不同条件环磷酰胺建立小鼠免疫力低下模型的比较及偏最小二乘法(PLS)数学建模分析

Cyclophosphamide-induced immunosuppressive mouse models established under different conditions and mathematical modeling analysis with partial least squares

目的通过比较4种不同剂量、周期的环磷酰胺建立小鼠免疫力低下模型,并采用偏最小二乘法（PLS）建模分析筛选出最优方案。方法雄性昆明小鼠58只随机分成5组,分别为正常组10只,每日注射生理盐水;模型1组12只,按照40 mg/kg的剂量连续注射环磷酰胺溶液10 d;模型2组12只,按照80 mg/kg的剂量连续注射环磷酰胺溶液3 d;模型3组12只按照40 mg/kg的剂量注射2次环磷酰胺溶液,每次间隔（2-3）d;模型4组12只按照50 mg/kg的剂量连续注射环磷酰胺溶液7 d。监测不同剂量和不同周期给予小鼠环磷酰胺后,模型小鼠的饮食、饮水、体重等日常代谢指标的变化;测定小鼠胸腺、脾等脏器指数以及血常规等免疫指标的变化;采用SIMCA-P软件处理小鼠的终体重、终肛温、脏器指数、血常规等指标,应用偏最小二乘法（PLS）综合评价免疫力低下小鼠模型的建立。结果与正常组相比,模型组小鼠体重和肛温降低且差别有显著性意义（P〈0.05）;日平均饮食、饮水量降低且差异有显著性（P〈0.01）;脾指数和胸腺指数降低且差别有极显著性意义（P〈0.01）;模型组嗜碱细胞绝对值和嗜碱细胞百分比均降低且差异有显著性（P〈0.05）,模型组平均RBC血红蛋白浓度、大血小板比率均升高且有显著性差异,模型1组、模型2组、模型4组的白细胞、淋巴细胞绝对值均降低且差异有显著性（P〈0.05）。PLS分析处理表明,模型1组、模型2组、模型4组与正常组比较差异都具有显著性（P〈0.01）,其中模型1组差异最大。结论通过PLS分析方法综合不同指标,模型1组按照40 mg/kg的剂量连续注射10 d为最佳造模方法,为建立稳定的免疫力低下模型提供实验依据。

Objective Comparing four groups of immunosuppressive mouse models established by cyclophosphamide administration in different doses and periods,we used partial least squares（ PLS） analysis to evaluatethe immunosuppressive mouse models comprehensively and select the appropriate way to establish this model. Methods In this experimental study,58 male KM mice were randomly divided into five groups： normal group（ 10 mice） were given normal saline daily by i. p. injection,model group 1（ 12 mice） was given 40 mg / kg CTX daily by i. p. injection for 10 days,model group 2（ 12 mice） was given 80 mg / kg CTX daily by i. p. injection for 3 days,model group 3（ 12 mice） was given 40 mg / kg CTX daily by i. p. injection twice for a week,model group 4（ 12 mice） was given 50 mg / kg CTX daily by i. p. injection for 7 days. After the injection of cyclophosphamide,the daily metabolic activities were detected everyday such as body weight,water intake,and food intake,organ index and immunological indexes such as blood RT of the model mice were measured as well. Using partial least squares（ PLS） analysis to the models and analyzing the final weight,final anal temperature,organ index,and blood routine examination in order to evaluate the immunosuppressive mouse models comprehensively. Results Compared with the normal group,different dosages of CTX reduced the weight and anal temperature of model mice（ P〈0. 05）,the food intake and water intake（ P〈0. 01）,and the spleen index and thymus index（ P〈0. 01）. Besides,the amount and percentage of basophilic granulocytes decreased（ P〈0. 05）,and the percentage of MCHC,macrophage went up,as well as the absolute value of WBC and lymphocytes were decreased in the model groups 1,2,and 4（ P〈0. 05）. According to the PLS analysis,there were significant differences among models 1,2,and 4 when compared with the normal group,especially the most different in the model group 1. Conclusions After the PLS analysis of different indexes,the optimal way to establish immunosuppressive mouse models is the procedure with40 mg / kg CTX daily injected i. p. for ten days. Our findings provide experimental evidence for the establishment of immunosuppressive mouse models.