Cerebrospinal fluid lipocalin 2 in patients with clinically isolated syndromes and early multiple sclerosis

Background:Lipocalin 2 (LCN2) may be involved in the immunopathogenesis of multiple sclerosis (MS) and might further impact on iron homoeostasis. Brain iron accumulates in MS; however, the association to iron-related proteins is still unsolved.Objective:To investigate cerebrospinal fluid (CSF) and serum LCN2, transferrin (Trf) and ferritin in early MS in relation to disease evolution and longitudinal brain iron accumulation.Methods:We analysed CSF and serum LCN2 by enzyme-linked immunosorbent assay (ELISA) and Trf and ferritin by nephelometry in 55 patients (45 clinically isolated syndrome (CIS), 10 MS, median clinical follow-up 4.8 years) and 63 controls. In patients, we assessed sub-cortical grey matter iron by 3T magnetic resonance imaging (MRI) R2* relaxometry (median imaging follow-up 2.2 years).Results:Compared to controls serum (p < 0.01), CSF (p < 0.001) LCN2 and CSF Trf (p < 0.001) levels were reduced in the patients. CSF LCN2 correlated with CSF Trf (r = 0.5, p < 0.001). In clinically stable pat...