评估冰冻过程对外周血造血干细胞细菌污染检测灵敏度的影响  

Investigation of the influence of freezing process on the sensitivity to detect bacterial contaminations in peripheral blood progenitor cell products

作　　者：朱立苇[1,2] 孙淼军 刘晋辉 ZHU Li-wei;SUN Miao-jun;LIU Jin-hui(Zhejiang Provincial Blood Center,Hangzhou,Zhejiang 310052,China;不详)

机构地区：[1]浙江省血液中心,浙江杭州310052 [2]浙江省血液安全研究重点实验室,浙江杭州310052

出　　处：《中国卫生检验杂志》2021年第10期1183-1185,1189,共4页Chinese Journal of Health Laboratory Technology

基　　金：浙江省科技计划项目(2017C33086);浙江省医药卫生面上项目(2018KY358)。

摘　　要：目的评估冰冻过程对外周血造血干细胞(PBPC)细菌污染检测灵敏度的影响。方法90袋放弃临床移植的PBPC产品随机分成6组(n=15),解冻后分别接种表皮葡萄球菌或大肠埃希菌标准菌株混悬液至浓度为10^(1)cfu/ml~103cfu/ml,振荡混匀60 min后,取样于营养琼脂上培养24 h计数菌落数。同时将血袋在-80℃冰冻保存7 d后解冻取样培养计数菌落数。采用90袋血浆以同样的方法进行平行试验。结果冰冻解冻后PBPC产品中表皮葡萄球菌平均浓度下降7.5%~13.9%,大肠埃希菌平均浓度下降10.4%~29.1%,差异有统计学意义(P<0.05)。冰冻解冻后血浆中表皮葡萄球菌平均浓度下降4.5%~12.0%,差异无统计学意义(P>0.05),大肠埃希菌平均浓度下降8.3%~17.6%,差异有统计学意义(P<0.05)。结论冰冻解冻过程可降低PBPC产品中污染菌的浓度,在PBPC产品细菌污染浓度较低的情况下可导致无菌试验假阴性,宜同时检测PBPC制备过程中分离的血浆和冰冻前的PBPC样本,提高无菌试验的灵敏度,降低细菌污染给移植受者带来的潜在风险。Objective To evaluate the effect of freezing process on the sensitivity of detecting bacterial contaminations in peripheral blood progenitor cell(PBPC)products.Methods Ninety units of PBPC products abandoned for clinical transplantation were randomly divided into 6 groups(n=15).After thaws,the suspension of Staphylococcus epidermidis or Escherichia coli standard strains were inoculated to the concentration of 10^(1) cfu/ml-10^(3) cfu/ml,respectively.After being mixed for 60 minutes,the samples were taken and cultured on nutrient agar plates for 24 hours to count the number of colonies.At the same time the PBPC products were cryopreserved and preserved at-80℃ for 7 days,and then another aliquot was drawn and cultured as mentioned above.The numbers of cfus were counted before and after cryopreservation.Ninety plasma units were treated and tested in the same manner.Results The mean concentration of S.epidermidis in PBPC products decreased by 7.5%-13.9% and that of E.coli decreased by 10.4%-29.1% after cryopreservation(P<0.05).The mean concentration of S.epidermidis in plasma decreased by 4.5%-12.0% after cryopreservation(P>0.05),and the mean concentration of E.coli decreased by 8.3%-17.6%(P<0.05).Conclusion The cryopreservation reduces the concentration of bacteria in contaminated PBPC products.Low concentrations of bacterial contamination in PBPC products can result in false-negative sterility tests.It is advisable to simultaneously detect plasma isolated during the preparation of PBPC and PBPC samples before freezing to improve the sensitivity of the sterility test and reduce the potential risk of bacterial contamination to transplant recipients.

关 键 词：外周血造血干细胞 细菌污染检测 灵敏度 

分 类 号：R446.5[医药卫生—诊断学]