High Parasite Burdens Cause Liver Damage in Mice following Plasmodium berghei ANKA Infection Independently of CD8+T Cell-Mediated Immune Pathology

Abstract

Infection of C57BL/6 mice with Plasmodium berghei ANKA induces a fatal neurological disease commonly referred to as experimental cerebral malaria. The onset of neurological symptoms and mortality depend on pathogenic CD8(+) T cells and elevated parasite burdens in the brain. Here we provide clear evidence of liver damage in this model, which precedes and is independent of the onset of neurological symptoms. Large numbers of parasite-specific CD8(+) T cells accumulated in the liver following P. berghei ANKA infection. However, systemic depletion of these cells at various times during infection, while preventing neurological symptoms, failed to protect against liver damage or ameliorate it once established. In contrast, rapid, drug-mediated removal of parasites prevented hepatic injury if administered early and quickly resolved liver damage if administered after the onset of clinical symptoms. These data indicate that CD8(+) T cell-mediated immune pathology occurs in the brain but not the liver, while parasite-dependent pathology occurs in both organs during P. berghei ANKA infection. Therefore, we show that P. berghei ANKA infection of C57BL/6 mice is a multiorgan disease driven by the accumulation of parasites, which is also characterized by organ-specific CD8(+) T cell-mediated pathology.