Immune and pathophysiological processes in baboons experimentally infected with Ebola virus adapted to guinea pigs.

The dynamics of pathophysiological and immunological parameters monitored in monkeys Papio hamadryas infected with the guinea pig-adapted Ebola virus strain demonstrated that this viral strain preserved its virulence for monkeys and caused the disease with characteristic features similar to those caused by non-adapted Ebola virus. However, certain previously unknown patterns have been observed: (1) prolongation of the febrile period by two days; (2) extended period was characterized by stability of serum biochemical parameters; (3) marked vacuolization of the neutrophil cytoplasm; (4) appearance of juvenile lymphocytes on day 3 and by the end of the disease; and (5) a considerable increase in the spontaneous mononuclear proliferation (along with a decrease in the mitogen-induced proliferation) during the terminal stage of infection. The severity of pathological coagulation was found to correlate with the activity of serum cytokines IFN-alpha and TNF-alpha: their activities increased about 250- and 100-fold, respectively. There was significant alteration in the activity of natural killer cells, that dropped by the time of animal death.