A genetically engineered mosquito that vaccinates as it bites has been developed by Japanese scientists, reports The Telegraph, London.
Scientists have developed the genetically modified mosquito which they claim can work as a natural “flying vaccinator” to spread vaccine against malaria instead of the disease.
A research, led by Jichi Medical University in Japan, has revealed that mosquito genetic engineering may turn the blood-sucking “transmitter” into a “flying vaccinator” thereby providing a new strategy for biological control over malaria.
The research targets the saliva gland of the Anopheles stephensi mosquitoes, the main vectors of human malaria.
Blood-sucking arthropods including mosquitoes, sand flies and ticks transmit numerous infectious agents during blood feeding. This includes the deadly malaria disease, which kills between one to two million people, mostly African children, a year.
“The lack of an effective vaccine means control of the carrier has become a crucial objective to combating the disease,” lead scientist Shigeto Yoshida said.
For the past decade, it has been theorized that genetic engineering of the mosquito could create a “flying vaccinator”, raising hopes for their use as a new strategy for malaria control. However so far research has been limited to a study of the insect's gut.
“Following bites, protective immune responses are induced, just like a conventional vaccination but with no pain and no cost”, Yoshida said. “What's more, continuous exposure to bites will maintain high levels of protective immunity, through natural boosting, for a lifetime. So the insect shifts from being a pest to being beneficial,” he added.
In the latest study, Yoshida's team successfully generated a transgenic mosquito which had the Leishmania vaccine in its saliva. Bites from the insect succeeded in raising antibodies, indicating successful immunization with the Leishmania vaccine through blood feeding.
“For the past decade it has been postulated that the salivary gland could be the way to gain biological control over this important infectious disease. In this study we have shown for the first time the achievement of the original concept of the ‘flying vaccinator',” Yoshida said. The findings have been published in the ‘Biology & Nature' journal.
However, Yoshida admitted that regulatory and ethical problems would prevent the prototype from flying. There is a huge variation in the number of mosquito bites one person receives compared to the next, so people exposed to the prototype would get very different vaccine doses, the ‘Biology & Nature' journal reported.