β₂ integrins LFA-1 and Mac-1 are expressed at high levels on neutrophils, where they mediate important functions in neutrophil recruitment. Ly6G, a GPI-linked protein, is also present at high levels on the neutrophil surface, although its function is unknown. Wang et al show that Ly6G is co-localized with β₂ integrins, and that antibody ligation of Ly6G reduces β₂ integrin expression and inhibits neutrophil recruitment. The existence of an endogenous ligand for Ly6G is yet to be demonstrated. Professional illustration by Kenneth X. Probst.