Microparticles from stored red blood cells enhance procoagulant and proinflammatory activity

Transfusion. 2017 Nov;57(11):2701-2711. doi: 10.1111/trf.14268. Epub 2017 Aug 2.


Background: The pathomechanisms of morbidity due to blood transfusions are not yet entirely understood. Elevated levels of red blood cell-derived microparticles (RMPs) are found in coagulation-related pathologies and also in stored blood. Previous research has shown that RMPs mediate transfusion-related complications by the intrinsic pathway. We hypothesized that RMPs might play a role in post-transfusion thrombotic complications by enhancing procoagulant activity also through the extrinsic pathway of coagulation.

Study design and methods: In this laboratory study, blood from 18 healthy volunteers was stimulated with microparticles from expired stored red blood cells. Various clotting parameters were recorded. Flow cytometry, enzyme-linked immunosorbent assays, and real-time polymerase chain reaction were used to investigate possible mediating mechanisms.

Results: The addition of RMPs shortened the clotting time from 194 to 161 seconds (p < 0.001). After incubation with RMPs, there was increased expression of tissue factor (TF) on monocytes and in plasma. TF messenger RNA expression increased in a time-dependent and concentration-dependent manner. There was a significant induction of interleukin-1β and interleukin-6. After stimulation with RMPs, there was a significant increase in the number of activated platelets, an increased percentage of PAC-1/CD62P (procaspase activating compound-1/platelet surface P-selectin) double-positive platelets, and an increased number of platelet-neutrophil duplets and platelet-monocyte duplets, indicating enhanced interaction of platelets with neutrophils and monocytes. Levels of CXCL-8 (C-X-C motif chemokine ligand 1) and interleukin-6 were significantly higher after treatment with RMPs.

Conclusion: Our results suggest that RMPs trigger coagulation through TF signaling, induce the secretion of proinflammatory cytokines, and induce cell-cell interaction between platelets and neutrophils. Thus, under certain conditions, RMPs could play a role in post-transfusion complications through these mechanisms.

MeSH terms

  • Blood Coagulation*
  • Blood Preservation
  • Cell Communication
  • Cell-Derived Microparticles / physiology*
  • Erythrocytes / cytology*
  • Erythrocytes / ultrastructure
  • Humans
  • Inflammation* / etiology
  • Interleukin-6 / blood
  • Interleukin-8 / blood
  • Monocytes / metabolism
  • Platelet Activation
  • RNA, Messenger / blood
  • Thromboplastin / genetics
  • Thromboplastin / metabolism
  • Thrombosis / etiology
  • Transfusion Reaction*


  • CXCL8 protein, human
  • IL6 protein, human
  • Interleukin-6
  • Interleukin-8
  • RNA, Messenger
  • Thromboplastin