Background : Three cell separators are being used and they collect platelets with
different centrifuge speed and duration. Because centrifugation may cause platelet
activation, the differences of centrifuge speed and duration are important in controlling
the quality of apheresis platelet products. We compared many parameters of activation
of platelets collected by Spectra (Cobe BCT, Lakewood, CO, USA), CS3000p1us (Banter
Healthcare, Fenwal Division, Round Lake, IL, USA) and Mobile Collection
SystemTM (MCS, Haemonetics co., Braintree, MA, USA).
Methods : Platelets were collected from ninety-five normal donors with Spectra (n=39)
CS3000p1us (n=19) and MCS (n=37). We underwent the procedure according to the
automatic program set. We measured platelet yield and assayed pH, hypotonic shock
respose (HSR), CD62 (p-selectin, GMP140) expression and β-thromboglobulin in each
stored unit on day 0 and day 3 (or evaluation of the storage lesions.
Results : Platelet yield per product was 3.7±1.2×1011, mean final
product volume was 316±69mL and mean procession time was 100±19 minutes. Mean
collection efficiency was 42.5±8.3%. The cell separator volume of product collected by
CS3000p1us was the smallest while platelet concentration and total yield were the
highest in the product collected by Spectra. The pH of the products were 7.1±0.1 on
day 0 and 6.7± 0.4 on day 3 Hypotonic shock response was 69±13 % on day 0 and 28
±17 % on day 3. p-selectin expression was 19±9% (4.2±1.9 relative fluorescence
intensity, RFI) on day 0 and 60±22% (17.9±14.2) on day 3. β-thromboglobulin was
28.5±7.0 IU/107 platelets on day 0 and 31.3±7.2 IU/107
platelets on day 3. The comparison of the three cell separators showed that on day 0
platelet product of MCS has lower pH and higher β-thromboglobulin release than
others (p<0.05). And on day 3 platelet product of MDS has better hypotonic shock
response than others (p<0.05) Other parameters revealed no differences among three cell
separators. The expression of p-selectin was shown to correlate highly with pH
reduction (r=0.72), but not with the release of β-7G (r=0.24).
Conclusions : Most parameters showed no differences among three cell separators, but
apheresis platelet concentrates processed by MCS showed lower pH on day 0 and higher
β-thromboglobulin concentration on day 0 and day 3 than apheresis platelet
concentrates processed by Spectra or CS3000p1us and hypotonic shock response on day
3 was the lowest in CS3000p1us. So platelet activation produced during apheresis
processing was lowest in apheresis platelet concentrates with Spectra.