Drug-Loaded Microbubbles May Diagnose, Treat Thrombosis
(HealthDay News) — Targeted theranostic microbubbles (TT-MB), that consist of a fusion construct combining urokinase, echo-enhancing microbubbles for visualization by ultrasonography, and an activated platelet-specific single-chain antibody for specific targeting to thrombi, can diagnose and treat thrombosis. The findings were presented at the American Heart Association's Arteriosclerosis, Thrombosis and Vascular Biology/Peripheral Vascular Disease 2015 Scientific Sessions, held from May 7–9 in San Francisco.
Xiaowei Wang, PhD, from the Baker IDI Heart and Diabetes Institute in Melbourne, Australia, and colleagues hypothesized that thrombolytic drug-loaded MBs, which are selectively targeted to activated platelets, will allow high-resolution, real-time imaging of thrombosis. Experiments were conducted in the ferric chloride-induced carotid artery thrombosis mouse model.
The researchers found that treatment with TT-MB significantly reduced thrombus size after 45 minutes, while no significant difference was seen in the targeted MB without urokinase (37.09 vs. 97.14 mean percent change, normalized to baseline thrombus size; P<0.001). Efficient thrombolysis was only achievable to the same degree using a high dose of urokinase. The targeting and clot-enrichment effect of TT-MB resulted in a highly-potent fibrinolysis that could be only matched using high doses of non-targeted urokinase, but this was associated with a highly prolonged bleeding time (P<0.001). TT-MB did not prolong bleeding time.
"This unique technology holds promise for major progress towards rapid diagnosis and bleeding-free, potent therapy of the vast number of patients suffering from thrombotic diseases," the authors write.