Hyperconcentrated platelets stored in additive solution: aspects on productivity and in vitro quality.
OBJECTIVE
New platelet (PLT) additive solutions (PASs) allow a plasma carryover of < 30% in PLT concentrates. This implicates the need to collect apheresis PLT concentrates at very high PLT concentrations: so-called dry PLTs (DPs). We used the TRIMA, with software version 4 (TRIMA V4), to collect such DPs and investigated the in vitro quality of these PLTs when stored in the new modified PAS-III (PAS-IIIM).


METHODS
TRIMA V4 was programmed to collect 6.0 x 10(11) PLTs at a concentration of 5000 x 10(3) PLTs/microl. Two DPs were pooled, split into four equal parts and diluted to obtain secondary pools (SPs) consisting of 70% PAS-III/30% plasma, 70% PAS-IIIM/30% plasma, 80% PAS-IIIM/20% plasma or 100% plasma. In vitro testing was performed on days 0, 1, 5 and 7. Collection efficiency (CE), collection rate (CR) and PLT yield were calculated for each donation.


RESULTS
Thirty-two runs with TRIMA V4 were performed, collecting 6.58 +/- 0.74 x 10(11) PLTs at a concentration of 4255 +/- 914 x 10(3)/microl in 99 +/- 19.9 min, resulting in a CE of 65.3 +/- 8.2% and a CR of 6.92 +/- 1.6 x 10(9) PLTs/min. On day 0, 34-37% of the PLTs in the units prepared for storage were already activated. PLTs stored in 70% or 80% PAS-IIIM showed superior in vitro quality compared to PLTs stored in PAS-III.


CONCLUSIONS
TRIMA V4 is a suitable device for the collection of DPs. Nevertheless, improvements are desirable to further increase the ability to concentrate PLTs at very high levels. The storage of apheresis-derived PLTs in PAS III-M is a very promising approach, even at a plasma carryover of < 30%.
Ringwald
J
J
Department for Transfusion Medicine and Haemostaseology, University Hospital of Erlangen, Erlangen, Germany. Juergen.Ringwald@trans.imed.uni-erlangen.de
Walz
S
S
Zimmermann
R
R
Zingsem
J
J
Strasser
E
E
Weisbach
V
V
Eckstein
R
R
D001792:Blood Platelets / Q000166:cytology / Q000201:enzymology / Q000378:metabolism; D001793:Blood Preservation / Q000379:methods* / Q000592:standards; D006801:Humans; D006863:Hydrogen-Ion Concentration; D019007:P-Selectin / Q000032:analysis; D010976:Platelet Count; D010983:Plateletpheresis / Q000592:standards; D012984:Software; D012996:Solutions
D019007:P-Selectin; D012996:Solutions