IL1B and leukemia: A closer examination ofneutrophil-stem cell communications indicated that interactions mediated by IL-1β,TGF-β, and Oncostatin M were enhanced inPtpn11E76K/+ mice compared to those in WTmice (Extended Data Fig. 5C), providing additional evidence that leukemia-initiatingPtpn11-mutated stem cells were situated in an inflammatorymicroenvironment.