Abstract:
Objective: To establish an acute graft-versus-host disease (aGVHD) model in aged mice after non-myeloablative haploidentical peripheral blood stem cell transplantation (haplo-PSCT). Methods: C57BL/6 (H-2b) male mice aged 6-8 weeks were used as donor mice, and CB6F1 (H-2b×d) female mice aged 14-16 months were used as recipient mice. The donor mice were injected subcutaneously with rehuman granulocyte-colony stimulating factor (rhG-CSF) 5 days before transplantation for hematopoietic stem cell mobilization.The recipient mice were divided into control group (CG), spleen cell low-dose group (SL), spleen cell medium-dose group (SM) and spleen cell high-dose group (SH) according to random number table method, with 16 rats in each group, all of which received total linear accelerator X-ray irradiation (TBI) with a total dose of 6 Gy. Peripheral blood mononuclear cells (PBMC) and spleen cells of different doses (0.5×107/each, 1.0×107/each and 2.0×107/each in SL group, SM group and SH group, respectively) were transfused through the tail vein within 4 hours after TBI, and only the same amount of normal saline was transfused in CG group. After transplantation, the survival and weight changes of mice in each group were observed for 30 days, and the changes of blood routine were monitored regularly. Mice peripheral blood was collected 21 days after transplantation to detect the chimerism rate of the donor. Hematoxylin-eosin staining was performed on the skin, liver and colon of mice 21 days after transplantation to analyze the histopathological changes of aGVHD target organs. Results: All the mice in each group were successfully transplanted. After TBI, the weight and activity of mice in all groups decreased, and the phenomenon of bone marrow suppression appeared. During the observation period, all mice in CG group and SL group survived, 3 mice in SM group died with survival time of (26.0±5.8) days, and 6 mice in SH group died with survival time of (20.9±7.3) days. The body weight of mice in SH group was lower than that in CG group, SL group and SM group 21days after transplantation [(25.0±0.7), (25.5±0.4), (25.0±1.4) vs (20.8±0.8) g, all P<0.05]. Compared with CG group, SL group and SM group, the levels of leukocyte, erythrocyte, hemoglobin and platelet in SH group decreased 21 days after transplantation (all P<0.05). There was no significant difference in donor chimerism rate among SL group, SM group and SH group [(95.8%±0.8%), (95.5%±1.4%) and (95.1%±1.3%), respectively, all P>0.05]. Compared with CG group, SL group and SM group, the tissue structure of aGVHD target organs in SH group was severely damaged, with a large number of inflammatory cells infiltratedand higher histopathological scores than SL group and SM group (all P<0.05). Conclusion: For aging CB6F1 mice, after 6 Gy TBI pretreatment with linear accelerator X-ray, PBMC (1×107/each) and spleen cells (2.0×107/each) were injected to successfully induce aGVHD model after non-myelablative haplo-PSCT.
目的: 构建老龄小鼠非清髓性单倍体外周血造血干细胞移植(haplo-PSCT)后的急性移植物抗宿主病(aGVHD)模型。 方法: 选用6~8周龄C57BL/6(H-2b)雄性小鼠作为供鼠,14~16月龄CB6F1(H-2b×d)雌性老龄鼠作为受鼠。供鼠于移植前5 d皮下注射人粒细胞集落刺激因子(rhG-CSF)进行造血干细胞动员;将受鼠按随机数字表法分为对照组(CG)、脾细胞低剂量组(SL)、脾细胞中剂量组(SM)、脾细胞高剂量组(SH),每组各16只,均接受总剂量为6 Gy的直线加速器X射线全身照射(TBI),照射后4 h内经尾静脉输注外周血单个核细胞(PBMC)和不同剂量的脾细胞(SL组、SM组和SH组分别为0.5×107/只、1.0×107/只和2.0×107/只),CG组仅输注等量生理盐水。移植后观察各组受鼠的生存情况及体重变化,观察期为30 d,并定期监测小鼠血常规变化。移植后21 d取小鼠外周血检测供体嵌合率。移植后21 d取小鼠颈背部皮肤、肝脏、结肠组织行苏木精-伊红染色,分析aGVHD靶器官的组织病理学变化情况。 结果: 各组小鼠均移植成功。各组小鼠TBI后体重、活动度均下降,并出现骨髓抑制现象。观察期内CG组和SL组小鼠全部存活,SM组死亡3只,生存时间为(26.0±5.8)d,SH组小鼠死亡6只,生存时间为(20.9±7.3)d。SH组小鼠体重呈持续下降的趋势,移植后21 d体重低于CG组、SL组和SM组[分别为(25.0±0.7)、(25.5±0.4)、(25.0±1.4)比(20.8±0.8)g,均P<0.05]。移植后21 d,与CG组、SL组和SM组相比,SH组小鼠白细胞、红细胞、血红蛋白及血小板水平降低(均P<0.05)。SL组、SM组和SH组供体嵌合率差异无统计学意义[分别为(95.8%±0.8%)、(95.5%±1.4%)和(95.1%±1.3%),均P>0.05]。与CG组、SL组、SM组相比,SH组aGVHD靶器官组织结构破坏严重,大量炎性细胞浸润,且组织病理学评分高于SL组、SM组(均P<0.05)。 结论: 对于老龄CB6F1小鼠,给予直线加速器X线6 Gy TBI预处理之后,输注PBMC(1×107/只)、脾细胞(2.0×107/只)能成功诱导出非清髓性haplo-PSCT后aGVHD模型。.