The levels of sIL-2R alpha, sICAM-1, and sVCAM-1 in sera of patients with clinically probable multiple sclerosis (ms) during the first relapse were assessed. In ms patients the levels of these 3 soluble molecules were significantly increased in comparison with the results obtained in controls. The results reflected activation of lymphocytes T and enhancement expression of adhesion molecules on brain endothelial cells, therefore they could serve indirectly as markers of immunological activation in multiple sclerosis. Any of the levels of soluble molecules in sera did not correlate with the severity of the disease.