Characterization of a subpopulation of mouse red blood cells as preferential target for malarial invasion.

Abstract

Cell electrophoresis was used to study a distinct subpopulation of murine red blood cells (RBC). These RBC are normally found in the spleen and bone marrow. They appear in the peripheral blood when mice are mildly bled or sucked by mosquitos. These cells have been characterized as having larger size, light density, lower electrophoretic mobility, and being more resistant to lysis with unsaturated fatty acids and in glycerol-containing medium than mature erythrocytes. All their features suggest that their differentiation status represents an intermediate stage between reticulocytes and adult RBC. In vitro Plasmodium invasion tests showed their increased sensitivity to invasion by the parasites. The extent of their spreading in the blood was found to be strain-dependent, being more pronounced in C57B1/6 mice, highly susceptible to developing cerebral malaria after infection with Plasmodium berghei, as compared to Balb/c, a nonsusceptible strain of mice.