Rap1a and PIP5Kγ90 cooperate to induce neutrophil slow rolling and arrest. (A,C,E,G,I) Rolling velocities of neutrophils of the indicated genotype on E-selectin with or without co-immobilized ICAM-1 in the presence or absence of anti-ICAM-1 mAb. (B,D,F,H,J) Percentages of neutrophils of the indicated genotype rolling, arrested and round, or arrested and spread on co-immobilized E-selectin, ICAM-1, and CXCL1. (K) Isolated bone marrow neutrophils of the indicated genotype were incubated with or without CXCL1, lysed, and immunoprecipitated (IP) with control or anti-β2 integrin mAb. Immunoprecipitates were analyzed by immunoblotting (IB) with anti-talin or anti-β2 integrin antibodies. (L-N) Numbers of differentially labeled adherent bone marrow leukocytes from the indicated genotype in TNF-stimulated venules of cremaster muscle. In some experiments, labeled leukocytes were pretreated with PTx and then injected into TNF-challenged mice that were previously injected with PTx. (O-Q) Velocities of differentially labeled bone marrow leukocytes from mice of the indicated genotype rolling in TNF-stimulated venules of cremaster muscle, measured before and after injecting a blocking mAb to P-selectin and then a blocking mAb to β2 integrins. The labeled leukocytes were pretreated with PTx and then injected into TNF-challenged WT mice that were previously injected with PTx. The data in K are representative of 3 experiments. Other data represent the mean ± SEM from 5 experiments, with 5 mice in each experimental group. *P < .05 for rolling velocity; #P < .05 for percentage of rolling cells compared with that in WT, as determined by unpaired Student t test.