Microvascular permeability changes in cremasteric venules of chimeric mice (Lsp1^−/− into WT and WT into Lsp1^−/−). Measurements were taken after KC superfusion of the cremaster muscle preparation. Besides equal rolling flux (A) and adhesion (B), WT into LSP-1 deficient animals (lacking LSP1 only in the endothelium) show impaired neutrophil transmigration (C) and increased microvascular leakiness (D) compared with Lsp1^−/− into WT animals (lacking LSP1 only in the neutrophils). Depletion of neutrophils with anti Gr-1 Ab injection 24 hours before experiments shows a return of permeability to baseline levels (E). The amount of permeability normalized for number of emigrated neutrophils as shown 60 minutes after KC superfusion (F). Each group contained at least 3 animals. *P < .05; **P < .01; ***P < .001. Error bars indicate SEM.