The Chemotactic Defect in Wiskott-Aldrich Syndrome Macrophages Is Due to the Reduced Persistence of Directional Protrusions
Figure 4
WASp is required for the persistence of chemotactic protrusion in primary BMMs.
(A) The role of WASp in directional sensing was examined by monitoring the chemotactic responses of wild-type and WASp-deficient macrophages in a CSF-1 gradient. Representative kymographs from time lapse images of wild-type (WT, top panel) and WASp−/− (middle panel) BMM in response to CSF-1 containing micropipette (Movies S4 and S5) are shown. The bottom panel shows an overlay of the outlines of the membrane protrusive activities of wild-type and WASp−/− BMMs. (B) Onset, (C) duration, (D) maximum length and (E) protrusion rate (maximum length/time it takes the protrusion to reach maximum length) after CSF-1 stimulation were determined. The data represent the mean of at least 30 cells from each cell type over a minimum ten separate videos. Error bars represent SEM. * p<0.05, ***p<0.001.