KMT2A and leukemia: In this low MLL-AF9 leukemia burden, anti-murine ST2 treatment with IgG-281 causes no death for a follow-up of 180 days compared to the IgG1-treated control group with all the death happening before day 60 post-challenge (Fig. 9N) and leukemic cells are undetectable on day 35 in the IgG-281 treated mice, suggesting elimination of all leukemia and full rescue of the mice (Fig. 9N).