Immunochemical monitoring of remittent and secondary-progressive course of multiple sclerosis (MS) was performed. Examination of 61 patients was performed during 3 years. Inflammatory cytokines: (IL-1, IL-2, IL-6, TNF-alpha), were measured in supernatants of the peripheral blood mononuclear cells while some neurospecific proteins (GFAP and alpha 2-GP), vesicular-cellular molecules of the adhesion (sVCAM-1) were estimated in blood serum. 50 healthy donors entered the control group. The results demonstrated a remaining functional tension of cell immunity and a decrease of the resistance of hematoencephalic barrier (HEB) at all MS stages. However, in secondary-progressive MS concentration of the sVCAM-1 in blood serum was elevated as compared with the control group, patients with remittent course and in clinical improvement. It is suggested that some functional alteration of HEB endothelium, manifest in constant pathologic expression of sVCAM-1 molecule, is one of the pathochemical mechanisms promoting progression of MS process.