Recombinant factor VIIa, its clinical properties, and the tissue factor pathway of coagulation

Red Blood Cell Microparticles Limit Hematoma Growth in Intracerebral Hemorrhage

BACKGROUND

Spontaneous intracerebral hemorrhage (sICH) is the deadliest stroke subtype with no effective therapies. Limiting hematoma expansion is a promising therapeutic approach. Red blood cell-derived microparticles (RMPs) are novel hemostatic agents. Therefore, we studied the potential of RMPs in limiting hematoma growth and improving outcomes post-sICH.

METHODS

sICH was induced in rats by intrastriatal injection of collagenase. RMPs were prepared from human RBCs by high-pressure extrusion. Behavioral and hematoma/lesion volume assessment were done post-sICH. The optimal dose, dosing regimen, and therapeutic time window of RMP therapy required to limit hematoma growth post-sICH were determined. We also evaluated the effect of RMPs on long-term behavioral and histopathologic outcomes post-sICH.

RESULTS

RMP treatment limited hematoma growth following sICH. Hematoma volume (mm3) for vehicle- and RMP- (2.66×1010 particles/kg) treated group was 143±8 and 86±4, respectively. The optimal RMP dosing regimen that limits hematoma expansion was identified. RMPs limit hematoma volume when administered up to 4.5-hour post-sICH. Hematoma volume in the 4.5-hour post-sICH RMP treatment group was lower by 24% when compared with the control group. RMP treatment also improved long-term histopathologic and behavioral outcomes post-sICH.

CONCLUSIONS

Our results demonstrate that RMP therapy limits hematoma growth and improves outcomes post-sICH in a rodent model. Therefore, RMPs have the potential to limit hematoma growth in sICH patients.