Interferon-β induces brain-derived neurotrophic factor in peripheral blood mononuclear cells of multiple sclerosis patients

Interferon-β (IFN-β) achieves its beneficial effect on multiple sclerosis (MS) via anti-inflammatory properties. In this study, we assessed the expression of the brain-derived neurotrophic factor (BDNF) in peripheral blood mononuclear cells (PBMC) from relapsing–remitting multiple sclerosis (RRMS) patients treated or not with IFN-β. Intracellular BDNF was measured by Western blot and ELISA and compared with serum BDNF. We found higher levels of BDNF in PBMC of IFN-β-treated versus non-treated patients, whereas serum levels of BDNF were similar. We hypothesize that the increased intracellular BDNF secondary to IFN-β is not released in the periphery. This release is probably not tissue specific but in MS patients, BDNF could be specifically delivered by PBMC at the site of re-activation, i.e. within the central nervous system.