Serum of patients with multiple sclerosis induce activation of antigen presenting cells A. Karni a , D. Azulai a , A. Korczyn a and H. Weiner b a Department of Neurology, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel; b Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MS, USA Objective: To study the effect of serum from patients with multiple sclerosis (MS) on activation of antigen presenting cells (APCs).