IL15 and T-cell large granular lymphocyte leukemia: Previous work by Zhang et al. [28] and Saadatpour et al. [46] has shown that in the sustained presence of the external signals IL15, PDGF, and Stimuli (antigen presentation) the system has two attractors: one that recapitulates the survival phenotype and node deregulations seen in T-LGL leukemia, and a second one that corresponds to self-programmed cell death (apoptosis) (see S4 Text for more details about attractor specification).