Experimental Study On Preventing Immune Rejection Of Allograft Tendon Transplantation On TP Compare With CsA

Objective: In the hand injury patients, the tendon injuries accounted for about 30%, tendon defects and need for line of the tendon transplant accounted for 25%. The traditional method of tendon defect is autologous tendon transplantation, which existence shortcomings of drawn limited and influence derived site function and others. Since the 1950s, launched a study of allogeneic transplant tendons for the treatment of tendon defect open a new road split; the resource of allograft tendon is adequate, easily obtained, short operative time, less pain , and little effect on the new injury and the donor function; but because of the immune rejection work not resolved, the project has not made a breakthrough. How to reduce the immune response of tendon allograft rejection after transplantation and the causing tendon adhesion problems has been been the biggest question of application.Tendon is the rules dense fibrous connective tissue,can be divided into collagen fibers,tendon,matrix and tendon cells,the tendon cells can secret matrix and collagen.Tendon is a less blood,less cells tissue,belongs to low-antigen-based tissue,the major components of antigenicity is histocompatibility antigens(HLA) mainly exist in tendon cells composition,of which the collagen fibers do not express significant antigenicity.How to effectively reduce tissue antigen, while maintaining tissue activity is the key-point.Allograft tendon exist immunogenicity.Both the tendon cells, matrix, collagen can induce immune responses.The purpose of tendon allgraft preparation is removal of immunogenicity and retains graft biomechanical properties.As the part of the allograft,the immunological mechanism of allogeneic tendon transplantation should follow allograft.Tendon transplantation also through the cellular and humoral immunity of graft. Celluar immune should occur in the earlty period of acute response, monocyte-based infiltration (mainly T cell) common in lesions.Methods:Choose four month old white Leghorn healthy 90 male chickens, with an average 2.1±0.053 Kg. Randomly divided into A, B and C three groups, each group has 30 chickens.Group A as triptolide, group B as cyclosporine A, group C as control group. This experiment choose Lenghorn chicken left footâ…¢,â…£toe as models. In the upper animals'thigh, the intramuscular injection of 1% ketamine(15mg/kg) and diazepam(1mg/kg), regular disinfection after anaesthesia, take the palm side of Bruner 's incision, cut the skin from the first interphalangeal joint to toes, approximately 4.0 cm length, and separate sharply along the plantar side of tendon sheath shallow, laterally turn up flap and expose the plantar side of tendon sheath, longitudinal cut along the median of tendon sheath to expose light flexor and deep tendon, trim about 1.5cm tendon in the middle of the two tendon tie of flexor deep tendon and interchange the three cutting tendons from A,B,C group.Three groups were sewed double "8" suture with 4-0 nylon no damage seam and in the surrounding 2-pin reinforcement. A group of patients: oral triptolide, 100ug/kg/day, after three weeks withdrawal.Group B: intramuscular injection of streptozotocin Green A, 10mg/kg/day, three-week withdrawal.Group C: no treatment.The experiment for tendon treatment three groups(1) the morphology histologic observation: morphological analysis respectively in general, HE dyeing and electron microscopy three aspects; (2) test the three group on maximum tensile strength of tendon ruptune and breaking adhesions power by using Css-44020 biomechanical testing machine.(3) Peripheral blood by flow cytometry CD₄⁺.CD₈⁺T lymphocyte counts detect and calculate the CD₄ ⁺/CD₈ ⁺ ratio.The experimental animal model of tendon injury through the preparation, which were treated with triptolide and cyclosporin A after allogeneic tendon transplantation; to observe the form of histology,biomechanics,and peripheral blood CD₄⁺, CD₈⁺ T lymphocyte counts detect and calculate the CD₄⁺/CD₈⁺ ratio,to analysis the inhibitory effect of immune response mechanisms and for the preparation of allogeneic tendon to provide a new method.Results:(1)morphology histologic observation:â‘ generally: group A good healing, smooth surface, most of it express a little film adhesion, even no adhesions;Group B tendon heal well and smooth surface, surrounding of tendon has less adhesion;Group C tendon healed, surface is not smooth, surrounding of tendon express heavy adhesion.â‘¡HE dyed: group A tendon inner of anastomosis orderly arrangement of collagen fibers, more same as the normal tendon tissue, cross silce shows the orderly arrangement of collagen fibers, tendon surface smooth, no adhesion with the surrounding or no mild filiform adhesion;Group B tendon anastomotic collagen fibers arranged orderly, same as normal tendon tissue,crosscut slice show collagen fibres were rules,smooth surface, tendons surrounding no adhesion or mild filamentous adhesion; group C tendons anastomotic collagen fibres converge unanimous, cross slice visible section collagen fibres were not whole, poor healing, surface not smooth, more tendon adhesion.â‘¢Transmission electron microscope: group A the cytoplasm of fiber cells exit a large number of pool like rough endoplasmic reticulum, cavity filled with secretion; Fibroblast, nuclear large, euchromatin rich and heterochromatin less; A large number of collagen fibers, arranged in neat and compact. B group new collagen fibers and more disordered; Fibroblasts, abundant rough endoplasmic reticulum, cysts to expand into a pool-like sharp, large, cavity filled with protein synthesis; fibroblasts and a large number of fibroblasts, a large number of collagen fibers arranged in neat rows. Group C of fibroblasts, the cytoplasm of a small amount of rough endoplasmic reticulum, slight expansion of cysts, containing a small amount of protein synthesis; less collagen fibers; collagen fibers Medium arranged, irregularly. (3) biomechanical testing: Three weeks: the maximum tensile strength tendon(Pmax): except group A between B, any two group overall mean difference was statistically significant; Breaking adhesions power(W₀):among A, B, C the three groups overall mean difference was statistically significant. Six weeks: the maximum tensile strength tendon (Pmax):among A, B, C the three groups overall mean difference was statistically significant; Breaking adhesions power(W0): except group A between B, any two group overall mean difference was statistically significant. Comprehensive two aspects test results that between Group A and B biomechanical tendons no significant differences, among of Group A, B and C there were significant differences.(3) Peripheral CD₄⁺, CD₈⁺ T lymphocyte count detection: Three weeks: CD₄⁺ T peripheral blood lymphocyte count, among of A, B, C three groups overall mean differences were statistically significant; Peripheral blood CD₈⁺ T lymphocyte count and CD₄⁺ / CD₈⁺ ratio, except group A between B, any two group overall mean difference was statistically significant; Six weeks: CD₄⁺ T peripheral blood lymphocyte count, among of A, B, C three groups overall mean differences were statistically significant; Peripheral blood CD₈⁺ T lymphocyte count and CD₄⁺ / CD₈⁺ ratio, except group A between B, any two group overall mean difference was statistically significant; Explaining that Note the use of oral triptolide A and intramuscular injection of cyclosporine method to reduce the immunogenicity of the tendon and the immune rejection.Conclusion:Same as cyclosporin A, triptolide has anti-immune rejection, allograft treatment of triptolide, cyclosporin A can be more fully remove tendon immunogenicity and no affection on extracellular matrix and collagen fiber, no changement of biomechanical properties.Almost completely eliminate the immunogenicity of allograft tendon, offers a new approach to the tendon allograft transplantation.