Natalizumab alters transcriptional expression profiles of blood cell subpopulations of multiple sclerosis patients.

Natalizumab, the most recently approved treatment for relapsing multiple sclerosis (MS) exerts its action through binding to alpha4 integrins. We studied longitudinally gene expression profiles in peripheral blood of MS patients, treated with natalizumab for more than 2 years. The majority of altered genes relates to immune response, signal transduction, adhesion and metabolism. Not only gene expression relevant for T lymphocytes was altered, but also genes regulating B-lymphocyte, neutrophil and erythrocyte functions. Understanding these different gene effects and their interrelationships will provide more insights into additional mechanisms of action of natalizumab and possibly allow better prediction of adverse events.