Platelet Integrins and Signaling

The term integrin describes an adhesion molecule family and originates from the integrative function of these molecules between extracellular ligands and the intracellular cytoskeleton ( 1 , 2 ). Integrins mediate cell-cell, cell-extracellular matrix, and cell-pathogen interactions. Integrins have two major functions: First, they mechanically couple the cytoskeleton to the extracellular matrix or to surface receptors of other cells. Second, they transmit signals from the inside of the cell to the outside of the cell and vice versa ( 3 ). At least 24 different integrins are known in vertebrates (Fig. 1). Resting platelets express integrins α 2 β 1 , α 5 β 1 , α 6 β 1 , α v β 3 , and α IIb β 3 ( 4 ). In addition to these, α L β 2 and α M β 2 expression on activated platelets has been reported ( 5 ). These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.