An international team of researchers has created a mouse which accurately mimics the human immune response to malarial infection. The new model will make it easier to test potential vaccines against the deadly disease. The work, which was funded by the EU under the Marie Curie scheme for researcher mobility, and the UK's Medical Research Council, is published in the journal Public Library of Science Pathogens. Until now, researchers have lacked a reliable animal model for human malaria. When infected with the parasite that causes malaria in humans, mice do not get sick, and their immune systems respond differently to the parasite. This means that scientists who developed antibody vaccines which were effective in a test tube have had no reliable way of testing it in a living animal. In this latest study, British, Dutch and Australian scientists took a mouse parasite that is closely related to human malaria and genetically modified it to produce an antigen that the human immune system recognises. They then genetically modified mice so that their white blood cells had a human molecule on their surface which would recognise the parasite and bring about its destruction. The team tested this model using an antibody vaccine they had created from the blood of some people from Gambia who have natural immunity to malaria. Tests showed that mice given these antibodies were protected from the parasite. 'Our results are very, very significant,' said Dr Richard Pleass of the University of Nottingham's Institute of Genetics. 'We have made the best possible animal model you can get in the absence of working on humans or higher primates, as well as developing a novel therapeutic entity.' The team now hopes to refine the mouse model further and move on to clinical trials in humans. Malaria is caused by parasites transmitted by mosquitoes. It infects around 400 million people a year, and kills over one million, most of them small children living in sub-Saharan Africa. As the malaria parasite continues to become resistant to anti-malarial drugs, the hunt for a safe, effective vaccine is becoming ever more important.