Anti-YKL-40/CHI3L1 Antibody Picoband® Fluoro488 Conjugated

Chitinase-3-like protein 1 (CHI3L1), also known as YKL-40, is a secreted glycoprotein that is approximately 40kDa in size that in humans is encoded by the CHI3L1 gene. 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.

Detected in lung in pulmonary macrophages and alveolar type 2 cells and in bronchoalveolar lavage (BAL) fluids. Expressed in mammary tumor cells (at protein level) . Expressed in lung. Not detected in non-inflammatory colon.

Carbohydrate-binding lectin with a preference for chitin. Has no chitinase activity. May play a role in tissue remodeling and in the capacity of cells to respond to and cope with changes in their environment. Plays a role in T-helper cell type 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 colonic mucosa and lymphoid organs. Mediates activation of AKT1 signaling pathway and subsequent IL8 production in colonic epithelial cells. Regulates antibacterial responses in lung by contributing to macrophage bacterial killing, controlling bacterial dissemination and augmenting host tolerance. Also regulates hyperoxia-induced injury, inflammation and epithelial apoptosis in lung.

1. Chung, C., Tallerico, T., Seeman, P. Schizophrenia hippocampus has elevated expression of chondrex glycoprotein gene. Synapse 50: 29-34, 2003. 2. Hakala, B. E., White, C., Recklies, A. D. Human cartilage gp-39, a major secretory product of articular chondrocytes and synovial cells, is a mammalian member of a chitinase protein family. J. Biol. Chem. 268: 25803-25810, 1993. 3. Ober, C., Tan, Z., Sun, Y., Possick, J. D., Pan, L., Nicolae, R., Radford, S., Parry, R. R., Heinzmann, A., Deichmann, K. A., Lester, L. A., Gern, J. E., Lemanske, R. F., Jr., Nicolae, D. L., Elias, J. A., Chupp, G. L. Effect of variation in CHI3L1 on serum YKL-40 level, risk of asthma, and lung function. New Eng. J. Med. 358: 1682-1691, 2008.

Secreted, extracellular space. Cytoplasm. Endoplasmic reticulum. Detected in bronchoalveolar lavage (BAL) fluids. Localizes mainly to endoplasmic reticulum when overexpressed in cells, with some protein also detected throughout the cytoplasm.