'Method to rapidly identify antibodies against coronavirus from convalescent plasma developed'

Researchers have used a single-cell analysis method to identify multiple antibodies from COVID-19 patients that could neutralise the novel coronavirus, an advance which may lead to better therapeutics against the deadly disease.

According to the scientists, including Sunney Xie, director of the Beijing Advanced Innovation Center for Genomics at Peking University, antibodies could be successfully used to treat viruses like Ebola, AIDS, and MERS.

In the current study, published in the journal Cell, the scientists used a method called high-throughput single-cell genome sequencing to identify the antibodies from convalescent plasma, a component of patients' blood.

Citing earlier studies, the researchers said antibodies can lead to significant recovery of COVID-19 patients.

Convalescent patients' plasma, which contains neutralising antibodies produced by the immune response, has led to a clear clinical improvement of both mild and severe COVID-19 patients, they noted in the study.

However, the scientists said screening for potent neutralising molecules called monoclonal antibodies (mAbs) from the immune system's B cells is often a slow and laborious process.

They said the existing methods are particularly not ideal when responding to a global health emergency.

Since only some B cells produce antibodies specific to neutralising the virus, the researchers said, a process to rapidly screen for those cells producing the desired immune molecules was needed.

In this study, the researchers demonstrated a rapid and efficient single-cell genome sequencing method to narrow down on specific B cells, and identify SARS-CoV-2 neutralising antibodies from convalescent COVID-19 patients.

"We showed that high-throughput single-cell sequencing could lead to the identification of highly potent neutralizing mAbs that have strong therapeutic and prophylactic efficacy," the scientists noted in the study.

The method could greatly assist in the intervention of prevailing and emerging infectious diseases, such as COVID-19, they said.

Following the discovery of the antibodies, they tested them in genetically engineered mice expressing the human form of the receptor ACE2, which is the gateway protein used by the novel coronavirus to enter cells.

From this experiment, the researchers found that some of the antibodies identified by the scientists could indeed neutralise the virus.

"The potent neutralizing antibodies we identified may provide an effective therapeutic and prophylactic solution, evidenced by the results on hACE2 transgenic mice," the scientists noted.

They added that clinical trials using the antibodies are currently underway.