Paris: Researchers said today they had discovered a unique microscopic channel through which malaria parasites must pass to infect red blood cells, a finding that
opens up a highly promising target for a vaccine.
The doorway mechanism is common to all known strains of the deadliest mosquito-borne pathogen, Plasmodium falciparum, which means that a future vaccine could in theory work against all of them, according to the study published in the journal `Nature`.
The death toll from malaria has declined by a fifth over the last decade, but the disease still claims some 800,000 lives every year, mostly children under five in sub-Saharan Africa.
"Our findings were unexpected and have completely changed the way in which we view the invasion process," said Gavin Wright of the Wellcome Trust Sanger Institute and the study`s senior co-author.
The breakthrough "seems to have revealed an Achilles` heel in the way the parasite invades our red blood cells."
Up to now, scientists assumed that P falciparum had several options for piercing the defences of blood cells.
But in experiments, Wright and colleagues showed that intrusion depends on the interaction between a specific molecule on the parasite, called a ligand, and a specific
receptor on the blood cell.
Blocking this interaction repels the pathogen`s attempt to breach the cell`s protective wall, they found.