Carbohydrates pave way to improve malaria vaccines

Carbohydrates pave way to improve malaria vaccines

Illuminate newsletter, December 2017
December 2017

Associate Professor Justin Boddey and Dr Ethan Goddard-Borger
Associate Professor Justin Boddey (left) and Dr Ethan
Goddard-Borger in the Institute’s world-class insectary.

Researchers have shown for the first time that carbohydrates on the surface of malaria parasites play a critical role in their ability to infect mosquito and human hosts.

The discovery suggests steps for improving the only malaria vaccine approved to protect people against the deadliest form of the disease, Plasmodium falciparum.

Carbohydrate ‘tags’ crucial

Associate Professor Justin Boddey, who co-led the research, said the malaria parasite ‘tagged’ its proteins with carbohydrates in order to stabilise and transport them. This process was crucial to completing the malaria lifecycle.

“This discovery reveals that carbohydrates are very important, in two completely different stages of the malaria lifecycle: in the earliest stages of human infection and, later, when the parasite is transmitted back to the mosquito from an infected human,” he said.

Associate Professor Boddey said interfering with the parasite’s ability to attach carbohydrates to its proteins hindered liver infection and transmission to the mosquito.

“We’ve found that disrupting the tagging weakens the parasite to the point that it cannot survive in the host,” he said.

Improving vaccine design

Dr Ethan Goddard-Borger said the team’s new research had attracted a lot of interest because of the implications for improving current malaria vaccine design. 

“The first malaria vaccine – RTS,S/AS01 – approved for human use by European regulators in 2015 has not been as successful as hoped,” Dr Goddard-Borger said.

“It may be that a version of [the malaria vaccine] with added carbohydrates will perform better.”

“With our new study, we’ve shown that the parasite protein is tagged with carbohydrates, making it slightly different to the vaccine, so the antibodies produced may not be optimal for recognising target parasites.”

He said there were many documented cases where attaching carbohydrates to a protein improved its efficacy as a vaccine.

“It may be that a version of RTS,S with added carbohydrates will perform better than the current vaccine,” he said.

About Malaria

Malaria infects more than 200 million people worldwide each year and kills around 450,000 people, predominantly pregnant women and children. 

Super Content: 
Malaria parasite in the bloodstream

Visualisation of the parasite infection inside a pregnant female mosquito.

Close up view of pipetting in lab

We have developed the first malaria vaccine that can be tailored to match many different strains of malaria.