LAG-3 KO Treg suppress homeostatic proliferation, but LAG-3 KO responders are resistant to suppression.

<p>A) WT or LAG-3 KO Treg were transferred into RAG KO mice at a ratio of 1∶4 with WT responders. Responders alone received 4E6 WT Tresp with no Treg. B) WT or LAG-3 KO Treg were transferred into RAG KO mice at a ratio of 1∶4 with KO responders. Responders alone received 4E6 LAG3 KO Tresp with no Treg. C) Representative plots of FOXP3 expression in adoptively transferred cells. D) Summary of FOXP3 expression in adoptively transferred cells (n = 4). E) CD25 MFI expression on Treg with either WT or LAG-3 KO Responders. F) WT or LAG-3 KO CD4 Tresp were mixed at a 4∶1 ratio with FOXP3 GFP Treg, stimulated with CD3/CD28, and pulsed with H3-Thymadine after 72 hours. Total CPM counts are shown. Baseline activation of WT or LAG-3 KO Tresp without Treg was not different and is reported by a dashed line. Data shown are representative of at least two independent experiments with n = 4–5 mice per group.