CXCL8 and asthma: While the matrikine tumstatin conveys protection from experimental features of asthma and asthma exacerbation, a collagen I derived matrikine (PGP, Acetylated-(Ac) PGP) has been shown to be a more potent inducer of neutrophil chemotaxis then IL-8 and is found to be increased in severe asthmatics, a group of patients prone to develop exacerbations (283, 289).