A longitudinal study on IL-2, sIL-2R, IL-4 and IFN-gamma in multiple sclerosis CSF and serum

The cerebrospinal fluid (CSF) and serum levels of interleukin-2 (IL-2), soluble IL-2 receptor (sIL-2R), interleukin-4 (IL-4) and interferon-gamma (IFN-gamma) were longitudinally investigated in 20 multiple sclerosis (MS) patients. There were 80 paired CSF and serum samples (range 2-8 per patient) covering a 1-5 year (mean 2.5 year) period. Increased levels of IL-2 and sIL-2R were found in 56 and 71%, respectively, of MS sera. In all patients, one or several sera (totally 89%) exhibited values above the normal range for either one of the components or both. The occurrence of IL-2 or sIL-2R positive CSF specimens was much lower, 15 and 9%, respectively. Only 3 MS sera (from one patient) had clearly detectable IL-4 and no CSF samples were definitely positive. IFN-gamma was undetectable in all serum and CSF specimens. No correlations were found between the immunological parameters and the clinical disease activity. The cytokine patterns in MS give strong support for the presence of a systemic T-cell activation. Furthermore, the data argue for a predominant activation of an IL-2- and sIL-2R-producing but not IL-4-producing T-helper (Th) lymphocyte subpopulation, Th1/CD4 + CD45R + cells.