FOP lesions and the rapid spread of the lesion into adjacent tissue. As most patients and families know, these lesions may appear within hours and can reach an alarming size literally overnight. The sudden appearance and rapid spread of these lesions suggest involvement of an armada of inflammatory mediators along with an abnormal connective tissue wound response and points to a potential role for inflammatory mast cells in the the disease process.
Mast cells are indigenous cells in the body's connective tissues and arise from the bone marrow.
They circulate through the blood as committed but undifferentiated cells and migrate into numerous tissues including skeletal muscle where they mature and reside as harmless bystanders until provoked by a traumatic or inflammatory stimulus. Mast cells are found in close proximity to blood vessels and nerves. In normal skeletal muscle, mast cells are found very sparsely distributed in the connective tissues between the muscle bundles. All rights reserved.