THY1 and graft versus host disease: This lethal exacerbation of GVHD was not due to the depletion of Thy1+ HSCs by the anti-Thy1.2+ antibody, because the number of CD48− CD150+ lineage− c-Kit+ Sca1+ long-term HSCs was equivalent between the cGVHD and THSC-depleted groups (Figure 5G).