IL6 and graft versus host disease: Our data indicate that on day 28, only the T-cell group showed geometrically elevated levels of IFN-γ, suggesting that a cytokine storm due to GVHD may have been generated, while the BCMA CAR T-cell groups showed a controlled elevated IFN-γ, with no significant cytokine storm, and the remaining cytokines (including IL-6) were at a low level below 1 ng/ml.