When plaques coating blood vessel walls rupture and expose collagen, platelets spring into action to form a blood clot at the damaged site. Now, a new report in the April 17th issue of the journal Cell, a Cell Press publication, reveals how those life-threatening clots—a leading cause of death in the United States, Europe and other industrialized countries--get an early grip. The discovery might offer a new way to fight clot formation before it can even begin, according to the researchers.