Mast cells and wound healing: Still an open question.

Mast cells, which originate from the bone marrow, possess the ability to secrete a diverse array of active molecules. These molecules include mediators (histamine, heparin), which have been identified for decades and are stored in specific granules, as well as small molecules generated instantaneously in response to stimulation (membrane lipid derivatives, nitric oxide), and a multitude of multifunctional cytokines that are secreted constitutively. Activated mast cells participate in the regulation of the local immune response and exert control over critical events of inflammation and healing with the assistance of a vast array of mediators. The involvement of these cell types in inflammatory states suggests that mast cells may function as sentinels that activate local immune processes in response to various types of stimuli and the entry of antigens. Moreover, due to their proximity to nerve fibers and reactivity to a variety of neurotransmitters, mast cells are among the cells that may facilitate local neuroimmune interactions. With this in mind, it is necessary to consider their participation in the repair of injuries in both acute and chronic conditions.