Figure 2. Heart allografts transplanted into Nox2^fl/flFoxP3Cre⁺ mice have higher Treg infiltration and better outcomes.

Nox2^fl/flFoxP3Cre⁺ mice and littermate controls (Nox2^fl/fl) were transplanted with hearts from CB6F1 mice. Mice transplanted with hearts from C57BL/6 mice were used as isograft controls. (A) Allograft survival curves. Some mice were treated daily with cyclosporin (30 mg/kg) s.c. for 10 days after transplantation (n = 4–5 per group). (B) Plasma troponin-I levels 7 days after transplant. (C and D) Plasma alloantibodies 7 and 100 days after the transplant. Representative histograms in D show the data obtained 100 days after transplant. (n = 3–5 per group). (E) Plots represent data from 3 allografts per time evaluated. The nontransplanted group represents data from 3 native hearts of naive nontransplanted mice. (F and G) Representative plots of CD25⁺FoxP3⁺ cells within the CD4⁺ cell population (F) and cells/mg of heart allograft 7 days after transplant (G). (H) Treg/Teff ratios. (I and J) Presence of CD4⁺ and CD8⁺ cells in transplanted hearts. Representative plots are shown in I, and cells/mg tissue is shown in J. (K) IFN-γ levels in heart allograft homogenates 7 days after surgery. Data are shown as mean ± SEM. †P < 0.05, *P < 0.05 compared with Nox2^fl/fl mice, Mantel-Cox test (A); *P < 0.05 for indicated comparisons in B and C, G and H, and J and K, using Kruskal-Wallis followed by Dunn’s post test (n = 3–5 per group).