Tumor necrosis factor-alfa and interleukin-4 in cerbrospinal fluid and plasma in different clinical forms of multiple...

Multiple sclerosis (MS) is an immune-mediated central nervous system disease characterized by inflammation, demyelination and axonal degeneration. Cytokines are proven mediators of immunological process in MS. The aim of this study was to investigate whether there is a difference in the production of the tumor necrosis factor alpha (TNF-alpha) and interleukin-4 (IL-4) in cerebrospinal fluid (CSF) and plasma in the MS patients and the controls (other neurological non-inflammatory diseases) and to determine a possible difference in these cytokines in plasma and CSF in different clinical forms of MS.

This study involved 60 consecutive MS patients--48 patients with relapsing-remitting MS (RRMS) and 12 patients with secondary progressive MS (SPMS). The control group consisted of 20, age and sex matched, non-immunological, neurological patients. According to the clinical presentation of MS at the time of this investigation, 34 (56.7%) patients had relapse (RRMS), 14 (23.3%) were in remission (RRMS), while the rest of the patients, 12 (20.0%), were SPMS. TNF-alpha and IL-4 concentrations were measured in the same time in CSF and plasma in the MS patients and the controls. Extended disability status score (EDSS), albumin ratio and IgG index were determined in all MS patients.

The MS patients had significantly higher CSF and plasma levels of TNF-alpha than the controls (p < 0.001 for both samples). IL-4 CSF levels were significantly lower in the MS patients than in the controls (p < 0.001), however plasma levels were similar. The patients in relapse (RRMS) and with progressive disease (SPMS) had higher concentrations of CSF TNF-alpha levels than the patients in remission (p < 0.001). IL-4 CSF levels in relapse (RRMS) and SPMS groups were lower than in the patients in remission. The patients in remission had an unmeasurable plasma TNF-alpha level and the patients with SPMS had significantly lower IL-4 levels in plasma than the patients in relapse and remission (p < 0.001). The only significant correlation between cytokine level with either EDSS, or albumin ratio, or IgG index, was found between CSF TNF-alpha levels and albumin ratio in the patients with relapse (R square = 0.431, p < 0.001).

According to the obtained data MS relapse was characterized by high concentrations of TNF-alpha in CSF and plasma and low concentrations of IL-4 in CSF. Remission was characterized by high concentrations of IL-4 and low concentrations of TNF-alpha both in CSF and plasma. SPMS was characterized with lower concentrations of TNF-alpha and IL-4 compared to relapse, both in CSF and plasma.