MMP9 and asthma: The predominant gelatinase expressed by macrophages and neutrophils in inflammatory conditions such as emphysema, asthma, sepsis and inflammatory bowel disease is MMP-9 (Finlay et al, 1997; Mautino et al, 1997; Pugin et al, 1999), which is in keeping with the significantly elevated activity of this enzyme seen in IP specimens compared to either MM or UP samples.