β2 integrins have also a role in firm adhesion and crawling of Th1 lymphocytes on the BBB in in vitro models, whereas LFA-1 expression on human Th17 cells has a critical contribution to transmigration across interferon (IFN)-γ activated BBB, suggesting that both VLA-4 and LFA-1 integrins control Th lymphocyte trafficking into the brain in MS (Kebir et al., 2009; Steiner et al., 2010). Here, IFNG is linked to myeloid sarcoma.