他克莫司对移植免疫反应中核因子κB活性和淋巴细胞趋化因子表达的影响

Tacrolimus inhibits NF-κB activity and lymphotactin gene expression after heart transplantation in mouse

目的研究他克莫司(FK506)对移植免疫反应中细胞核因子κB(NF-κB)活性和淋巴细胞趋化因子(Lptn)表达的影响。方法应用小鼠同种心脏移植急性排斥反应模型,分为BALB/c-BALB/c同基因对照组、C57BL/6-BALB/c异基因对照组、C57BL/6-BALB/c移植+FK506处理组。RT-PCR检测移植心组织内Lptn mRNA的表达,凝胶电泳迁移率和ELISA分别检测心脏移植小鼠脾细胞NF-κB的活性和活化T细胞核因子(NFAT)c1活性。结果同基因移植组各时间点移植心内无Lptn mRNA表达;异基因移植组和FK506处理组移植后第1天和第3天均无Lptn mRNA表达,而第5天和第7天均可检测到Lptn mRNA阳性表达,但FK506组Lptn mRNA表达受抑制。治疗剂量的FK506可以明显抑制脾细胞NF-κB和NFATc1的活性,但FK506处理组心脏移植后第5、7天脾细胞NF-κB的活性仍明显高于同基因移植组。NF-κB活性与Lptn基因转录水平呈正相关关系(r=0.775,P=0.000)。结论 FK506除了通过抑制NFATc1活性途径调控部分Lptn mRNA的表达,还可通过抑制NF-κB途径参与Lptn mRNA表达的调控。

Objective To investigate the effect of tacrolimus（FKA06） on NF-κB activity and lymphotactin （Lptn） gene transcription in murine cardiac transplantation. Methods A fully major histocompatibility complex incompatible C57 BL/6 （ H- 2b） - to- BALB/c （ H- 2d ） murine cardiac transplantation model was used for in vivo studies. All mice were randomly divided into BALB/c-to-BALB/c isograft group, C57BL/6-to-BALB/e allograft group, and allograft ＋ FK506 group. Histopathological changes of graft specimens were examined at indicated time. Reverse transcription PCR was used to determine the mRNA expression of Lptn in cardiac grafts. NF-κB （p65/p50） and NFATcl activity of splenocytes after transplantation was assessed by the enzyme-linked immunoabsorbent assay. NF-κB activity was also identified by the electrophoretic mobility shift assay. Results Lptn mRNA was undetectable in cardiac isografts. Lptn mRNA transcription which was undetectable on day 1 and day 3 was upregulated in acutely rejecting cardiac allografis on postoperative day 5 and clay 7, and this upregulation was partially inhibited by FKS06. NFATc1 activity in splenocytes which was markedly upregulated during acute rejection was completely inhibited by FKS06 given intraperitoneally at a close of 1 mg · kg^-1· d^-1, while NF-κB （P65/ P50）activity on day postoperative 5 and day 7 was still higher than that in the isografts. A positive correlation was found between NF-κB （P65/P50）activity and Lptn mRNA expression（ r = 0.775, P = 0. 000）.Conclusion FK506 may play a role in the regulation of Lptn mRNA expression by completely inhibiting NFATcl activity and partially blocking NF- κ（P65/P50） activity.