Effect of recombinant ADAMTS-13 on microthrombosis and brain injury after experimental subarachnoid hemorrhage

Summary Background A common complication after aneurysmal subarachnoid hemorrhage (SAH) is delayed cerebral ischemia (DCI), which is associated with vasospasm and other mechanisms such as microthrombosis. ADAMTS-13 activity plays a role in the prevention of thrombus formation in the cerebral microvasculature. Previously, we observed that patients with DCI have lower levels of ADAMTS-13. Objectives To examine whether recombinant human ADAMTS-13 (rADAMTS-13) reduces cerebral microthrombus formation and brain injury in an experimental mouse model of SAH including wild-type and ADAMTS-13−/− mice. Methods Experimental SAH was induced with the prechiasmatic blood injection model. The following experimental groups were investigated: (i) C57BL/6J mice (n = 10); (ii) C57BL/6J mice (n = 10) treated with rADAMTS-13 20 min after SAH; (iii) ADAMTS-13−/− mice (n = 10); and (iv) ADAMTS-13−/− mice (n = 10) treated with rADAMTS-13 20 min after SAH. Mice were killed at 48 h. Results are presented as means with standard errors of the mean. Results Infusion with rADAMTS-13 reduced the extent of microthrombosis by ~ 50% in both wild-type mice (mean fibrinogen area: 0.28% ± 0.09% vs. 0.15% ± 0.04%; P = 0.20) and ADAMTS-13−/− mice (mean fibrinogen area: 0.32% ± 0.05% vs. 0.16% ± 0.03%; P = 0.016). In addition, rADAMTS-13 reduced brain injury by > 60% in both wild-type mice (mean microglia area: 0.65% ± 0.18% vs. 0.18% ± 0.04%; P = 0.013) and ADAMTS-13−/− mice (mean microglia area: 1.24% ± 0.36% vs. 0.42% ± 0.13%; P = 0.077). Conclusions Our results support the further study of rADAMTS-13 as a treatment option for the prevention of microthrombosis and brain injury after SAH.