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 patients, CSF LCN2 levels correlated with basal ganglia iron accumulation (r = 0.5, p < 0.05). In CIS, higher CSF LCN2 levels were associated with conversion to clinically definite MS (p < 0.05).
Conclusion: We demonstrate altered LCN2 regulation in early MS and provide first evidence for this to be possibly linked to both clinical MS activity and iron accumulation in the basal ganglia.
Keywords: 3T MRI; Lipocalin 2; biomarker; brain iron; cerebrospinal fluid; clinically isolated syndrome; multiple sclerosis.
© The Author(s), 2016.