Effect of reducing L-selectin levels on lymphocyte trafficking to PLNs. (A) Expression of L-selectin on WT, L^+/- (L-selectin^+/-), and L^-/- T and B cells. n = 3 mice per group. (inset) Histogram depicting L-selectin mean fluorescence intensity (MFI) of WT T cells (T^+/+, thick solid line), WT B cells (B^+/+, solid grey line), L^+/- (T^+/-), and L^-/- (T^-/-) T cells (solid lines). (B) One-hour homing of T cells (i) and B cells (ii) to WT and C2GlcNAcT-I^-/- PLNs. For T cells, 1-way ANOVA with Bonferroni multiple comparison test revealed statistical significance (P < .05) between L^+/+ cells in WT mice and L^+/- cells in C2^-/- mice. For B cells, 1-way ANOVA with Bonferroni multiple comparison test revealed statistical significance between L^+/+ cells in WT mice and L^+/- cells in WT mice (P < .05), L^+/+ cells in WT mice and L^+/+ cells in C2^-/- mice (P < .01), and L^+/+ cells in WT mice and L^+/- cells in C2^-/- mice (P < .01). When separate 2-group comparisons were performed using multiple unpaired 2-tailed Student t test, L^+/-, T- and B-cell homing to WT PLNs was significantly different from that of all other groups (P < .05), except for L^+/+ homing to C2^-/- PLNs. n = 5 mice per group. Rolling fraction (C) and sticking efficiency (D) of L^+/- T cells in WT and C2GlcNAcT-I^-/- PLN venules. WT: n = 2 mice (order I, n = 1 venule; order II, 1; order III, 3; order IV, 6; order V, 5). C2GlcNAcT-I^-/-: n = 4 mice (order I, 3 venules; order II, 4; order III, 8; order IV, 9; order V, 2). ^*P < .05, and ^***P < .0001 compared with WT. (E-F) Rolling velocities of L^+/- T cells in order III (E) and order IV (F) venules WT and C2GlcNAcT-I^-/- PLN.