Antibody-Armed Platelets for the Regenerative Targeting of Endogenous Stem Cells

Stem cell therapies have shown promise in treating acute and chronic ischemic heart disease. However, current therapies are limited by the low retention and poor integration of injected cells in the injured tissue. Taking advantage of the natural infarct-homing ability of platelets, we engineered CD34 antibody-linked platelets (P-CD34) to capture circulating CD34-positive endogenous stem cells and direct them to the injured heart. In vitro, P-CD34 could bind to damaged aortas and capture endogenous stem cells in whole blood. In a mouse model of acute myocardial infarction, P-CD34 accumulated in the injured heart after intravenous administration, leading to a concentration of endogenous CD34 stem cells in the injured heart for effective heart repair. This represents a new technology for endogenous stem cell therapy.