异基因骨髓移植混合嵌合体小鼠模型的构建及影响因素分析

Establishment of A Mixed Chimeric Mouse Model of Allogeneic Bone Marrow Transplantation and Its Influencing Factors

目的:构建小鼠异基因骨髓移植(allogeneic bone marrow transplantation,allo-BMT)混合嵌合体(mixed chimerism,MC)模型,分析影响移植后嵌合水平的相关因素并建立数学模型。方法:通过非清髓allo-BMT联合移植后大剂量环磷酰胺构建MC模型,对构建过程中的123只小鼠进行回顾性研究,对影响其嵌合状态的相关因素进行单因素及多因素Logistic回归分析,并通过R语言进行多元线性回归获得以相关影响因素预测嵌合水平的数学模型。结果:该模型在移植后第14天呈现混合嵌合,第15天供者淋巴细胞(donor lymphocyte infusion,DLI)输注可显著促进后期供体细胞的植入,而PBS对照组植入失败。123只小鼠中,MC和非MC分别有47只(38.21%)、76只(61.79%);单因素分析结果显示,小鼠的基线体重(P=0.001,17.84±1.19 vs 18.50±0.94 g)、预处理条件全身照射(total body irradiation,TBI;P=0.048)及是否加用环磷酰胺(P=0.16)会影响小鼠的嵌合状态,而移植的细胞数及检测时间对其无明显影响。多因素回归分析结果显示,在一定条件下,小鼠基线体重是影响后期嵌合水平的独立因素(OR=0.493,95%CI 0.307-0.791,P=0.003)。经R语言多元线性回归得数学模型:chimerism=6.09-12×weight(g)+80.03×TBI(Gy)-4.4×cell-counts(×10^(7))+0.38×CTX(mg/kg),R^(2)=0.5841,P<0.001。结论:本研究建立了移植后混合嵌合体小鼠模型的构建方法;并建立了影响因素的数学模型。

Objective:To establish a mouse mixed chimerism(MC)model of nonmyeloablative allogeneic bone marrow transplantation(allo-BMT)and explore its affecting factors.Methods:The MC model was established by nonmyeloablative allo-BMT followed by high-dose post-transplant cyclophosphamide(PTCY).123 mice in the experiments was retrospectively analyzed,and the factors related with the chimerism were explored with the univariate and multivariate logistic regression analysis.A multivariate linear regression was performed by R project to obtain a mathematical model for predicting the chimeric level with relevant affecting factors.Results:The model presented mixed chimerism on day 14 after transplantation,and was characterized by a donor lymphocyte infusion(DLI)which significantly promoted donor engraftment on day 15,but transfplantation of PBS in control group was failed.Among 123 mice,47(38.21%)mice were MC,while 76(61.79%)mice were non-MC in 123 mice,respectively;univariate analysis showed that the baseline body weight of mice(P=0.001,17.84±1.19 g vs 18.50±0.94 g),total body irradiation(TBI,P=0.048)and the using of cyclophosphamide(P=0.16)were affected the chimeric state of mice,while the number of infusing cells and the time of detection showed no significant effects.Multivariate regression analysis showed that under certain conditions,the body weight of mice on day 0 was an independent factor affecting chimeric levels(OR=0.493,95%CI 0.307-0.791,P=0.003).Through R project multiple linear regression,the math model was achieved,which was chimerism=6.09-12×weight(g)+80.03 × TBI(Gy)-4.4 × cell-counts(×10^(7))+0.38×CTX(mg/kg),R^(2)=0.5841,P<0.001.Conclusion:The experiment presents a method for establishing a mixed chimeric mice model after non-myeloablative bone marrow transplantation and constructs a mathematical model with relevant factors affected chimerism status.