Platelets in regeneration

Platelets, as the first cellular response after disruption of vascular and/or tissue integrity, cover any existing injury within our body. But is the regenerative potential of platelets limited to providing a cellular patch for wounds? This review highlights the recent advance in our understanding of platelets being distinctly regulated and regulating cells that contribute immensely to the healing process from the very initial stage to the late events of tissue regeneration. For instance, the intrinsic actions of platelets as a regenerative cell, the participation of platelets in angiogenic processes, and the interplay of platelets and circulating stem and progenitor cells, as well as potential therapeutic implications, are addressed. Although we are starting to understand the underlying mechanisms connecting platelets to the components of tissue regeneration just mentioned, many aspects remain to be elucidated. The demand to invest research in this area is underscored by the fact that platelets or platelet-derived molecules are already applied in clinical contexts such as connective tissue regeneration, whereas other research fields have largely neglected platelet effects going beyond their participation in the coagulation cascade. Understanding the mechanisms connecting platelets to tissue regeneration, however, will inevitably open novel options in regenerative medicine.