Penetration of maturating red blood cells by Toxoplasma gondii.

Penetration of Toxoplasma gondii tachyzoites was studied in vitro using murine erythroid cells at different stages of development. Toxoplasma gondii penetrated nucleated erythroblasts and macroreticulocytes from foetal mouse liver and the circulating erythrocytes of foetal, neonatal or severely anaemic adult mice. Immature reticulocytes were more susceptible to penetration than mature ones, indicating that some change in their membrane properties occurred during maturation. The present results confirmed our previous finding that the major erythrocyte membrane-specific proteins do not prevent erythrocyte penetration since these proteins are known to be present in the reticulocyte membrane.