Chinese scientists have discovered a candidate antibody drug for Rift Valley fever

2016, the first case of Rift Valley fever virus infection occurred in China. A Chinese man was working in Angola, Africa, when he developed symptoms such as fever and muscle joint pain. After flying back to Beijing for emergency treatment, the patient recovered and was discharged from the hospital.
, Chinese scientists have isolated monoclonal antibodies that could cure the disease in his blood.
proves that antibodies can play an important role in rift valley thermal prevention and control, and also provides an important theoretical basis for vaccine design. Gao Fu, director of the China Center for Disease Control and Prevention and a member of the Chinese Academy of Sciences, one of the authors of the paper' newsletter, said. The results were published online April 2 in Nature-Microbiology.Rift valley Chinese virus (RVFV) is not as "notorious" as viruses such as Ebola, Zika and bird flu, but Chinese epidemic prevention workers have long followed it closely.
The National Institutes of Health has listed rift valley fever virus as one of the most dangerous pathogenic microorganisms and needs urgent attention. Wang Qihui, the first author of the paper and an associate researcher at the Institute of Microbiology of the Chinese Academy of Sciences, told china Science Daily.
In 1912, an outbreak of fever, acute hepatitis, which was the main symptom of the disease in sheep in The Great Rift Valley in East Africa, resulted in the death of 90 per cent of lambs, a powerful infectious disease known as Rift Valley fever. Historically, Rift Valley fever has caused many severe damage to the livestock industry. Humans, on the other part of the world, can also develop the disease from contact with infected animals or from being bitten by diseased mosquitoes.
the majority of human patients are mild compared to animals, but for a small number of seriously ill patients, Rift Valley fever is quite dangerous. Between 2000 and June 2018, the World Health Organization was notified of 4,830 cases of severe Rift Valley fever infection worldwide, of which 967 died, with a fatality rate of nearly 20 per cent.
rift valley fever epidemic is concentrated in Africa, but in 2000 the Rift Valley fever virus broke through geographical restrictions and made landfall in the Arabian Peninsula, causing widespread outbreaks in Saudi Arabia and Yemen. The Chinese patient mentioned at the beginning of the article contracted the disease in Angola. Intriguingly, however, Angola has long been considered to be not an endemic region for Rift Valley fever.
in the lab, researchers have found that more than 20 mosquitoes can transmit the Rift Valley fever virus, and that these mosquito distributions add up to all land areas around the world except Greenland in the Arctic. What's more, the Rift Valley fever virus is so stable that the eggs of mosquitoes that carry it can hatch poisonous mosquito larvae years later.
" means that there are also potential risks in areas where large-scale outbreaks have not yet occurred, and it is clear that not enough attention has been paid to these areas. Wang Qihui said.Gn and Gc on the surface of the Rift Valley Fever virus, which are the key proteins responsible for the virus's fusion with cell adhesion and membrane.
in the blood of Chinese patients recovering, the researchers used Gn and Gc as "baits" to isolate eight antibodies that bind to Gn and one to Gc. Subsequent experiments have shown that antibodies binding to Gn have very high meso-activity. In contrast, the isolated Gc antibodies showed weaker merging activity.
researchers created a group of mouse models infected with the Rift Valley fever virus, which usually dies. But the eight mice injected with Gn antibodies not only survived, but also maintained normal weight gain. Early injection of Gn antibodies in healthy mice can also be effective in preventing Rift Valley fever virus infection.
, Gc antibodies showed no significant therapeutic and preventive effects.
researchers further found that Gn antibodies can menies the infection by binding to the Gn cystic membrane protein on viral particles, blocking the virus's adhesion to the cells. This may be how Gn antibodies protect the body.the Rift Valley fever virus has lacked commercial human vaccines and specific therapeutic drugs since it was officially identified in 1931.
, it is of great practical significance to look for human drugs to prevent and treat Rift Valley fever virus infection. "The experience of saving Ebola patients tells us that antibody therapy is a lifesaface for people infected with the virus." Yan Jinghua, one of the authors of the paper and a researcher at the Institute of Microbiology of the Chinese Academy of Sciences, told the China Science Daily.
the findings are exciting, but review experts say Gn antibodies, as a candidate drug, are not enough to deal with mutations in viral genes.
researchers studied more than 100 complete viral genome sequences and found that a total of five viruses had mutations in the Gn sequence, and that the binding forces of these mutated Gn proteins, and Gn-specific antibodies, had declined to varying degrees.
To this, Yan Jinghua said, one antibody treatment alone is indeed prone to immune escape problems, so they will continue to screen more target binding antibodies, hoping to use a variety of antibodies to bring out a life-saving "cocktail."
" May seem a long way from China, but infectious diseases have no borders. With the increasing frequency of international exchanges, Chinese researchers have a responsibility to plan ahead and move the epidemic prevention and control pass forward. Yan Jinghua said. (Source: Li Chenyang, China Science Journal)
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