Impaired lymphocyte egress in Lyve-1 Cre Sphk-deficient mice. (A–E) Cell numbers in the indicated fluids and tissues in Lyve-1 Cre⁺ Sphk-deficient and control mice. The LN count was from a pool of two axillary, brachial, and inguinal LNs. Enumerated CD4⁺, CD8⁺, and CD19⁺ cells were CD62L^hi. Points indicate data from individual mice, and white (control mice) and black (Sphk-deficient mice) bars represent means. (F) S1P1 on CD4⁺ CD62L^hi T cells from the indicated tissues. Shaded histograms show staining with control antibody. The vertical dashed lines mark the peak S1P1 intensity in the LN sample to allow comparison. Data in A–F are representative of at least three experiments with one to two mice per experiment. (G and H) Immunohistochemial analysis of LNs (G) and Peyer's patches (H) stained for LYVE-1 (brown) and CD3 (blue) or B220 (blue).