Immunopathology of cerebral malaria: morphological evidence of parasite sequestration in murine brain microvasculature.

A murine model that closely resembles human cerebral malaria is presented, in which characteristic features of parasite sequestration and inflammation in the brain are clearly demonstrable. "Young" (BALB/c x C57BL/6)F(1) mice infected with Plasmodium berghei (ANKA) developed typical neurological symptoms 7 to 8 days later and then died, although their parasitemias were below 20%. Older animals were less susceptible. Immunohistopathology and ultrastructure demonstrated that neurological symptoms were associated with sequestration of both parasitized erythrocytes and leukocytes and with clogging and rupture of vessels in both cerebral and cerebellar regions. Increases in tumor necrosis factor alpha and CD54 expression were also present. Similar phenomena were absent or substantially reduced in older infected but asymptomatic animals. These findings suggest that this murine model is suitable both for determining precise pathogenetic features of the cerebral form of the disease and for evaluating circumventive interventions.