ABSTRACT
To study the formation and change of platelet leucocyte aggregation (PLA) in red blood cell concentrations(CRCs) stored at 4℃ and the preventive effectiveness of filtration, 8 units of CRCs were each divided into two equal parts in two integrative bags and two paired groups were formed: control group and filtration group. The following items of control group and filtration group were detected weekly. Platelet and leukocyte counts, concentration and percentage of platelet lympocyte (P lym), platelet monocyte (P mon), platelet neutrophil (P neu) aggregatoins, and concentration of total PLA. The results showed that rate and concentration of PLA in the control group were significanly higher than those in the circulating blood. The rates of P lym and P mon in CRCs stored at 4 ℃ were two to five times of those before storage, and the rate of P neu in CRCs stored at 4 ℃ was ten to twenty times of that before storage. PLA in the CRCs separated from plasma rose to a high level at the first day of preparation. The concentration of PLA in CRCs reached the highest level at one week after stored at 4 ℃ and then decreased, but a high concentration was retained all the while. P neu is the major part (about 80%～90%) of whole PLA in CRCs. PLA was not detectable by flow cytometry during the whole storage course. The results suggested that high concentrated PLA was detected in CRCs stored at 4 ℃, which could be prevented by leucocyte depleting filtration.