阻断Th17细胞分化对小鼠肠道急性移植物抗宿主病的影响

Blockage of Th17 cells differentiation exacerbated mouse acute intestine graft-versus-host disease fol- lowing allogeneic bone marrow transplantation

目的观察阻断Th17细胞分化对小鼠小肠急性移植物抗宿主病（aGVHD）的影响。方法将小鼠分为5组：正常对照组、单纯照射组、异基因骨髓移植（allo—BMT）组、allo—BMT＋二甲基亚砜（DMSO）组、allo—BMT＋常山酮（HF）组。移植后观察小鼠GVHD发生情况并进行临床和病理评分；移植后第14天（＋14d），用流式细胞术检测外周血Thl、Th17比例及IFN-γ和IL-17A浓度变化；＋14d，用RT—PCR方法检测小肠T—bet、ROR-T、CXCL9、CXCL10、CXCL11和CCL20转录因子表达水平。结果＋14d，allo—BMT＋HF组小鼠小肠损伤较重；allo—BMT＋HF组Thl细胞比例高于allo—BMT组[分别为（9．34±0．67）％和（6．69±1．37）％]，Th17细胞明显下降[分别为（0．46±0．04）％和（1．叭±0．04）％]（P〈0．05），allo—BMT组IL-17A和IFN-γ浓度分别为（3．54±0．06）和（41．67-4-0．11）ng／L，而allo—BMT＋HF组IFN一1浓度为（38．77．4-0．17）ng／L（P〈0．05），未检测到IL-17A。RT—PCR分析结果显示allo—BMT＋HF组小鼠小肠组织中RORTT表达均较allo—BMT＋BMT和正常对照组低（P〈0．01）；allo—BMT和allo—BMT＋HF组T-bet表达量均较正常对照组表达升高（P值均〈0．05），但二者相比差异无统计学意义（P〉0．05）；移植后allo—BMT—HF组CXCL9、CXCLl0表达明显高于allo-BMT组（P〈0．01），但未检测到CCL20。结论阻断Th17细胞分化加重allo—BMT小鼠小肠损伤。

Objective To study the role of Tb17 cells in acute intestine graft-versus-host disease fol- lowing allogenetic bone marrow transplantation （allo-BMT）. Methods Mice were split randomly into five groups： nomlal control, irradiated, allo-BMT, allo-BMT ＋ DMSO and allo-BMT ＋ Halofuginone （HF） groups . HF was given intraperitoneally at a dose of 5 p,g per mouse from - 1 d to 10 d after allo-BMT. aGVHD symptoms were followed-up to perform clinical and pathogenic scores. The levels of Thl/Th17, inter- leukin-17 and interferon-＇,/ were measured by flow cytometry at day 7 d. mRNA expressions of T-bet, ROR~/T, CXCL9, CXCL10, CXCL11 and CCL20 in intestine were evaluated by real-time PCR. Results In- testinal damages in allo-BMT-HF mice was more serious than in normal control and allo-BMT groups at day 14 after transplantation. At day 7, Th17 ratio in allo-BMT ＋ HF group was significantly lower than in allo-BMT group. IL-17A was not detected, but Thl ratio was higher in allo-BMT ＋ HF. There was a similar increment in the relative expressions of T-bet in both allo-BMT and allo-BMT ＋ HF groups. Expressions of CXCL9 and CXCL10 elevated in allo-BMT ＋ HF group, which were significantly higher than those in allo-BMT group （P〈0.01）. CCL20 expression significantly increased in allo-BMT group, but it was not detected in allo- BMT ＋ HF group. Conclusion Blockage of th17 cells differentiation exacerbated acute intestine graft versus- host disease. [ Key words] Stem cell transplantation; Th17 cells; Graft versus-host disease; Intestinal injury