同种异基因骨髓移植GVHD动物模型的建立及其病理生理学机制初探

目的：建立稳定的异基因骨髓移植GVHD（移植物抗宿主病）动物模型，并初步了解其病理生理学机制。方法：以BALB／c（H-2^d）雌性小鼠为受者，接受8Gy致死剂量的。Co全身照射后，输注雄性C57BL／6（H-2^b）供鼠的脾细胞和骨髓细胞，观察受鼠的体征、造血功能恢复及生存时间的变化，并进行病理学、嵌合体和T细胞亚群及相关细胞因子的检查。结果：模型组小鼠在移植后出现了典型的GVHD症状；肠、肝、脾、皮肤的病理学分析均属于Ⅳ度GVHD；嵌合体植入成功；以7、14和21d为检测时间点，发现模型组鼠体内T细胞亚群移植后较移植前CD3^＋CD4^＋T细胞数量减少，CD3＋CD8＋T细胞显著升高，CD4^＋和CD8^＋T细胞比例严重倒置，随着时间变化比值会逐渐升高，但仍然处于较显著的倒置水平；血清中IFN-γ、TNF-α在移植后＋7d表达显著增高，尤其是IFN-γ的表达在＋7d达峰值；IL-4和IL-10的水平在移植前后几乎没有变化。结论：建立了稳定的GVHD动物模型；此模型发病过程中，CD8^＋T细胞介导的CTL细胞毒性作用可能要大于CD4＋Th介导的细胞因子效应；IFN-γ、TNF-α炎症因子在GVHD的早期发挥重要作用；IL-4、IL-10的低水平分泌与急性GVHD的高发病率有关。

Establishment and Pathophysiology Study of Allogeneic Bone Marrow Transplantation Model for Graft-Versus-Host Disease

Objective： To establish a stable model of graft-versus-host disease （GVHD） after allogeneic bone marrow transplantation, and study its pathophysiology preliminary. Methods： The donor（male C57BL/6） bone marrow cells plus splenocytes were transfused into the recipient （female BALB/c） mice which were conditioned with 8 Gy ^60Co lethal total body irradiation. Then, general signs, hematopoiesis recovery, survival time, and chimera should be observed; and pathology section, T cell subsets, cytokines should also be detected. Results： There are typical signs of GVHD in our model mice, as weight loss, depilation, diarrhea and hunched posture, et al; WBC〉1×10^9/L when they died; median survival time is the day 22; histopathology of the gut, liver, spleen and skin illuminate that the fourth grad GVHD has occurred; chimera were observed in the recipients; CD3^＋CD4^＋ T cells obviously decreased, while CD3^＋CD8^＋ T cells markedly increased, and the ratio between the CD4^＋ and CD8^＋ T cells were severely inverted contrasting to the pretransplant. The levels of serum IFN-γ,TNF-α markedly increased on day 7 post-transplantation. No significantly changes on levels of IL-4 and IL-10 pre-and post-transplantation. Conelution： A stable GVHD animal model has been established. CD8^＋ T cell-mediated toxicity of the CTL have a greater effect on GVHD pathogenesis than CD4^＋ Th-mediated immune response. IFN-γ, TNF-α inflammatory cytokines play a important role in early GVHD. The low level secretion of IL-4, IL-10 related to the high incidence of GVHD.