Second, it reframes integrin signaling in MS: while α4 integrins have long been established as central to lymphocyte trafficking across the BBB [23] and serve as therapeutic targets for NAT, our findings suggest that ITGB3 could represent an alternative or complementary immune checkpoint integrin modulating peripheral immune activity, BBB dynamics, and disease progression. Here, ITGB3 is linked to myeloid sarcoma.