Procoagulant microparticles and nanoparticles from whole blood reconstituted with age-different blood components.

M. Ponschab1,2, C. J. Schlimp1,3, L. Wisgrill1, A. Spittler1, C. Gabriel2, J. Zipperle1, G. E. Iapichino1,4, H. Redl1, H. Schöchl1,5 (1Vienna, Austria, 2Linz, Austria, 3Edinburgh, United Kingdom, 4Milan, Italy, 5Salzburg, Austria)

Acquired problems and alterations of coagulation
Date: 17.02.2017,
Time: 17:15 - 18:15

Objective: Haemostatic potential of blood products depend on storage duration. Microparticles (MP) and exosomes (NP) are released after blood manufacturing process and their concentration increases over time. Furthermore, the procoagulant properties of MP and NP have been previously shown. The aim of this study was to compare the hemostatic capacity of leuko-depleted-whole blood (LD-RWB) versus reconstituted blood using either solvent-detergent treated plasma (SD-RWB) or prethawed plasma (PT-RWB) versus fresh whole blood (WB), with the hypothesis that despite loss of function of platelets and coagulation factors over days of storage, the increase in MP and NP procoagulant action would counteract the former resulting in maintained or increased haemostatic capacity.

Methods: WB was donated from 10 donors at Linz Blood Bank of the red Cross. We produced LD-RWB by adding Platelet Concentrate (PC) to LD blood; the other groups were obtained by mixing RBC, PC and either SD treated plasma or PT plasma. All components were mixed at different shelf age (days 0-1-3-5). These aliquots were tested with ROTEM EXTEM and INTEM assays. We then obtained MP and NP from the RWB aliquots by centrifugation and flow cytometry. Finally we spiked WB of healthy donors (n=10) with MP and NP fraction and tested it with ROTEM NATEM assay.

Results: EXTEM MCF and INTEM MCF were significantly increased over time in the SD-RWB and PT-RWB groups (Figure 1). This was paralleled by an increase in MP and NP with increasing age of blood components (Fig 2). WB of healthy donors spiked with MP and NP consistently showed a reduction in the NATEM clotting time (Figure 3).

Conclusion: Increasing the age of blood component from 0 to 5 days led to an increase in the clot firmness as evaluated by EXTEM and INTEM assay. A contemporary rise in MP and NP was noted in the RWB samples. We finally proved that MP and NP exert procoagulant effects on WB freshly collected from donors. We could then speculate that the increase in clot firmness noted in the RWB aliquots would originate from these small, hemostatically active particles.