Chinese researchers said Wednesday they have identified two Zika antibodies from an infected patient that could provide mice with complete protection against the mosquito-borne virus, a finding that could lead to the development of much needed anti-Zika therapies and vaccines.
The study, published online in the US journal Science Translational Medicine, was conducted by the research groups of Professors Jinghua Yan and George Fu Gao from the Chinese Academy of Sciences's Institute of Microbiology.
Unlike other human antibodies under investigation that recognized both Zika and the closely related dengue virus, the antibodies used in this study exclusively targeted Zika, demonstrating a high specificity that could be important in avoiding potential side effects, such as enhanced dengue infection in regions where both viruses are endemic.
The researchers isolated immune B cells from the blood of a Zika-infected patient returning from Venezuela to China who later recovered and generated a total of 13 of antibodies that were confirmed to bind the virus.
Two of these antibodies, known as Z23 and Z3L1, potently eliminated Zika virus in vitro, without cross-reacting with dengue virus strains, and shielded mice completely from Zika virus infection.
Structural analysis suggested that the two antibodies block infection by targeting sites on the virus' envelope protein, which is known to facilitate virus entry into cells.
"Our results highlight the promise of antibody-based therapeutics and provide a structure-based rationale for the design of future Zika-specific antivirals and vaccines," Yan told Xinhua.
"Meanwhile, we have developed a platform that can isolate strongly neutralizing, specific monoclonal antibodies against any pathogen from the sera of convalescent patients in a short time, providing a powerful tool to control and limit the number of infections from future outbreaks," she said.
Zika has caused global concern due to accumulating evidence suggesting that infection is associated with a birth defect known as microcephaly in newborns and neurological complications, such as Guillain-Barre syndrome, in adults. Currently, there are no treatments or vaccines for the virus. (Xinhua)
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