CCR7基因修饰的未成熟树突状细胞在大鼠高危角膜移植免疫排斥反应中的作用

Effects of CCR7 gene modified immature dendritic cells in rat high-risk corneal transplantation rejection

目的研究趋化因子受体7(chemokine receptor 7,CCR7)基因重组腺病毒体外转染供体骨髓来源的未成熟树突状细胞(immature dendritic cells,imDC)对大鼠高危角膜移植免疫排斥反应的作用。方法以60只SD大鼠为受体,30只Wistar大鼠为供体,碱烧伤建立高危角膜移植模型。将SD大鼠分为空白对照组、未修饰imDC组、imDC+腺病毒空载体组(imDC+Ad组)和imDC+CCR7腺病毒组(imDCs+Ad-CCR7组),每组15只;各组受体术前7 d和术后3 d经尾静脉注入PBS液0.1 mL、供体来源的未修饰imDC 10×106个(0.1mL)、空载体腺病毒转染后的imDC 10×106个(0.1 mL)和携带CCR7腺病毒转染后的imDC 10×106个(0.1 mL);术后受体大鼠每天裂隙灯下观察角膜植片存活情况并对角膜植片的混浊、水肿及新生血管程度进行评分;术后14 d每组随机处死5只大鼠取角膜行HE切片观察。结果角膜植片存活时间:空白对照组(10.44±1.88)d,imDC组(16.00±2.18)d,imDC+Ad组(15.11±2.03)d,imDC+Ad-CCR7组(23.67±2.83)d,4组间比较差异有统计学意义(F=53.005,P=0.000);与空白对照组相比,imDC组、imDC+Ad组、imDC+Ad-CCR7组角膜植片存活时间均明显延长(均为P<0.01);imDC+Ad-CCR7组较imDC组与imDC+Ad组均明显延长(均为P<0.01)。角膜植片HE染色切片显示,imDC+AdCCR7组的植片轻度水肿、基质层板层纤维排列有序,未修饰imDC组和imDC+Ad组呈不同程度的水肿,基质层板层纤维排列轻度紊乱、有少量炎性细胞;空白对照组植片高度水肿、角膜基质板层纤维紊乱并出现大量炎性细胞和新生血管。结论静脉注入CCR7基因修饰的imDC可以明显延长大鼠高危角膜移植后角膜植片存活时间,抑制角膜移植免疫排斥反应。

Objective To investigate the effects of immune tolerance to rat high risk corneal transplantation rejection with chemokine receptor 7 （ CCR7 ） recombinant adenovirus in vitro transfection of donor bone marrow-derived immature dendritic cells （imDC）. Methods Thirty Wistar rats and sixty SD rats were respectively used as do nors and recipients, corneal neovascularization was induced by alkaline burn. The recipi ents were randomized into model control group, imDC group, adenovirus void vector transfected group （imDC ＋ Ad group） and CCR7 adenovirus transfected group （imDC ＋ Ad-CCR7 group） ,15 cases in each group. In the control group,SD rats were only injec ted 0.1 mL PBS via tail vein before operation. In the imDC group, donor bone marrow derived imDC of 10 x 106 were injected into SD rats via tail vein before operation. In the imDC ＋ Ad group, adenovirus void vector transfected donor bone marrow-derived imDC of 10 x 106 were injected into SD rats via tail vein before operation. In the imDC ＋ Ad CCR7 group, CCR7 adenovirns transfected donor bone marrow-derived imDC of 10 x 106 were injected into SD rats via taft vein before operation. Ocular anterior segment reac tion was examined under the slit lamp and corneal opacification, edema and neovascu larization were scored based on Larkin＇ s criteria. The graft survival time was calculat ed. In each group,five recipients were killed on the 14th day after transplantation, and the corneal grafts were stained by HE. isults The survival time of corneal grafts was （ 10.44 ± 1.88）days in control group, （ 16.00 ±2.18）days in imDC group, （ 15.11 ± 2.03） days in imDC ＋Ad group and （23.57 ±2.83） days in imDC ± Ad-CCR7 group,there were statistical differences （ F = 53. 005, P = 0. 000 ）. The mean survival time of imDC group,imDC ＋ Ad group and imDC ＋ Ad-CCR7 group were longer than that in control group, there were statistical differences（ all P 〈 0.01 ）. The survival time of imDC ＋ Ad CCR7 group was longer than those of imDC group and imDC ＋ Ad group, there were sta tistical differences（ all P 〈0.01 ）. But between imDC group and imDC ＋ Ad group,there was no statistical difference （P 〉 0.05 ）. The results of HE showed that the graft was slightly edema and the fiber in matrix layer was arranged orderly in im DC ＋ Ad-CCR7 group, which was edema in certain degree and arraxtged slight disorderly with few inflam matory cells in imDC group and imDC ＋ Ad group;The graft was highly edema,and the fi ber was arranged disorderly with many inflammatory cells and neovascularization in con trol group. Couclusion The imDC transfected with CCR7 recombinant adenovirus which injected into SD rats via tail vein can prolong the survival time of rat corneal graft after transplantation and inhibit the rejection of corneal transplantation.