Multiple sclerosis: prospective analysis of TNF-alpha and 55 kDa TNF receptor in CSF and serum in correlation with clinical and MRI activity.

The possibility of antagonizing tumor necrosis factor-alpha (TNF-alpha) in vivo with antibodies or soluble TNF receptor has focused much interest on the role of this cytokine in the natural course of MS. We studied nine patients prospectively and serially for one year (14 time points, 131 observations). TNF-alpha and the 55 kDa soluble TNF receptor were measured every 4 weeks in the serum and at defined time points in the CSF. Each value was correlated to clinical symptoms and to MRI measurements obtained on the same day. All patients with relapsing-remitting disease showed periodic increases of TNF concentrations. Overall, the association between serum TNF-alpha levels and bursts of Gd-DTPA enhancement on cranial MRI was not sufficiently tight to reach statistical significance. However, serum TNF levels > 50 pg/ml and measurable CSF levels were always associated with Gd-DTPA enhancing MRI lesions. Isolated high serum TNF peaks were noted during episodes of infection, hay fever or psychic stress. After treatment with glucocorticoids, TNF levels were suppressed for several months, whereas new Gd-DTPA enhancing lesions continued to appear. The concentrations of the soluble 55 kDa TNF receptor did not show marked fluctuations. These results are consistent with an active role of TNF-alpha in MS during periods of disease activity and provide further support for the clinical evaluation of anti-TNF therapies.