Vaccine blocks malaria transmission in lab experiments

Jul 22, 2009

Researchers at the Johns Hopkins Malaria Research Institute have for the first time produced a malarial protein (Pfs48/45) in the proper conformation and quantity to generate a significant immune response in mice and non-human primates for use in a potential transmission-blocking vaccine.

Antibodies induced by Pfs48/45 protein vaccine effectively blocked the sexual development of the malaria-causing parasite, Plasmodium, as it grows within the mosquito. Sexual development is a critical step in the parasite's life cycle and necessary for continued transmission of malaria from mosquitoes to humans. The study is published in the July 22 edition of the journal PLoS ONE.

"Development of a successful transmission-blocking vaccine is an essential step in efforts to control the global spread of malaria. In our study, we demonstrate the relative ease of expression and induction of potent transmission-blocking antibodies in mice and non-human primates. This approach provides a compelling rationale and basis for testing a transmission-blocking vaccine in humans," said Nirbhay Kumar, PhD, senior author of the study and professor in Johns Hopkins Bloomberg School of Public Health's W. Harry Feinstone Department of and Immunology.

For the study, the research team expressed full-length Pfs48/45 in E. coli bacteria to produce the vaccine. Previous attempts to fully express the protein had not been successful. The vaccine was first given to mice in the laboratory. The vaccine was also tested in non-human primates (Olive baboons) in Kenya with similar results. According to the study, a single-dose provided a 93 percent transmission-blocking immune response, reaching greater than 98 percent after a booster given several months later.

"This is an exciting beginning to what might become an important tool in the arsenal for malaria control and progressive elimination of ," said Kumar. There is no animal reservoir for human malaria and in that regard it is possible to gradually reduce malaria transmission to a point of almost eradication. However, Kumar cautioned that more research is needed to achieve that goal. For one, similar research efforts are needed to reduce transmission of Plasmodium vivax, another major human malaria parasite.

affects greater than 500 million people worldwide and is estimated to kill over one million people each year, most of whom are children living in Africa.

Source: Johns Hopkins University (news : web)

Explore further: Growing a blood vessel in a week

add to favorites email to friend print save as pdf

Related Stories

Sugar identified as key to malaria parasite invasion

Sep 10, 2007

Researchers at the Johns Hopkins Malaria Research Institute (JHMRI) have identified a sugar in mosquitoes that allows the malaria-causing parasite, Plasmodium falciparum, to attach itself to the mosquito’s gut. Invasion ...

Vaccine hope for malaria

May 23, 2007

One person dies of it every 30 seconds, it rivals HIV and tuberculosis as the world’s most deadly infection and the vast majority of its victims are under five years old. Now, just over 100 years since Britain’s Sir Ronald ...

Recommended for you

Growing a blood vessel in a week

7 hours ago

The technology for creating new tissues from stem cells has taken a giant leap forward. Three tablespoons of blood are all that is needed to grow a brand new blood vessel in just seven days. This is shown ...

Testing time for stem cells

10 hours ago

DefiniGEN is one of the first commercial opportunities to arise from Cambridge's expertise in stem cell research. Here, we look at some of the fundamental research that enables it to supply liver and pancreatic ...

Team finds key signaling pathway in cause of preeclampsia

Oct 23, 2014

A team of researchers led by a Wayne State University School of Medicine associate professor of obstetrics and gynecology has published findings that provide novel insight into the cause of preeclampsia, the leading cause ...

Rapid test to diagnose severe sepsis

Oct 23, 2014

A new test, developed by University of British Columbia researchers, could help physicians predict within an hour if a patient will develop severe sepsis so they can begin treatment immediately.

User comments : 0