LEUKOCYTE-DERIVED BIOACTIVE SUBSTANCES IN FRESH-FROZEN PLASMA

Bioactive substances in fresh frozen plasma (FFP) are considered to be related to adverse reactions after transfusion, particularly in septi c or traumatized patients. Therefore, we analysed the concentration of various bioactive substances (histamine, eosinophil cationic protein, eosinophil protein X, myeloperoxidase and interleukin-6) in 25 u, of thawed FFP from healthy donors. These were compared with donor plasma concentrations of 24 healthy controls. In addition, we analysed the co ncentration of the bioactive substances, except interleukin-6, in 25 u . of thawed FFP, which were subjected to leucocyte filtration before f reezing and storage. Finally, we analysed the substances in 10 leucocy te non-filtered plasma units before freezing and storage, and after th awing, respectively. Before analyses, which were performed by ELISA an d RIA methods, these latter samples were sterile filtered through a 0. 20-mu m filter. Histamine, eosinophil cationic protein, eosinophil pro tein X and myeloperoxidase concentrations were significantly greater ( P<0.05) in the 25 u. of FFP compared with normal donor plasma. Pre-sto rage leucocyte filtration reduced concentrations of the bioactive subs tances in FFP to concentrations comparable with normal donor plasma co ncentrations. Interleukin-g was undetectable in all FFP units and in 2 1 of the 24 control donors. Histamine, eosinophil cationic protein and myeloperoxidase concentrations were significantly higher (P<0.05) in samples collected from the 10 u, of FFP after freezing and thawing com pared with samples collected before freezing. We conclude that fresh f rozen plasma prepared by a conventional separation method contains var ious leucocyte-derived bioactive substances, which may be reduced by p re-storage leucocyte filtration.