Du D, Chang S, Chen B, Zhou H, Chen Z K
Institute of Organ Transplantation, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
Transplant Proc. 2007 Dec;39(10):3446-8. doi: 10.1016/j.transproceed.2007.03.114.
Heme oxygenase-1 (HO-1) has been implicated in graft protection because its induction is associated with long-surviving allografts. The aim of this study was to analyze the efficacy of adenovirus-mediated HO-1 overexpression to inhibit graft arteriosclerosis and estimate whether the protective role correlated with nuclear factor kappaB (NF=kappaB) expression and grafts apoptosis.
Aortic transplantation was performed using inbred Brown-Norway (BN) rats (RT1n male) as donors and Lewis rats (RT1l male) as recipients. The experiments were divided into four groups: group A, Lewis-Lewis (n=6), no treatment; group B, BN-Lewis (n=6), no treatment; group C, BN-Lewis (n=6), donor aorta perfused with buffer containing 4x10(10) pfu Ad-Null (the noncoding adenoviral vector); and group D, BN-Lewis (n=6), donor aorta perfused with buffer containing 4x10(10) pfu Ad-HO-1 (adenoviral vector coding for HO-1). All grafts were harvested at 60 days after transplantation. Reverse transcriptase polymerase chain reaction was performed to detect the expression of HO-1 gene. Hematoxylin and eosin staining was used to detect the morphology and cytology of the transplanted vessels. Intimal thickening was detected by Masson staining. Immunohistochemistry was used to detect the localization and expression of HO-1 and NF-kappaB and TUNEL assays to detect the apoptosis of the grafts.
Gene transfer of HO-1 grafts using an adenoviral vector resulted in the expression of HO-1 protein in endothelium and adventitia. We observed that the intimal thickness in Ad-HO-1-treated aortas (11.11+/-0.92 microm) was significantly thinner compared with untreated (85.20+/-6.90 microm) or Ad-null treated (87.20+/-6.20 microm) aortas (P<.01). Immunohistology showed that treatment with Ad-HO-1 resulted in a significant reduction in leukocyte infiltration and a decreased number of vascular smooth muscle cells in the intima, compared with Ad-null-treated aortas. The levels of NF-kappaB and the number of apoptotic cells in Ad-HO-1-treated aortas showed significantly lower compared with Ad-null-treated arotas (P<.05).
HO-1 prevented the development of graft arteriosclerosis in the rat aortic transplant model. The protective role of HO-1 in chronic rejection lesions seemed to correlate with downregulation of the expression of NF-kappaB and inhibition of apoptosis in the grafts.
血红素加氧酶-1（HO-1）与移植物保护有关，因为其诱导与长期存活的同种异体移植物相关。本研究的目的是分析腺病毒介导的HO-1过表达抑制移植物动脉硬化的效果，并评估这种保护作用是否与核因子κB（NF-κB）表达及移植物凋亡相关。
采用近交系棕色挪威（BN）大鼠（RT1n雄性）作为供体、Lewis大鼠（RT1l雄性）作为受体进行主动脉移植。实验分为四组：A组，Lewis-Lewis（n = 6），未治疗；B组，BN-Lewis（n = 6），未治疗；C组，BN-Lewis（n = 6），用含4×10¹⁰ pfu腺病毒空载体（非编码腺病毒载体）的缓冲液灌注供体主动脉；D组，BN-Lewis（n = 6），用含4×10¹⁰ pfu腺病毒HO-1（编码HO-1的腺病毒载体）的缓冲液灌注供体主动脉。所有移植物在移植后60天收获。进行逆转录聚合酶链反应以检测HO-1基因的表达。苏木精-伊红染色用于检测移植血管的形态和细胞学。用Masson染色检测内膜增厚情况。免疫组织化学用于检测HO-1和NF-κB的定位及表达，TUNEL检测用于检测移植物的凋亡情况。
使用腺病毒载体对HO-1移植物进行基因转移导致HO-1蛋白在内皮和外膜表达。我们观察到，与未处理（85.20±6.90微米）或腺病毒空载体处理（87.20±6.20微米）的主动脉相比，腺病毒HO-1处理的主动脉内膜厚度（11.11±0.92微米）明显更薄（P<0.01）。免疫组织学显示，与腺病毒空载体处理的主动脉相比，腺病毒HO-1处理导致白细胞浸润显著减少，内膜中血管平滑肌细胞数量减少。与腺病毒空载体处理的主动脉相比，腺病毒HO-1处理的主动脉中NF-κB水平和凋亡细胞数量显著降低（P<0.05）。
HO-1可预防大鼠主动脉移植模型中移植物动脉硬化的发展。HO-1在慢性排斥病变中的保护作用似乎与NF-κB表达下调及移植物凋亡抑制相关。
