Increased brain-derived neurotrophic factor expression in white blood cells of relapsing-remitting multiple sclerosis patients

Central nervous system (CNS)-autoreactive immune responses can exert neuroprotective effects, possibly mediated via the release of neurotrophic factors from infiltrating leucocytes. Herein, we analysed neurotrophin and cytokine mRNA levels using TaqMan polymerase chain reaction in unstimulated peripheral blood mononuclear cells (PBMCs) from multiple sclerosis (MS) patients in remission and controls. We demonstrate that mRNA for brain-derived neurotrophic factor (BDNF), but not neurotrophin-3 or nerve growth factor (NGF), is readily detectable in PBMC and that levels in MS are increased by approximately 60% compared with patients with other neurological diseases or healthy subjects. These results provide additional evidence that a potentially neuroprotective facet of autoimmune inflammation is present in MS.