dmPGE₂ pulsed grafts maintain repopulating ability through serial transplantations. (A) Increased chimerism of dmPGE₂-treated cells vs vehicle is shown for primary transplant at 20 weeks (time of secondary transplant) and in a subcohort at 32 weeks (time of 12-week analysis of secondary transplant); for secondary transplant at 12 weeks and 24 weeks; and for tertiary, quaternary, and quinary at 12 weeks. Data for 20-week primary transplant were from 2 pooled experiments, n = 5 mice per group, per experiment, each assayed individually. Data for secondary, tertiary, quaternary, and quinary transplants were from n = 5 mice per group, each assayed individually. Data are expressed as mean ± SEM; *P < .05. (B) Relative contribution to lineages of myeloid and B- and T-lymphoid. Multilineage analysis for primary transplant (32 weeks) and at 12 weeks posttransplant in serially transplanted secondary, tertiary, and quaternary mice. n = 5-10 mice per group, each assayed individually. (C) Representative Wright’s Giemsa-stained cytospins from normal bone marrow, marrow from secondary bone marrow transplant 12 weeks after transplantation, and marrow from quinary transplanted mice 12 weeks after transplantation. Cytospins were photographed at ×200 (×20 objective) with a Leica DM2500 Microscope outfitted with Q-Imaging micropublisher camera (W. Nushbaum Inc., McHenry, IL). Bone marrow cytospins show normal cellularity. Both myeloid and precursors are present and show normal maturation as well as megakaryocytes. There was no evidence of myeloid hyperplasia, no noticeable increase in myeloid or erythroid blasts, and no obvious increase in immature granulocytic, monocytic cells, or evidence of lymphoblastic transformation.