We further examined in this prospective cohort IL-6 and TNFR1 early after HCT, and although TNFR1 was associated with SOS development and correlated with HA and ST2, neither IL-6 nor TNFR1 was associated with GVHD, as has been shown in a previous prospective pediatric cohort focused on analyzing NRM and GVHD (28). This evidence concerns the gene IL6 and graft versus host disease.