Ingested (oral) tocilizumab inhibits EAE

Background: Blocking the activity of IL-6 can inhibit autoimmune diseases such as rheumatoid arthritis and Crohn's disease. Objective: We examined whether an antibody against IL-6, tocilizumab (TCZ) (Actemre (R)), used clinically in rheumatoid arthritis (RA) would have similar anti-inflammatory effects in EAE after oral administration. Design/method: B6 mice were immunized with MOG peptide 35-55 and gavaged with control saline or TCZ during ongoing disease. Splenocytes, CD4(+) T cells or macrophages/monocyte lineage cells (CD11b(+)) from control fed or TCZ fed mice were adoptively transferred into active MOG peptide 35-55 immunized recipient mice during ongoing disease. Actively fed and recipient mice were examined for disease inhibition, inflammation, and cytokine responses. Results: Ingested (oral) TCZ inhibited ongoing disease and decreased inflammation. Adoptively transferred cells from TCZ fed donors protected against actively induced disease and decreased inflammation. There was a decrease in IL-6 in actively treated spleen, decrease in TNF-alpha, Th1-like cytokine IL-12 and increase in Th2-like cytokine IL-10 in active fed and adoptively treated recipients. Conclusions: Ingested (orally administered) TCZ can inhibit disease, CNS inflammation, decrease pro-inflammatory Th1-like cytokines and increase Th2-like anti-inflammatory cytokines. (C) 2014 Elsevier Ltd. All rights reserved.