Figure 2. IL-12Rβ2 on recipient non-hematopoietic cells is important for aGVHD development.

Lethally irradiated B6 Ly5.1⁺ mice (1100cGy, n=20) were transplanted with 5×10⁶ TCD-BM from WT and IL-12Rβ2KO (Ly5.2⁺) B6 mice. After 8–10 weeks, engraftment was confirmed by percentage of CD45.2⁺ cells in the peripheral blood mononuclear cells. The chimeras were lethally irradiated and transplanted with 5×10⁶ TCD-BM alone (BMA) (n=5) or plus purified T cells (n=20) from FVB donors. Recipients were monitored for survival (A) and body weight loss (B) until 80 days post second BMT. Lethally irradiated WT C57BL/6 and IL-12Rβ2KO mice were transplanted with 5×10⁶ TCD-BM from B6 Ly5.1⁺ mice. The chimeras were then lethally irradiated and transplanted with 5×10⁶ TCD-BM alone (n=4) or plus 1–1.5 × 10⁶ purified T cells (n=24) from FVB donors as successful engraftment was confirmed. Recipients were monitored for survival (C) and body weight loss (D) until 80 days post second BMT. Data shown are from 2 replicate experiments for A and B or from 4 repeated experiments for C and D. Log-rank (Mantel-Cox) test (A and C) was used for comparison of survival between groups. Nonparametric Mann-Whitney U test (B and D) was used to compare body weight loss between groups. Statistical data were presented as mean ± 1SD; significance was determined by Student’s t test. *** p < 0.001.