On April 24, the reporter learned from Chengdu ABlink Biotech Co.,Ltd. ("ABlink" for short), a company in the Tianfu Life Science Park in Chengdu High-tech Zone, that a few days ago, ABlink located in the Tianfu Life Science Park used its 100-billion-level synthetic human antibody library to successfully screen out neutralizing antibodies against the new coronavirus (SARS-COV-2), which can be used to develop antibody drugs for the treatment of the new coronavirus. Related achievements have been released on the largest preprint platform BioRxiv in the biological field and wait for the peer review of foreign academic journals.

ABlink develops a new coronavirus testing kit with its self-developed antibody.

ABlink was founded by Dr. Liu Jianghai in 2016. In 2017, it had successfully developed a new generation of "Phage Display Antibody Library" with independent intellectual property rights. Currently, it has established a batch of "fully human antibody libraries and synthetic antibodies" with independent intellectual property rights.  It has been verified that the antibody libraries contain species of 10 to the 13 power (100-billion-level).

After the outbreak of COVID-19, ABlink used the antibody library technology platform to screen out the detection antibodies against the new coronavirus. On the one hand, it provided antibody detection materials for downstream partners to develop detection kits and rapid detection methods. On the other hand, kits are developed on a smaller scale to serve vaccine companies.

"It is easy to detect new coronavirus with antibodies, but it is much more complicated to screen out therapeutic antibodies and develop drugs."  Dr. Zeng Xin, the technical director of ABlink, introduced that as the epidemic changed at home and abroad, the company decided to adjust its strategy in screening and testing antibodies, and began to screen out antibodies with therapeutic potential for the new coronavirus in order to provide "seeds" for subsequent therapeutic drug development.

Dr. Zeng Xin was showing us Ablink's antibody library

Speaking in a more vivid way, the antibody library is like a reservoir with many fish (antibodies). When the specific protein (disease treatment target) on the surface of the antigen acts as a bait for fishing, it is easy for us to get antibodies with good affinity and high specificity.  Compared with traditional hybridoma technology, phage display antibody library also has other strengths, such as fast screening cycle, free of animals testings and direct access to human/humanized antibodies.

“Testing antibodies or antibodies isolated from patients are generally not sufficiently targeted and have little medicinal potential,” introduced by Dr. Zeng Xin. In order to screen out therapeutic antibodies with medicinal potential from the antibody library, Zeng Xin, a Ph.D. in structural biology at Tsinghua University, designed and analyzed protein structures of new coronavirus, SARS, and known SARS antibodies in detail. A unique "fishing strategy" is designed, that is, using the structural features of the specific binding of the S protein on the surface of the new coronavirus to human receptors as bait. Antibodies in the antibody library that can block the binding of the virus to the receptor are selected out, thereby preventing the virus from entering the human body Cell and achieving the purpose of "defending the enemy from the outside".

Dr. Zeng Xin was showing us Ablink's antibody library

"After screening antibodies through a competitive strategy, we have verified by ELISA and fake virus that it is of value for medicinal development and can be used for drug treatment of new coronavirus in the future. We also hope that potential social resources can participate in cooperation and accelerate progress".

Previously, many well-known scientific research teams at home and abroad announced the discovery of neutralizing monoclonal antibodies from recovered patients.  At present, there are no reported cases of screening out therapeutic antibodies for new coronavirus from the synthetic human antibody libraries in China. The discovery of ABlink has made up for the gap in the field of screening antibodies by using human antibody libraries in China.

Dr. Zeng Xin is showing us ABlink's antibody library