Institute: University of Oxford
Characterising human monoclonal antibodies induced by vaccines against Plasmodium vivax Duffy binding protein
Progress in reducing cases of malaria worldwide has recently stalled. An effective vaccine would aid malaria elimination efforts. However, there are no licensed vaccines against the Plasmodium vivax parasite, the most common cause of malaria outside of Africa. The leading vaccine candidates against the disease-causing blood-stage infection of P. vivax are based on the parasite’s Duffy binding protein (PvDBP), a protein required by the parasite to infect red blood cells and cause malaria. We recently tested the efficacy of two candidate vaccines in clinical trials in which the vaccinated volunteers were subsequently experimentally infected with malaria.
The trials showed that one of the vaccines was partially effective and delayed the onset of malaria by slowing the growth of parasites in the blood by 50% - a major milestone for the field. This effect was mediated by vaccine-induced antibodies, proteins produced by immune cells that recognise and neutralise foreign organisms.
The aim of this project is to study the antibody response to the PvDBP vaccine in more detail by isolating single antibodies from blood samples from vaccine trial participants. These antibodies will then be tested for their ability to bind PvDBP and their ability to prevent the growth of malaria parasites in laboratory experiments. This study will help us understand which antibodies targeting PvDBP are able to prevent parasite growth and which ones are most effective at doing this. We will then use this information to improve the design of future vaccines to make a more effective vaccine against P. vivax malaria.
More about Dr Bardelli here.