Science Daily Stanford scientists have uncovered how mRNA COVID-19 vaccines can very rarely trigger heart inflammation in young men — and how that risk might be reduced. They found that the vaccines can spark a two-step immune reaction that floods the body with inflammatory signals, drawing aggressive immune cells into the heart and causing temporary injury. By combining modern laboratory techniques with previously published data from vaccinated individuals, the team uncovered a two-stage immune response. In this process, the vaccine activates one type of immune cell, which then stimulates another. Together, these immune reactions drive inflammation that can damage heart muscle cells and set off additional inflammatory effects.
