Figure 1. An early pulse of Notch signaling is critical to drive pathogenic T cell alloreactivity after BMT.

(A) Dosing schedule of systemic neutralizing antibodies against DLL1 and DLL4 Notch ligands. (B) Survival, GVHD score, and weight of lethally irradiated (8.5 Gy) BALB/c mice transplanted with 5 × 10⁶ T cell–depleted (TCD) B6 BM or 5 × 10⁶ TCD B6 BM plus 5 × 10⁶ allogeneic B6 splenocytes. Isotype control versus anti-DLL1/4 antibodies were injected i.p., as shown in A (n = 10 mice/group). (C) Intracellular cytokine production by donor CD4⁺ T cells after anti-CD3/CD28 restimulation on day 6 after transplantation (n = 5 mice/group). (D) Intracellular FoxP3 in donor CD4⁺ T cells on day 6 (n = 5 mice/group). *P < 0.05, **P < 0.01, ***P < 0.001, and NS = P > 0.05, by unpaired, 2-tailed Student’s t test with Sidak’s correction for multiple comparisons. Data are representative of at least 4 experiments; error bars indicate SD.