Are changes in integrin affinity and conformation overemphasized?

The activation of integrin-type adhesion receptors might result in the increased affinity of the receptor for ligand. In addition, the activated receptor might display new epitopes, which are increasingly monitored in clinical settings. Here, we highlight examples of integrin 'activation' that is not accompanied by enhanced ligand binding. Also, we emphasize that the dominant integrin conformational changes occur not with 'activation', but after integrins have already bound ligand.