Introduction: Clinical trials of patients with multiple sclerosis (MS) have produced inconsistent results for the profile of cytokine secretion in serum and cerebrospinal fluid in patients with multiple sclerosis during periods of relapse and remission. Epidemiological and clinical observations data reveal an association of the changes in vitamin D serum concentration with the risk of developing MS.
Aim: To evaluate changes in serum concentrations of 25(OH)D, IL17, IFN-gamma, TGFβ1, IL4, IL10 in relapse and remission and their correlation with the severity of disability.
Patients and methods: Fifty-three persons (30 clinically healthy controls and 23 patients with relapsing-remitting multiple sclerosis) living between 41° and 42° northern latitude were registered during the astronomical winter period (October 2012- May 2013). -Patients were diagnosed according to Mc Donald 2010 criteria. The degree of neurological deficit was assessed by EDSS. Serum concentrations of 25(OH)D (nmol/l) and cytokines (pg/ml) were tested by ELISA - once for controls and twice for patients (during relapse and remission).
Results: In the studied population average levels of 25(OH)D were close to insufficiency, most pronounced in patients in relapse, as differences were not statistically significant. A reverse correlation was found between the levels of 25(OH)D and the deficit in relapse and remission. Concentrations of TGFβ1 significantly increased in remission compared with exacerbation and controls. Serum level of IL4 was significantly lower in relapse compared with controls. In remission there was a marked tendency of increase compared with exacerbation. During clinical improvement IL17 and IFN-gamma tended to decrease compared to the average levels in relapse. In both periods, the average concentrations of IFN-gamma in patients were significantly lower compared with controls. No statistically significant differences were found comparing cytokine changes with those of 25(OH)D and deficit.
Conclusion: Persistent cytokine imbalance in patients compared with controls is a marker for Th1-mediated CNS demyelination. Anti-inflammatory TGFβ1, IL4 are indicators of immune response intensity. The deficit severity does not depend on changes of the tested cytokines, but correlates with 25(OH)D levels during periods of relapse and remission.