[Target antigens for graft-versus-host disease (GVHD) and graft-versus-leukemia/tumor (GVL/T)]

The regulation of graft-versus-host disease (GVHD) and graft-versus-leukemia/tumor (GVL/T) effect is the most important issue in allogeneic stem cell transplantation. Although it is very difficult to separate GVHD and GVL/T, however, we should try to find the way to suppress GVHD and induce GVL/T at the same time. From that point of view, the induction of CTL against minor histocompatibility antigens such as HA-1 and tumor specific antigens such as BCR-ABL chimeric protein may be useful. Also, the new concept of alloreactive NK cells which have inhibitory NK cell receptor seem to be interesting to regulate GVHD and GVL/T. Further study is needed to establish new allogeneic cell therapy to obtain the clinical improvement.