Résumé
Infection with Plasmodium can elicit antibodies that inhibit parasite
survival in the mosquito, when they are ingested in an infectious blood
meal. Here, we determine the transmission-reducing activity (TRA) of
naturally acquired antibodies from 648 malaria-exposed individuals using
lab-based mosquito-feeding assays. Transmission inhibition is
significantly associated with antibody responses to Pfs48/45, Pfs230, and
to 43 novel gametocyte proteins assessed by protein microarray. In
field-based mosquito-feeding assays the likelihood and rate of mosquito
infection are significantly lower for individuals reactive to Pfs48/45,
Pfs230 or to combinations of the novel TRA-associated proteins. We also
show that naturally acquired purified antibodies against key
transmission-blocking epitopes of Pfs48/45 and Pfs230 are mechanistically
involved in TRA, whereas sera depleted of these antibodies retain
high-level, complement-independent TRA. Our analysis demonstrates that
host antibody responses to gametocyte proteins are associated with reduced
malaria transmission efficiency from humans to mosquitoes.