Plasmodium berghei: Relationship between mitosis and erythropoiesis in spleen cells of infected rats

Rats rendered polycythemic by hypoxia show a suppression of erythropoiesis and a "rebound" granulo- and lymphopoiesis in the posthypoxic period. These rats, when infected with Plasmodium berghei had a survival rate of 80%, as compared to 8% in normally infected controls. ⁵⁹Fe and [³H]thymidine uptake of spleen cells was measured from the initiation until peak parasitemia. As the infection progressed, the ratio of ³H to ⁵⁹Fe uptake declined from 37.00 to 1.40, showing a shift towards erythropoiesis. Rebound animals showed a marked decrease in Fe uptake when infected, especially during the early stages of infection. It appears that changes in the balance between the formation of erythropoiesis-oriented cells and of immune-oriented cells in the rat spleen may prove critical to the fate of the malaria-infected animal.