Two linear epitopes on the SARS-CoV-2 spike protein that elicit neutralizing antibodies in COVID-19 patients

Given the ongoing SARS-CoV-2 pandemic, identification of immunogenic targets against the coronavirus spike glycoprotein will provide crucial advances towards the development of sensitive diagnostic tools and potential vaccines. In this study, using pools of overlapping linear B-cell peptides, we report two IgG immunodominant regions on SARS-CoV-2 spike glycoprotein that are recognised by sera from COVID-19 convalescent patients. Notably, one is specific to SARS-CoV-2, which is located in close proximity to the receptor binding domain. The other region, which is localised at the fusion peptide, could potentially function as a pan-SARS target. Functionally, antibody depletion assays demonstrate that antibodies targeting these immunodominant regions significantly also elevate neutralisation capacities. Taken together, identification and validation of the neutralising B-cell epitopes will provide insights towards the design of therapeutics and vaccine candidates against this priority coronavirus.

Chek Meng Poh, Guillaume Carissimo, Bei Wang, Siti Naqiah Amrun, Cheryl Yi-Pin Lee, Rhonda Sin-Ling Chee, Siew-Wai Fong, Nicholas Kim-Wah Yeo, Wen-Hsin Lee, Anthony Torres-Ruesta, Yee-Sin Leo, Mark I-Cheng Chen, Seow-Yen Tan, Louis Yi Ann Chai, Shirin Kalimuddin, Shirley Seek Geh Kheng, Siew-Yee Thien, Barnaby Edward Young, David C. Lye, Brendon John Hanson, Cheng-I Wang, Laurent Renia, Lisa F. P. Ng