Increases of gut-homing receptor expressing CD4⁺ T cells in hemophilia B mice. (A) Representative examples of flow cytometric analysis of CCR9 and integrin α4β7 staining. Frequencies of CCR9 (B) and α4β7 (C) expressing cells in the spleen, MLNs, and PPs following oral delivery of FIX plant material and IV challenge with FIX. Control groups were fed with WT plant material (wt fed) or with FIX material but not challenged with IV injections of FIX (FIX fed no injection). Data points are for individual mice, with average ± SEM also indicated (n = 4-6 per group).