Fig. 5.

Reduced number and activation of T cells in the periphery and early onset of colitis in cDKO mice. (A) CD4⁺ and CD8⁺ T cell numbers in spleens of cDKO mice are significantly reduced. Bars represent average of absolute lymphocyte numbers (±SD) (n = 4–6 mice per group). *, P < 0.01 compared with WT and WKO. (B) T cells purified from lymph nodes of WKO and cDKO mice show marked decrease in proliferative response to anti-CD3 plus IL-2 stimulation. Bars indicate mean values of cpm ([³H]thymidine) ± SD of triplicate wells from one of four experiments. *, P < 0.01 compared with WT. (C) Antigen-receptor-induced spreading is markedly decreased in WKO and cDKO peripheral T cells. Bar graphs show the average of relative numbers of spread T cells from triplicate samples (±SD) representative of three experiments. *, P < 0.01 compared with WT. (D) CCL19-induced chemotaxis of peripheral T cells is significantly diminished in both WKO and cDKO mice. Data are shown as average ± SD of triplicates from one of two experiments. (E) Histological analyses of distal colons show signs of severe inflammation with crypt elongation and mucosal thickening in samples from cDKO mice. Age-matched (2 months) WT and WKO mice show no sign of colitis in this representative experiment.