MMP1 and asthma: Other MMPs such as MMP10 have been associated with MC activation, airway remodeling, and extracellular matrix (ECM) organization in severe asthma [54], while airway smooth muscle-derived MMP1 was activated by MC tryptase enabling the development of a proliferative ECM that may account for the association with a link to airway responsiveness in severe asthma [35].