups were ber than the control groups in biomechanics, there was statistically significantdifference (Plt;0.05). From the 6th to 12th weeks, there was no statisticallysignificant difference between the experiment and control groups (Pgt;0.05). Positivecorrelation existed between time and intensity, there was statistically significant difference (Plt;0.05). The strength of materials was good in human hair,followed by CF, and PGA was poor. Conclusion Exogenous collagen can enhance the mechanics strength of tissue engineering tendon, and is of a certain effect on affected limb rehabilitation in early repair stages.
Objective To investigate the possibility of repairing defected tendon with a tissue engineering tendon, combined culture of allogenous tenocyte and derived tendon. Methods Macaca tenocytes labelled by BrdU were seeded on the derived tendon. The flexor digitorum profundus of five fingers of left hand in 15 Macaca mulatta were resected and made 2.5cm defects as experimental model. They were divided into three groups according to repair methods (Group A: Combined culture of derived tendon materials and alloggenous tendon cells; Group B; Derived tendon materials; Group C; Autograft). In different stages, the labeled BrdU of tendon cells were observed. Results In Groupo A, after iin vivo implantation, the tenocytes could proliferate and synthesize collagen; the new tissue was white and glossy and the collagen fibers fused to form dense tendon structure as several weeks passed. Twelve weeks after implantation, the tenocytes still survived and synthesized collagen, the results of labelled cells were positive by immunothistochemical methods. By scanning electron microscopic observation, the tenocytes arraged regularly and evely among the derived tendon; the collagen fibers formed a network and its main direction was accord with that of the derived tendon. Normal nucleus, nucleolus, and cell organelles were seen under transmission electron microscope. Conclusion Combined culture of tenocytes with derived tendon is able to make tendon like tissue. The structure of tissue engineering tendon in similar to that of normal tendon.
This paper reviewed the main achievements in the research on tissue engineering tendon, focusing on major problems concerning the substitute for extracellular matrix (ECM) of tendon, biological characteristics of tendon cells, and tendon cells compounding with ECM substitute. It was concluded the important problems in the study of the tissue engineering having specific reparative functions could be: to prepare the ECM materials suitable for the tendon cells to attach, grow, and function; to establish the tendon cell line whose growth, proliferation, and immunological antigenicity could be modulated and controlled, and simulating the mechanical environment of tendon in vivo, to adopt three-dimensional tendon cell culture method.