IL33 and Hepatic fibrosis: Also, due to the fact that they are able to process extracellular matrix and activate pro-fibrotic cytokines such as IL-1β and IL-33 (Interleukin-33) (Gieling et al. 2009; Marvie et al. 2010), PR3 and NE might play an important role in the mechanisms of liver fibrosis.