Erythropoiesis in Lethally Irradiated Mice grafted with Bone Marrow or Spleen Cells

Abstract

IN a recent paper OKunewick et al.¹ reported that splenic erythropoiesis, denned as the 24 h uptake of iron-59 into the spleen, in mice lethally irradiated and grafted, depends on the source of the grafted cells. They found that grafting 10⁶ bone marrow cells gave a greater uptake of iron-59 into the recipient spleen than grafting 10⁶ spleen cells. In a second series of experiments, they found that 4 × 10⁶ bone marrow cells grafted gave higher values than 4 × 10⁷ spleen cells. They concluded that the relative erythropoietic activity of the spleen derived from spleen or bone marrow grafts is not a function of the number of cells administered and that the spleens are more erythro-poietically active if the animals have been grafted with bone marrow as opposed to spleen cells.