NK cells inhibit Plasmodium falciparum growth in red blood cells via antibody-dependent cellular cytotoxicity

G Arora, GT Hart, J Manzella-Lapeira… - Elife, 2018 - elifesciences.org
G Arora, GT Hart, J Manzella-Lapeira, JYA Doritchamou, DL Narum, LM Thomas…
Elife, 2018elifesciences.org
Antibodies acquired naturally through repeated exposure to Plasmodium falciparum are
essential in the control of blood-stage malaria. Antibody-dependent functions may include
neutralization of parasite–host interactions, complement activation, and activation of Fc
receptor functions. A role of antibody-dependent cellular cytotoxicity (ADCC) by natural killer
(NK) cells in protection from malaria has not been established. Here we show that IgG
isolated from adults living in a malaria-endemic region activated ADCC by primary human …
Antibodies acquired naturally through repeated exposure to Plasmodium falciparum are essential in the control of blood-stage malaria. Antibody-dependent functions may include neutralization of parasite–host interactions, complement activation, and activation of Fc receptor functions. A role of antibody-dependent cellular cytotoxicity (ADCC) by natural killer (NK) cells in protection from malaria has not been established. Here we show that IgG isolated from adults living in a malaria-endemic region activated ADCC by primary human NK cells, which lysed infected red blood cells (RBCs) and inhibited parasite growth in an in vitro assay for ADCC-dependent growth inhibition. RBC lysis by NK cells was highly selective for infected RBCs in a mixed culture with uninfected RBCs. Human antibodies to P. falciparum antigens PfEMP1 and RIFIN were sufficient to promote NK-dependent growth inhibition. As these results implicate acquired immunity through NK-mediated ADCC, antibody-based vaccines that target bloodstream parasites should consider this new mechanism of action.
eLife