Cerebrospinal hepatocyte growth factor levels correlate negatively with disease activity in multiple sclerosis.

The hepatocyte growth factor (HGF) is a pleiotropic cytokine with neuroprotective and anti-inflammatory properties. Additionally, it enhances axonal outgrowth and oligodendroglial maturation. We studied the expression of HGF by cells derived from cerebrospinal fluid (CSF), quantified HGF in CSF samples and investigated the glial expression of HGF in vitro. We found decreased expression of HGF in CSF cells as well as reduced CSF but not plasma HGF protein levels in MS. MS patients with active disease had lower HGF CSF levels than inactive MS patients, and treatment with Natalizumab correlated with increased CSF concentration of HGF. In vitro, glial production of HGF was reduced by CSF from MS patients in comparison with CSF from controls. CSF levels of CCL2, a known inducer of HGF, also correlated strongly with HGF levels. We conclude that the expression of HGF within the CNS is reflective of disease activity in MS and this may be due to decreased induction of HGF by CCL2. Furthermore, the decreased HGF associated with active disease may potentially contribute to reduced stimulation for remyelination and the occurrence of shadow plaques frequently seen in MS patients. Our results merit further validation to establish whether CSF HGF is a biomarker for MS disease activity.

Inhibition of SLPI ameliorates disease activity in experimental autoimmune encephalomyelitis.

BACKGROUND: The secretory leukocyte protease inhibitor (SLPI) exerts wide ranging effects on inflammatory pathways and is upregulated in EAE but the biological role of SLPI in EAE, an animal model of multiple sclerosis is unknown METHODS: To investigate the pathophysiological effects of SLPI within EAE, we induced SLPI-neutralizing antibodies in mice and rats to determine the clinical severity of the disease. In addition we studied the effects of SLPI on the anti-inflammatory cytokine TGF-ß. RESULTS: The induction of SLPI neutralizing antibodies resulted in a milder disease course in mouse and rat EAE. SLPI neutralization was associated with increased serum levels of TGF-ß and increased numbers of FoxP3+ CD4+ T cells in lymph nodes. In vitro, the addition of SLPI significantly decreased the number of functional FoxP3+ CD25(hi) CD4+ regulatory T cells in cultures of naive human CD4+ T cells. Adding recombinant TGF-ß to SLPI-treated human T cell cultures neutralized SLPI's inhibitory effect on regulatory T cell differentiation. CONCLUSION: In EAE, SLPI exerts potent pro-inflammatory actions by modulation of T-cell activity and its neutralization may be beneficial for the disease.

Detection of adiponectin in cerebrospinal fluid in humans.

Adiponectin circulates in the body in high concentrations, and 100-fold lower amounts were described in the cerebrospinal fluid (CSF) of mice, whereas in humans, contradictory results have been published. To clarify whether adiponectin is present in human CSF and is derived from the circulation, it was determined in human CSF and plasma of 52 nonselected patients. Adiponectin was detected by immunoblot in CSF and was quantified in CSF and serum by ELISA. CSF adiponectin was positively correlated to systemic levels, and the CSF/serum adiponectin ratio was correlated to the CSF/serum albumin ratio. Furthermore, disturbed function of the blood-brain barrier (BBB) was associated with an elevated CSF/serum adiponectin ratio. Adiponectin mRNA was not found in the brain, indicating that adiponectin crosses the BBB and/or the blood-cerebrospinal fluid barrier (BCB). Rat adiponectin with a COOH-terminal tag was injected into the tail vein of rats and was detected 3 h later in CSF. However, CSF adiponectin in humans and rats was approximately 0.1% of the serum concentration and therefore was below the 0.5% expected in the CSF because of the residual leakage of an undisturbed BBB/BCB. Taken together, data from the present study show that adiponectin in human CSF is far below the level expected by the baseline BBB/BCB permeability, indicating that adiponectin enters the brain much less efficiently than albumin, thus supporting recent data that exclude adiponectin transport to the CSF. Additional studies are needed to reveal whether these low levels of adiponectin in CSF have a physiological function.