New mosquito-targeting insecticide offers hope of 'malaria-free' future

Researchers have come up with a new antibody insecticide that targets malaria mosquitoes.

Recent progress in halting the spread of the disease has hinged on the use of insecticide-treated bed nets and spraying programmes that target the insect that spreads the disease, the African malaria mosquito (Anopheles gambiae).

However, the insects are fighting back, developing resistance to insecticides such as pyrethroid that control their numbers, forcing Brian Foy and Jacob Meyers from Colorado State University to think of alternative control strategies.

The duo decided to test whether antibodies targeted at a key component of the malaria mosquito's nervous system could be fed to the insects in a blood meal to kill them.

Identifying a glutamate gated chloride channel (the mosquito glutamate gated chloride channel - AgGluCl), which is an essential component of the insect's nervous system, to be the target of their novel strategy the duo decided to generate antibodies that specifically targeted a portion of the protein that is exposed on the surface of nerves to try to exterminate the disease carriers.

However, Meyers admits that the strategy was risky as antibodies against a single mosquito antigen have never been shown to have mosquitocidal properties before and the majority of previous research had focused on midgut antigens, while they were targeting a neuronal antigen expressed only in tissues found outside of the midgut.

Having shown that antibodies targeted to the glutamate gated chloride channel in blood meals can be effective insecticides, Meyers and Foy are keen to find out if antibody-laced blood meals are equally deadly in real life.

Meyers said that cattle are a major blood meal source for multiple malaria vectors, explaining that any malaria-harbouring mosquito that consumed blood carrying the toxic antibodies during the malaria parasite's incubation period would die, disrupting transmission of the disease and offering hope of a malaria-free future for generations to come.

The study appears in The Journal of Experimental Biology.