不同冻干保护体系对海藻糖负载红细胞冻干保存影响的研究

本研究旨在评价冻干保护剂人血白蛋白、葡聚糖、聚乙烯吡咯烷酮和甘油对海藻糖负载后红细胞冰冻干燥保存的影响,筛选最佳冻干保护体系。将浓缩红细胞在37℃,浓度为800 mmol/L的海藻糖溶液中孵育7 h,经PBS液冲洗3遍后制成海藻糖负载的浓缩红细胞。对照组为海藻糖负载红细胞不添加保护剂,直接冻干;实验组将人血白蛋白、葡聚糖、聚乙烯吡咯烷酮、甘油等组成的冻干保护体系与海藻糖负载浓缩红细胞混合,两组样品在常温下平衡30 min,移入-80℃深低温冰箱,预冻24 h,入冻干机冻干处理24 h。用温度为37℃,6%羟乙基淀粉40注射液快速再水化样品,用氰化血红蛋白试剂盒测定血红蛋白溶血率,计算血红蛋白回收率,同时测定干燥样品含水量。结果表明：当样品含水量在3%-4%时,对照组冻干红细胞血红蛋白回收率为（33.57±2.89）%,白蛋白组血红蛋白回收率为（51.15±1.98）%,差异有显著性意义（P〈0.05）。选用不同浓度的葡聚糖为冻干保护剂,血红蛋白回收率较对照组明显降低,随浓度增加,血红蛋白回收率逐渐升高,当浓度为36%时,血红蛋白回收率为（22.15±4.12）%,差异有显著性意义（P〈0.05）。不同浓度的聚乙烯吡咯烷酮（PVP）组成的冻干保护体系,当浓度小于40%时,血红蛋白回收率明显低于对照组,差异有显著性意义（P〈0.05）。10%甘油组血红蛋白回收率为（3.93±1.80）%,差异有显著性意义（P〈0.05）。结论：人血白蛋白在海藻糖负载的冻干红细胞中发挥重要保护作用,葡聚糖与浓度小于40%PVP可削弱细胞内海藻糖的保护作用。液态的甘油不宜作为红细胞冰冻干燥保存的保护剂。

Effects of Different Lyophilizing Protectants on Lyophilized Trehalose-loading Red Blood Cells

This study was purposed to evaluate the effect of different lyophilizing protectants including human albu min, glucan, polyvinyl pyrrolidone and glycerine on lyophilized trehalose-loading red blood cells （ RBC）, then to screen the optimal lyophilizing protectant. The RBC were incubated in 800 mmol/L concentration of trehalose solution at 37（2 for 7 hours, and washed 3 times with PBS solution to obtain the trehalose-loading RBC. The trehalose-loading RBC in control group were directly lyophilized without lyophilizing protectants, the trehalose-loading RBC in the experimental group were mixed with Lyophilizing protectants. The samples of 2 groups were kept at room temperature for 30 minutes, pre-frozen at - 80℃ for 24 hours, then lyophilized in freeze-dryer for 24 hours. Finally the samples were quickly rehydrated by 6% HES at 37℃. The recovery rate and hemolysis rate of hemoglobin were detected by using cyanohemeglobin detection kit. The water content of unhydrated samples were detected at the same time. The results showed that when the moisture content of sample was 3% -5%, the recovery rate of hemoglobin in control group was 33.57 ±2.89% , and that in experimental group was 51.15±1.98%, there was statistically significant difference between the control and experimental group （ P 〈 0.05 ）. When the different concentration of dextran solution was chosen as protectants, the re covery rate of hemoglobin of lyophilized RBC was obviously lower. The higher concentration of dextran, the better the recovery rate. The recovery rate of hemoglobin was 22.15 ± 4.12% when the concentration of dextran was 36%, there were statistically significant difference between the two groups（ P 〈 0.05 ）. When the different concentration of polyvinyl pyrrolidone （PVP） solutions was chosen as protectants, especially the concentration below 40%, the recovery rate ofhemoglobin of lyophilized RBC was significantly belower than the control group, there was statistically significant difference between the two groups（P 〈0.05）. When 10% glycerol was used as protectants, the recovery rate of hemoglobin was 3.93 ± 1.80%. There was also statistically significant difference between the two groups（ P 〈 0.05 ）. It is concluded that human serum albumin shows an important protective effect on the lyophilization of the trehalose-loading red blood cells. The dextran and PVP at the concentration lower than 40% can decrease the protective effect of trehalose in cells. Glycerol can not be chosen as protectant for lyophilized trehalose-loading red blood cells.