CHI3L1 and asthma: Overexpression of chitotiosidase has been previously associated with abnormal production of TGF-beta, leading to initiation and perpetuation of interstitial lung disease in systemic sclerosis [9] and its expression, and of other chitinases (i.e. YKL-40), has been associated to airway remodelling in severe asthma [28, 29].