protein_function: Carbohydrate-binding lectin with a preference forchitin. Has no chitinase activity. May play a role in tissueremodeling and in the capacity of cells to respond to and copewith changes in their environment. Plays a role in T-helper celltype 2 (Th2) inflammatory response and IL-13-induced inflammation,regulating allergen sensitization, inflammatory cell apoptosis,dendritic cell accumulation and M2 macrophage differentiation.Facilitates invasion of pathogenic enteric bacteria into colonicmucosa and lymphoid organs. Mediates activation of AKT1 signalingpathway and subsequent IL8 production in colonic epithelial cells.Regulates antibacterial responses in lung by contributing tomacrophage bacterial killing, controlling bacterial disseminationand augmenting host tolerance. Also regulates hyperoxia-inducedinjury, inflammation and epithelial apoptosis in lung..
Chitinase-3-like protein 1, also called CHI3L1 or YKL-40 is a secreted glycoprotein that is approximately 40kDa in size that in humans is encoded by the CHI3L1 gene. This gene is mapped to 1q32.1. Chitinases catalyze the hydrolysis of chitin, which is an abundant glycopolymer found in insect exoskeletons and fungal cell walls. The glycoside hydrolase 18 family of chitinases includes eight human family members. This gene encodes a glycoprotein member of the glycosyl hydrolase 18 family. The protein lacks chitinase activity and is secreted by activated macrophages, chondrocytes, neutrophils and synovial cells. The protein is thought to play a role in the process of inflammation and tissue remodeling.