Freeze-drying of human platelets: influence of saccharide, freezing rate and cell concentration.
Freeze-drying of human platelets is one potentially ideal approach for long-term preservation of platelets. In this study, effects of concentration and type of saccharides, freezing rate and initial cell concentration on the recovery of freeze-dried platelets were investigated. Annexin V binding platelet activation assays, scanning electron microscopy and platelet aggregation upon thrombin (1 U/ml) addition were used to evaluate the effectiveness of platelet freeze-drying. The numerical recovery of freeze-dried platelets was reached as high as 93.0+/-5.2 percent and the recovery of nonactive platelets was reached up to 85.7 +/- 3.4 percent in the presence of 1% BSA and 20% trehalose. Frozen by shelf pre-cooling was the best way to freeze the sample in this study and the numerical recovery of freeze-dried platelets was reached 93.0 +/- 5.2 percent at about 10 degree C/min. When the platelet concentration was increased from 0.2 to 4x10(9) platelets/ml, recovery remained higher than 81.4 percent. The morphology of freeze-dried and rehydrated platelets was intact but a little rounder compared with fresh platelets. The maximum aggregation rate to thrombin (1 U/ml) of freeze-dried platelets was 83.9 percent of the fresh ones, but aggregation speed was 43.0 percent of the fresh ones. Further research on rehydration process and scale up are required.
Zhou
Xin-Li
XL
Institute of Biothermal Sciences, University of Shanghai for Science and Technology, Shanghai 200093, China.
Zhu
Hong
H
Zhang
Shao-Zhi
SZ
Zhu
Fa-Ming
FM
Chen
Guang-Ming
GM
Yan
Li-Xing
LX
D017304:Annexin A5 / Q000378:metabolism; D001792:Blood Platelets / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology / Q000648:ultrastructure; D004305:Dose-Response Relationship, Drug; D004338:Drug Combinations; D005612:Freeze Drying; D005615:Freezing; D006801:Humans; D008855:Microscopy, Electron, Scanning; D009005:Monosaccharides / Q000008:administration & dosage / Q000494:pharmacology*; D009994:Osmolar Concentration; D015539:Platelet Activation; D010974:Platelet Aggregation / Q000187:drug effects; D010976:Platelet Count; D011134:Polysaccharides / Q000008:administration & dosage / Q000494:pharmacology*; D012710:Serum Albumin, Bovine / Q000494:pharmacology; D013917:Thrombin / Q000494:pharmacology; D013997:Time Factors; D014199:Trehalose / Q000494:pharmacology
D017304:Annexin A5; D004338:Drug Combinations; D009005:Monosaccharides; D011134:Polysaccharides; D012710:Serum Albumin, Bovine; D014199:Trehalose; D013917:Thrombin