Changes in the Immunological Profile of Peripheral Blood Leukocytes in Multiple Sclerosis (MS) Patients Treated with lnterferon-ß-1 a. Veränderungen des immunologischen Profils von Leukozyten im peripheren Blut von Multiple-Sklerose-(MS-)Patienten, behandelt mit lnterferon-ß-1 a

Abstract

Interferon (IFN-ß) has beneficial effects in multiple sclerosis (MS) probably by regulating the immune system. The aim of this study was to find out whether IFN-ß-la influences the immune profile of peripheral blood (PB) leukocytes in MS patients. We studied 21 outpatients (12 women and nine men; mean age: 37.2 years) with relapsing-remitting MS who had been treated with IFN-ß-la (30 fig i.m. once a week) for 9 months. Phenotype analysis of PB leukocytes was carried out using two-color flow cytometry. The following antigens were determined: CD3, CD4, CDS, CD14, CD19, CD56, CD16, CD25, CD38, CD80, CD86. Blood samples were collected before IFN-ß-la administration as well as after 3, 6, and 9 months of treatment. We found a statistically significant decrease of CD19 + cells (B lymphocytes) after 3 months of IFN-ß-l.a administration. After 6 and 9 months of IFN-ß-la therapy, the percentage of CD14+CD86+ cells (monocytes with expression of costimulatory molecules) and CD3+CD25+ cells (activated T cells) increased. The percentage of CD56 + CD16 + cells (NK cells) decreased after 3, 6, and 9 months. CD14+CD86+ cells are involved in Th2 lymphocyte activation, which releases anti-inflammatory cytokines. This possibly limits myelin sheath damage resulting from inflammation. CD3 + CD25 + cells may also represent Th2 cell populations. B lymphocytes (CD19 + cells) may be responsible for the production of immunoglobulins directed against myelin components, so . Eingegangen: 28. Dezember 2000/Angehommen: 5. März 2001 that the decrease in their percentage might be due to the suspected positive action of IFN-ß-la in MS patients. Our results indicate that IFN-ß-la affects immunocompetent cell populations in MS, which may influence the clinical course of the disease.