What Is Natalizumab Used For?
How Does It Work?An antibody (also known as an immunoglobulin) is a protein made by the immune system. Antibodies bind to substances in the body called antigens. Natalizumab is an anti-alpha-4-integrin antibody. This means it binds to and blocks alpha-4-integrin.
Apha-4-integrins are molecules found on most white blood cells (immune cells). They help white blood cells bind to other cells. When white blood cells bind to certain other cells in blood vessels near the brain, the white blood cells can get into the brain, where they can damage myelin. When white blood cells bind to certain cells in the gastrointestinal tract, they may cause inflammation.
The exact way natalizumab works for MS and Crohn's disease is not entirely known. It is believed that by blocking alpha-4-integrin, natalizumab prevents white blood cells from binding to other cells. This prevents white blood cells from getting into the brain and attacking nerves (which can help with MS) and from causing inflammation in the gastrointestinal tract, which can help with Crohn's disease.