Fig. 7.
pTregs suppress autologous T cell responses in vivo. (A and B) Comparison of induction of lymphoproliferative disorder in SPF or GF Rag1−/− hosts upon transfer of 1 × 106 CD44lo CD62Lhi naive CD4 T cells from CD45.1 Foxp3-GFP mice. (A) H&E staining of sections of liver and colon at day 21 after injection (n = 4 per each). Scale bars, 100 μm. The arrows indicate lymphocyte infiltrations. (B) Graph for weight change percentages of SPF or GF Rag1−/− hosts after transfer of indicated T cell populations. SPF and GF Rag1−/− hosts (n = 2–3) were injected with naive CD4 T cells (1 × 106) alone or a mixture of naive CD4 T cells (1 × 106) and purified Tregs (2 × 105). (C) Percentages of Foxp3+ cells among donor T cells at day 7 (n = 4) or day 21 (n = 4) in the GF Rag1−/− hosts injected with 1 × 106 CD44lo CD62Lhi naive CD4 T cells from CD45.1 Foxp3-GFP mice. (D and E) Effect of depleting pTregs in GF Rag1−/− hosts adoptively transferred with 1 × 106 CD44lo CD62Lhi naive CD4 T cells from Foxp3-DTR mice. Host mice were analyzed at 1 wk (n = 3), 2 wk (n = 3), or 4 wk (n = 2) posttransfer. Where indicated, DT was administered during the last week (n = 3). (D) Shown are total donor T cell numbers in spleen. (E) H&E staining of liver, with arrows pointing to lymphocytic infiltrations. P values were determined by Student’s t test or by one-way ANOVA with Newman–Keuls multiple-comparison test. Error bars show mean ± SEM. *P < 0.05; **P < 0.01; ***P < 0.001.