Dopaminergic modulation of CD4+CD25(high) regulatory T lymphocytes in multiple sclerosis patients during interferon-ß therapy.

OBJECTIVE: We investigated dopaminergic inhibition of CD4+CD25(high) regulatory T lymphocytes (Treg) in relapsing-remitting multiple sclerosis (MS) patients treated with interferon (IFN)-ß. METHODS: MS patients were prospectively studied at baseline and during 1 year of IFN-ß, and compared with healthy controls (HCs). Treg were separated by immunomagnetic sorting and the effect of dopamine (DA) on Treg was assessed in coculture experiments with homologous effector T lymphocytes (Teff). Tyrosine hydroxylase (TH), dopaminergic receptors (DR) D3 and D5, and forkhead box protein P3 (FoxP3) mRNA were assessed by real-time PCR. Circulating CD4+ T cell subsets were assessed by flow cytometry. RESULTS: In coculture experiments, Treg inhibition of Teff proliferation was reduced by DA in HCs and completely abolished in MS patients at baseline. However, in patients after 12 months of IFN-ß, Teff proliferation was impaired and DA had no more effect on Treg. In comparison to cells from HCs, Treg from MS patients at baseline had increased mRNA for DR D5 and TH (but not for DR D3). During treatment with IFN-ß, both DR D5 and TH mRNA decreased down to values lower than those of cells from HCs. In comparison to HCs, MS patients had a higher frequency of circulating Treg, both at baseline and after IFN-ß, while FoxP3 mRNA levels in Treg were similar in patients and HCs and did not show major changes during IFN-ß. CONCLUSIONS: Dopaminergic inhibition of Treg in MS patients is suppressed during IFN-ß treatment. Treg play a key role in the suppression of autoimmunity, thus the effect may have a therapeutic repercussion.

Serum levels of N-acetyl-aspartate in migraine and tension-type headache.

Serum levels of N-acetyl-aspartate (NAA) may be considered a useful marker of neuronal functioning. We aimed to measure serum NAA in cohorts of migraine and tension-type headache patients versus controls, performing correlations with main clinical features. A total of 147 migraine patients (including migraine without aura, with aura and chronic migraine), 65 tension-type headache (including chronic and frequent episodic tension-type headache) and 34 sex- and age-matched controls were selected. Serum was stored at -80 °C. Quantification of NAA was achieved by the standard addition approach and analysis was performed with liquid-chromatography-mass-spectrometry (LC/MS) technique. The NAA levels were significantly decreased in migraine group (0.065 ± 0.019 mol/L), compared with both tension-type headache patients (0.078 ± 0.016 mol/L) and controls (0.085 ± 0.013 mol/L). Control subjects were significantly different from migraine with and without aura and chronic migraine, who differed significantly from episodic and chronic tension-type headache. Migraine with aura patients showed lower NAA levels when compared to all the other headache subtypes, including migraine without aura and chronic migraine. In the migraine group, no significant correlation was found between NAA serum levels, and headache frequency, allodynia and interval from the last and the next attack. The low NAA in the serum may be a sign of neuronal dysfunction predisposing to migraine, probably based on reduced mitochondria function.

Combination treatment of Glatiramer Acetate and Minocycline affects phenotype expression of blood monocyte-derived dendritic cells in Multiple Sclerosis patients.

The effects of Glatiramer Acetate (GA) in combination with Minocycline (MIN), a second-generation tetracycline, have been investigated on the course of EAE in mice, resulting in a significant reduction in disease severity and burden with attenuation of the inflammation, axonal loss and demyelination. Here we investigate the effects of combination therapy with GA and MIN on the induction, maturation and phenotyping of blood monocyte-derived dendritic cells (DCs) in Multiple Sclerosis (MS) patients. Hence the expressions of HLA-DR, CD11c, CD83 and CD1a were studied by flow cytometric analysis on immature (iDCs) and mature DCs (mDCs) from untreated and GA treated MS patients. Thirteen relapsing-remitting MS patients and 13 healthy controls (HCs) were included in the study. Ten of the MS patient group were re-tested after a 2 month period of GA treatment. The marker expressions on DC from untreated MS and HCs were studied in vitro in the absence or presence of GA and GA+MIN; and on DCs from GA treated MS patients without and with the in vitro addition of MIN. We found that in vitro GA alone or in combination with MIN downregulated DCs antigen presentation capability (HLA-DR), whereas the combination treatment only affected also myeloid DCs activation (CD83) in both MS and HCs. Prolonged GA treatment (in vivo for 2 months) affected antigen presentation capability by DCs, whereas when treated in vitro with MIN these cells also tended to reduce activation marker expression and myeloid phenotype acquisition (CD11c). The present data demonstrate possible combination effects of GA and MIN on peripheral blood monocyte-derived DCs in MS patients.