Serum samples were analysed for interleukin-2 receptors levels (sIL-2R) in 26 patients with definite multiple sclerosis as defined by Poser and col. Three groups of patients form the basis of this study: group I, with 14 patients with clinical evidence of active disease; group II, with 12 patients with clinically stable multiple sclerosis; and group III, with 8 patients with other neurological diseases. Blood was collected by venipuncture and centrifuged. All samples were stored at -20°C until testing. The assay used monoclonal antibodies against epitopes of interleukin-2 receptors. In the wells of a microtiter plate coated with anti-soluble interleukin-2 receptors (Immunotech SA) samples to be measured or standards are incubated in the presence of a second monoclonal antibody conjugated with alkaline phosphatase. The amount of bound enzyme-conjugate is measured by adding a chromogenic substrate. The intensity of the resulting colour is proportional to the sIL-2R concentration present in the sample. Increased serum levels of sIL-2R were found in 7 of 14 patients with active multiple sclerosis (50%), in only 1 of the 12 patients with clinically stable multiple sclerosis and in none of the patients with other neurological diseases.
multiple sclerosis; active disease; soluble interleukin-2 receptors