MS-related material in blood of multiple sclerosis patients: results with the leucocyte adherence inhibition assay.

To determine the value of laboratory methods proposed as tests for multiple sclerosis (MS), the reactivity of leucocytes to a preparation of an antigen from the blood of patients with MS (MS-related material) was studied in the leucocyte adherence inhibition (LAI) test. The results point to the existence of an antigenic substance in the blood of MS patients. When the LAI test was modified by the addition of calf serum there was a significant reaction of the leucocytes of MS compared to other neurological diseases and controls. The relatively high positive rate in MS previously reported was not detected. Therefore, further analyses concerning the characterisation of the antigen and the conditions of the test system will be necessary before the method can be used for diagnosis.