PARTIAL CHARACTERIZATION OF LIPIDS THAT DEVELOP DURING THE ROUTINE STORAGE OF BLOOD AND PRIME THE NEUTROPHIL NADPH OXIDASE

Factors developed during the routine storage of whole blood and packed red blood cells that primed the neutrophil (PMN) reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidase significantly by 2 wee ks of storage, with maximal priming activity by product outdate (2.5 t o 3.7 fold). These agents appeared to be generated by cellular constit uents because stored, acellular plasma did not demonstrate PMN priming . The priming activity was soluble in chloroform. Priming of the oxida se by plasma and plasma extracts was inhibited by WEB 2170, a platelet -activating factor (PAF) receptor antagonist. Separation of the chloro form-soluble compounds from plasma by normal phase high-performance li quid chromatography demonstrated two peaks of priming activity at the retention times of neutral lipids and lysophosphatidylcholines (lyso-P Cs) for both whole blood and packed red brood cells. Analysis of the l atter peak of PMN priming by fast atom bombardment mass spectroscopy i dentified several specific lyse-PC species including C-16 and C-18 lys o-PAF. Further evaluation by gas chromatography/mass spectroscopy demo nstrated that three of these species increased dramatically over produ ct storage time, while the other two species increased modestly, and p aralleled the increase in priming activity. Commercially available, pu rified mixtures of these lyso-PCs primed the PMN oxidase by twofold. W hen PMNs were incubated with this mixture of lyso-PCs, acetylated anal ogs of these compounds rapidly accumulated. Thus lipids, including spe cific lyse-PC species, develop during routine storage of cellular bloo d components, prime PMNs, and possibly play a role in the severe compl ications of transfusion therapy.