Histopathological examination of the GVL experiments shown in Fig 5A. (A) Administration of anti–TNF- MoAb resulted in early death with marked hepatosplenomegaly (left) compared with an age-matched normal mouse (right). The liver section obtained at the time of death showed massive leukemia infiltration (B). (C) Liver section obtained from gld BMS recipients on day 28 showed focal mononuclear infiltration around portal area, but there was no residual leukemia cells in any fields of the section. Residual leukemia cell was not detected in spleen, BM, or peripheral blood. (D) Residual leukemia cells were observed in small areas of the liver section from the PKO BMS recipients. Each figure shows a representative of three similar experiments. Similar results were also observed by using another tumor P815 cells. Original magnification × 400.