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To evaluate the efficiency and effectiveness of batch preparing cryopreserved fresh platelet-rich plasma (cryo-FPRP) derived from the volunteer donors, platelet count (Plt), mean platelet volume (MPV), platelet distribution width (PDW), plasma pH, plasma lactic acid concentration, and lactic dehydrogenase (LDH) concentration, germiculture, CD62p positive rate, PAC-1 positive rate, and the fluorescence intensity of platelet GPIb-IX-V were detected in ACD whole blood, fresh platelet-rich plasma (FPRP), FPRP with 5% dimethyl sulphoxide DMSO (DMSO-FPRP), and thawed cryopreserved FPRP (cryo-FPRP); the procoagulant activity of FPRP and cryo-FPR was determinated. The results showed that (1) 70 percentage of platelet were separated from the whole blood into FPRP, and the counts of residual erythrocyte and leucocyte were below 1 x 10(9), and below 1 x 10(7) per unit respectively. (2) The plasma pH, lactic acid concentration and PAC-1 positive rate retained a stable level during the preparing, storing and thawing process. (3) Plasma LDH concentration, platelet CD62p positive rate and GPIb-IX-V concentration in platelet surface were enhanced significantly after being frozen and thawing. (4) The plasma clotting time induced by cryo-FPRP were significantly shorter than that induced by FPRP. It is concluded that: (1) The batch platelet preparing process can efficiently obtain platelet from whole blood donated by volunteer, and the process didn't activate the platelet. (2) Cryopreservation can prevent lactic acid accumulation, pH reduce and activation of GPIIb/IIIa. (3) The membrane of partial platelets are affected by freezing and thawing. (4) The density of GPIb-IX-V complexes in platelet surface and its procoagulant activity are enhanced significantly after the FPRP freezing and thawing process.

The study was purposed to explore the suitable platelet activators to be used in slide platelet aggregation test. Experiments were as follows: (1) to detect the intensity and time in 15 healthy donors' platelet aggregation tests induced by cationic propyl gallate (c-PG) and the usual platelet activators: ADP, collagen, epinephrine, arachidonic acid and ristocentin, respectively; (2) to detect the time in platelet aggregation tests of 15 healthy donors induced by c-PG and the above usual platelet activators respectively after addition of PGI2, cAMP or EDTA; (3) to detect the time in 15 healthy donors' platelet aggregation tests induced by c-PG after addition of heparin; (4) to detect the intensity and time of platelet aggregation induced by c-PG at the platelet count of (240-15) x 10(9)/L, (5) to detect the time of platelet aggregation induced by c-PG in eight patients each of whom had taken 100 mg aspirin per day for five days. The results showed that (1) c-PG reduced the strongest intensity of platelet aggregation and the time taken was appropriate, (2) c-PG was the most effective activator to reveal the inhibitive effect on platelet by PGI2, cAMP or EDTA, (3) 0.5 - 3 U/ml heparin did not significantly change the platelet aggregation induced by c-PG, (4) 15 healthy donors' platelet aggregation induced by c-PG displayed clearly on the slide until the platelet count below 30 x 10(9)/L, (5) The platelet aggregation time induced by c-PG was significantly prolonged in eight patients who had taken aspirin. In conclusion, compared to the usual platelet activators, c-PG has remarkable potential advantages when used in slide platelet aggregation test.

CD62p expression was an important monitoring parameter for preserved platelets quality. To setup an optimized flow cytometry assay for preserved platelets based on the CD62p expression on platelets, the platelet samples were collected, 0.1 mmol/L persantine and 1.1 mmol/L EDTA were added into the modified TB S used to replace PBS dilution; the methodological evaluation were carried out. Results showed that 0.1 mmol/L persantine and 1.1 mmol/L EDTA achieved to prevent platelets activation during the test procedure. The favorable negative or positive samples were prepared for check of fluorescence antibody's quality to ensure the validity of results. CD61 was used to identify platelets for assay and improve veracity of assay. The special injector was also replaced by special big syringe needle for blood collection to reduce in vitro artifacts, and the prepared sample can be steady-going for 48 hours at 4 degrees C after fixed by 1% paraformaldehyde. It is concluded that this flow cytometry assay for CD62p positive platelets is simple and efficient.