Experimental severe malaria is resolved by targeting newly-identified monocyte subsets using immune-modifying particles combined with artesunate

Current treatment of severe malaria and associated cerebral malaria (CM) and respiratory distress syndromes are directed primarily at the parasite. Targeting the parasite has only partial efficacy in advanced infection, as neurological damage and respiratory distress are due to accumulation of host blood cells in the brain microvasculature and lung interstitium. Here, computational analysis identifies Ly6Clo monocytes as a major component of the immune infiltrate in both organs in a preclinical mouse model. Specifically targeting Ly6Clo monocyte precursors, identified by adoptive transfer, with immune-modifying particles (IMP) prevents experimental CM (ECM) in 50% of Plasmodium berghei ANKA-infected mice in early treatment protocols. Furthermore, treatment at onset of clinical ECM with 2 doses of a novel combination of IMP and anti-malarial drug artesunate results in 88% survival. This combination confers protection against ECM and mortality in late stage severe experimental malaria and provides a viable advance on current treatment regimens.
Niewold, Cohen et al. identify Ly6Clo monocytes as a major component of immune cell sequestration in a mouse model of severe malaria. They show that combined immune-modifying particles and anti-malarial drug treatment at the onset of disease signs results in 88% survival of malaria-infected mice.