Fig 4. GzmA ^-/- Tregs are required for prevention of gastrointestinal GvHD.

Lethally irradiated BALB/c mice (n = 9) received T cell depleted (TCD) bone marrow cells (BM) together with CD4⁺CD25^- T effector cells (squares, n = 3) and CD4⁺CD25⁺ WT Treg cells (circle, n = 3) or CD4⁺CD25⁺ gzmA ^-/- Treg cells (triangle, n = 3) from WT mice. (A) Body weight of the recipients was monitored daily. (B) Histopathological investigations of liver, small and large intestine of mice sacrified after 3 weeks. (C) Histopathological GvHD scoring 3 weeks after transplantation were graded for severity of inflammation and degree of organ destruction resulting in an organ-specific cumulative pathology score. For statistical analysis student`s t-test was performed and p values <0.05 (*) were considered significant, while p<0.01 (**) and p<0.001 (**) were considered highly significant.