CD40靶向小干扰RNA抑制大鼠异体肢体移植急性排斥反应后细胞凋亡及P53、P21表达

目的探讨CD40靶向小干扰RNA（即短发夹RNA，shRNA）对大鼠异体肢体移植急性排斥反应及细胞凋亡的影响。方法以纯系SD大鼠为供体，纯系Wistar大鼠为受体，行同种异体右后肢移植。27只大鼠肢体移植后随机分为3组：实验组．注射梭华一Sofast（15μl）-siCD40—2，pSilencer（100μg）载体复合物600μl；空载体对照组，在肢体移植后，即注射Sofast（15μl）-pSilencer4．1-CMVneo（100μg）空载体复合物600μl；生理盐水对照组，在肢体移植注射生理盐水600μl。观察移植物排斥反应征象及存活情况，并于第7天对产生免疫耐受大鼠进行混合淋巴细胞反应（MLR），同时进行组织学检查。结果与其他组相比．实验组移植物发生排斥反应的时间及存活时间均显著延长（P〈0．01）（〉13d），未见排斥反应征象，其他组均于术后近期发生排斥反应；实验组大鼠对供体的淋巴细胞呈现低反应性，移植的供体同系大鼠的肢体得以存活。实验组移植物细胞凋亡率低于其他组。结论在术后不应用免疫抑制剂的情况下，CD40靶向的shRNA干扰可以抗大鼠异体肢体移植急性排斥反应。

Resistance to acute rejection and apoptosis in limbs allotransplantation of rats by RNA interference of CD40 costimulatory molecule

Objective To study the effect on resistance to acute rejection of composite tissue allotransplantation by using method of expression of CD40 costimula/ory molecule on rat lymphocytes inhibited by short hairpin RNA （sbRNA）. Methods The inbred SD rats were chosen as donors and inbred Wistar rats as recipients. Twenty-seven recipients were divided into 3 groups randomly after allogeneic leg transplantation. Rats in experimental group were injected Sofast （15 μl）-siCD40-2/pSilencer 600 μl the day after transplantation; carrier control group rats received Sofast （15 μl） -pSilencer 4.1 -CMV neo （100 μg） 600 μl the day after transplantation;In normel salt solution group,injected of sodium chloride 600 μl the day after transplantation. The condition of survival and rejection of grafts were observed. Rats which still survived 7 days after operation were received the mixed lymphocyte reaction （MLR）. Results Compared 3 groups,mean survival time of limb allografts was prolonged obviously in experimental group （P 〈 0.01 ）. Rejection of grafts was never observed. Rejection of grafts was all emerged during short term after transplantation in the other groups. Rats in experimental group had a low reaction to the donors＇ lymphocyte. The expression of apoptosis in experiemental group was lower than other groups. Conclusion Without any immunosuppressants after the operation,the method of using RNA interference of CD40 costimulatory molecule can resist acute rejection in limb allotransplantation in rats.