Therapeutic apheresis combined with pulse therapy with small doses of corticosteroids was used in 7 patients with secondary progressing multiple sclerosis (MS) during 4 years. Before perfusions, we investigated the lymphocyte sensitivity to methylprednisolone in vitro in the reaction of leukocyte migration with myelin basic protein in each patient. The introduction of test doses of corticosteroids in each patient's blood sample before perfusion procedures showed the different rate of leukocyte migration with the myelin basic protein. On this basis, we selected an individual optimal methylprednisolone dose that was infused intravenously just after each perfusion procedure. The number of patients sensitive to low doses of methylprednisolone increased after therapeutic apheresis. These findings allow to consider the reaction of leukocyte migration with the presence of myelin basic protein as a new method of individual selection of corticosteroid doses for increase of treatment efficacy of secondary progressing multiple sclerosis.