A team led by researchers from the University of California, Irvine, has engineered mosquitoes to produce antimalaria antibodies. In a new study appearing in Proceedings of the National Academy of Sciences, the authors describe a Cas9/guide-RNA-based gene drive system coupled to genes that code for antibodies targeting P. falciparum, the parasite that causes malaria in humans. When the gene drive system was introduced into two mosquito strains — Anopheles gambiae and Anopheles coluzzii — that can transmit the disease, the researchers saw P. falciparum antibodies in the insects' midguts and circulatory systems. They further introduced P. falciparum gametocytes into the transgenic mosquitoes and found that the transgenic insects carried fewer oocysts and sporozoites, as compared to normal mosquitoes. Subsequent modeling experiments also showed that the gene drive could reduce human infection by 50 percent to 90 percent within one to four months, in certain cases, and the results could last for three years. "These or similar strains are viable candidates for future field trials in a malaria- endemic region," the researchers write. The findings support further development of the antibody-producing gene drive as a malaria control strategy, they add.