How does natalizumab inhibit immune-cell migration into inflamed brain tissue in multiple sclerosis?

Natalizumab binds leukocyte α4β1 integrin and blocks its interactions with VCAM‑1, CS‑1 and osteopontin, inhibiting firm adhesion and migration across the blood–brain barrier into inflamed brain tissue, thereby reducing inflammation and further immune-cell recruitment in multiple sclerosis.