GM rice delivers antibodies against deadly rotavirus
A strain of rice genetically engineered to protect against diarrhoeal disease could offer a cost-effective way to protect children in developing countries, according a study published in the Journal of Clinical Investigation yesterday (8 August).
Researchers engineered the rice, called MucoRice-ARP1, by adding an antibody to fight rotavirus originally found in llamas in the rice genome.
Rotavirus is the leading cause of severe diarrhea in young children and infants, killing more than 520,000 people each year, according to the WHO. More than 85 per cent of those deaths occur in impoverished countries in Africa and Asia.
The team fed MucoRice-ARP1 to mice they subsequently infected with rotavirus, and found these mice had significantly less virus than mice fed normal rice.
The rice could be used to complement vaccinations to protect children when they are at their most vulnerable to rotavirus, say the researchers.
But it had not yet been tested on humans, and could take a decade before a final product is ready for distribution, says one of the study's authors Yoshikazu Yuki, of the University of Tokyo in Japan.
The WHO has recommended since 2009 that rotavirus vaccines be included in national immunisation programmes.
But studies have since shown that these vaccines are less effective in developing countries than in industrialised countries, protecting only 50—60 per cent of people immunised in developing countries, compared with 85—98 per cent in industrialised countries.
The reasons for the drop in effectiveness are not yet established, but weakened immune systems are a likely factor says Miren Iturriza-Gomara, a virologist at the UK-based University of Liverpool and one of the study's authors.
MucoRice-ARP1 could complement existing vaccine schedules. It would not be a substitute for a vaccine, she says, "but it's something that in certain situations could be very helpful".
For example, the rice could be given to children under two years old when rotavirus infection is most likely to prove fatal.
The research team found that MucoRice-ARP1 is most effective when consumed as a powder diluted with water, although the antibodies could also be ingested either in cooked rice or by drinking the water in which MucoRice-ARP1 is boiled.
Iturriza-Gomara says the rice could also prove useful during rotavirus outbreaks by lowering transmission rates.
Read more at SciDevNet.
Rice Farm image via Shutterstock.