Burman J, Raininko R, Blennow K, Zetterberg H, Axelsson M, Malmeström C. YKL-40 is a CSF biomarker of intrathecal inflammation in secondary progressive multiple sclerosis.J Neuroimmunol. 2016;292:52-7.
YKL-40 (CHI3L1) is a glycoprotein predominantly produced by reactive astrocytes in chronic active MS lesions, which are common in secondary progressive MS. In this study, YKL-40 was investigated in different stages of MS and in relation to MRI findings. YKL-40 levels in CSF samples from two independent patient cohorts of MS patients were determined with ELISA. CSF YKL-40 was increased in patients with active relapsing-remitting MS and correlated with the number of gadolinium enhancing lesions. Patients with secondary progressive MS had similar high levels of YKL-40, whereas not active relapsing-remitting MS patients had YKL-40 levels comparable to healthy controls.
Chitinase-3-like protein 1 (CHI3L1), also known as YKL-40, is a secreted glycoprotein. The name YKL-40 is derived from the three N-terminal amino acids present on the secreted form and its molecular mass. YKL-40 is secreted by various cell-types including macrophages, and chondrocytes, YKL-40 lacks chitinase activity due to mutations within the active site (conserved sequence: DXXDXDXE ; YKL-40 sequence: DGLDLAWL). The exact physiological role of YKL-40 is not known, but it has been implicated in development, inflammatory disease .
You may remember the post last week by NDG on Chiti What so yet another study suggesting that chininase is a biomarker of something.It sis suggested that is is a marker of active inflammation in MS, but what is it doing in secondary progressive MS where we believe in many cases inflammation is not active. The best surrogate we have at present foractive inflammation