Figure 1. Tissue-specific recognition of mHAgs may permit separation of GVL and GVHD. Donor T cells specific for mHAgs that are broadly expressed by both hematopoietic and nonhematopoietic cells have been implicated in GVHD. Donor T cells specific for mHAgs that are expressed preferentially or selectively in recipient hematopoietic cells including leukemia progenitors may be targets for a GVL response without GVHD.
Figure 2. Evaluating T-cell recognition of leukemia progenitors using NOD/SCID mice. The leukemia cell population consists of a hierarchy of cells with distinct capacity for self-renewal. A putative stem cell is required for engraftment in irradiated NOD/SCID mice. The ability to purge the leukemia population of cells capable of establishing leukemic hematopoiesis by co-culture with antigen-specific T cells can be used to assess recognition of the leukemic stem cell.