CD41-YFP mice allow in vivo labeling of megakaryocytic cells and reveal a subset of platelets hyperreactive to thrombin stimulation

The newly developed mouse line should become useful not only for in vivo imaging experiments of megakaryocytes and platelets, but also for studies on platelet aging and function. Our irradiation experiments suggest that the YFP+ platelets are enriched for newly made cells because YFP has a shorter half-life than platelets. Therefore, the finding that YFP+ platelets are more responsive to thrombin stimulation raises the possibility that platelet activity decreases rapidly during physiological aging.