Figure 2: Characterization of the colitis in Socs1^−/−Rag2^−/− mice.

(a) Histological scores of the colitis of 16-week-old Socs1^−/−Rag2^−/− mice treated with or without antibiotics for 2 weeks from 14 weeks of age (n=3). The horizontal lines indicate the mean values. (b) Histological scores of the colitis of Socs1^−/−Rag2^−/− mice (black circles, n=7), Ifng^−/−Socs1^−/−Rag2^−/− mice (black triangles, n=14), Ifng^−/−Rag2^−/− mice (white circles, n=5), Il23a^−/−Socs1^−/−Rag2^−/− mice (black diamonds, n=5), Il23a^−/−Rag2^−/− mice (white diamonds, n=3) and Ifng^−/−Socs1^−/− mice (white triangles, n=5) at 9 weeks of age. The horizontal lines indicate the mean values. (c) Macroscopic and microscopic observations of the colons of Socs1^−/−Rag2^−/− mice with or without Treg transfer. CD4⁺CD25^high T cells (2×10⁵ cells) sorted from WT mice were transferred at 10 weeks of age. The mice were killed 6 weeks after the transfer. Representative data are shown. Scale bar, 200 μm. (d) Representative histopathology of the colons of Socs1^−/−Rag2^−/− mice transferred with Tregs sorted from WT (Il10^+/+) and Il10^−/− mice. Scale bar, 100 μm (upper panel). The reconstitution of Tregs confirmed by flow cytometry (lower panel). Spleens were removed from Socs1^−/−Rag2^−/− mice without Treg transfer (lower left) or 6 weeks after the transfer with the indicated Tregs (lower middle and right), and the frequencies of CD4⁺ and Foxp3⁺ cells among TER119⁻CD11c⁻ cells gated on particular forward and side scatter were analysed. At 6 weeks after the transfer, nearly 40% of the CD4⁺ cells expressed Foxp3, and the frequency was similar between the Il10^+/+ and Il10^−/− Treg-transferred group. (e) Histological scores of the colitis of 16-week-old Socs1^−/−Rag2^−/− mice without transfer (black circles, n=3), transferred with Il10^+/+ Tregs (black diamonds, n=3) and transferred with Il10^−/− Tregs (black triangles, n=2) is shown. The horizontal lines indicate the mean values.