The Effect Of T Lymphocyte On The Repairment Of Firearm Sciatic Nerve's Disrupted Injury

Background: The successful regeneration of the firearm peripheral nerve's disrupted injury is still a problem to be solved. Recently the study on Neuro-immuno-endocrinology showed that the specific T lymphocytes induced by the injury of the peripheral nerves had potent potential in improving the nerve regenerative microenvironment. This would provide a bright future in improving the nerve regeneration after firearm peripheral nerve's disrupted injury through regulating T lymphocyte's function. To make this idea come true, the animal models of immune-tolerance and that of immune-enhancement to the autoantigen in the sciatic nerve were established. Then the roles of the T lymphocytes on the repairment of the sciatic nerve's incised injury were illustrated. Finally the results were applied to enhance the regeneration of the firearm sciatic nerve's disrupted injury. The study consisted of three parts:Part I The establishment of the animal models1. To establish the immune-tolerance model of the New Zealand rabbits: (1)The sciatic nerve emulsion(SNE) was made by using the sciatic nerve homegenate (SNH)from adult New Zealand rabbits and incomplete Freund's adjuvant(IFA).(2)To inoculate the neonatal rabbits with 0.1ml/mg SNE after birth and at 3 months old. Then sciatic nerve's incised injury were made at 5 months old. The following parameters were measured:Ⅰ.Levels of T lymphocyte's activation: ①Ratio of CD4+/CD8+. ②Level of CD25. ③Proliferative level of T lymphocytes. ④Proliferative level of T lymphocytes stimulated by PHA. ⑤Level of T lymphocytes in the injured sciatic nerve. Ⅱ. The development of the rabbits.The results showed that the immune-tolerance models to the autoantigens in the sciatic nerve of the New Zealand rabbits were successfully established. 2. To establish the immune-enhancement model of the New Zealand rabbits: To inoculate the adult NewZealand rabbits subcutaneously in the tails with 0.1ml/mg SNE 1 week before the sciatic nerve's incised injury. The following parameters were measured : Ⅰ.The levels of the T lymphocyte's activation. Ⅱ.The pathological changes in the injected sites of the tails. The results indicated that the immune-enhancement model to the autoantigens in the sciatic nerve of the New Zealand rabbits can be established.3. To establish the firearm sciatic nerve's disrupted injury model of the New Zealand rabbits: 0.37g triangle fragments driven with different doses of gunpowder were fired by 53-type musket to the midpoint of the surface projection of the sciatic nerve in New Zealand rabbits. The following parameters were measured: flying characters of the fragments, energy absorption, disruptive rates of nerve,infectious rates, and the mortality. The results showed that the animal model of firearm sciatic nerve's disrupted injury model could be successfully established by a 0.37g triangle fragment at velocity of 541.4±26.5m/s driven by 0.30g gunpowder when the shot-distance is 1.5m.Part Ⅱ The effect of T lymphocyte on the regeneration of sciatic nerve's incised injury1.The effect of T lymphocytes on the nerve regenerative microenvironment after sciatic nerve's incised injury: T lymphocyte induced by the sciatic nerve's incised injury can improve the regenerative microenvironment: ①It can express NGF (Nerve growth factor) and BNDF(Brain-derived neurotrophic factor) by themselves;②It can increase the levels of NGF and BDNF in the injuried nerve; ③It can strengthern the macrophages' ability of chemotaxis and eliminating the degenerative myelin; ④It can enhance the proliferative ability of schwann cells .2.The roles of T lymphocytes on the nerve regeneration after sciatic nerve incised injury: T lymphocytes can remarkably enhance the rerve regeneration, including: (1) It can ensure more neurons alive through increasing the level of NTFs; (2)It can improve the quality of the regenerative axon; (3) It can strengthen the target organs to restore their functions.Part Ⅲ The effect of T lymphocytes on the repairment o...