CXCR5 and functional LFA-1 control B cell speed but are dispensable for B-cell guidance by the stromal network. (A) Speeds of WT and CXCR5^−/− B cells in T-cell area and B-cell follicle of FD441.8-treated PLNs. Each dot represents an individual track. The red bar represents the mean. Data in A are from 3 mice, 3 image sequences, and 534 WT and 227 CXCR5^−/− B-cell tracks. (B) Speeds of WT and CXCR5^−/− B cells in T-cell area and B-cell follicle of FD441.8-, PS/2-, and NIBR1816-treated plt/plt PLNs. Each dot represents an individual track. The red bar represents the mean. Data in B are from 2 mice, 5 image sequences, and 773 WT and 155 CXCR5^−/− B cell tracks. (C) Example of 2-P microscopy images at indicated times post B-cell transfer. WT and CXCR5^−/− B cells with or without FD441.8 treatment migrate in close association with GFP fibers of the T-cell area. The tracks are represented by the dotted line in each frame. Scale bar, 10 µm. (D) Percentage of motile B cell turn of WT and CXCR5^−/− B cells in T-cell area and WT B cell in B-cell follicle with and without FD441.8 treatment. Data are pooled from 29 to 63 individual cell tracks. **P < .01. n.s., not significant.