Scientists discover SARS-CoV-2-specific T-cell immunity in patients with recovered COVID-19 and SARS

T cells, along with antibodies, are an integral part of the human immune response against viral infections due to their ability to directly attack and kill infected cells. A Singapore study discovered the presence of virus-specific T-cell immunity in people who recovered from COVID-19 and SARS, as well as some healthy study subjects who had never been infected by either virus.

The study by scientists from the Duke-NUS School of Medicine, in close collaboration with the Yong Loo Lin School of Medicine at the National University of Singapore (NUS), (YLLSM), the Singapore General Hospital (SGH) and the Center National Infectious Diseases (NCID) was published in Nature. The findings suggest that infection and exposure to coronaviruses induce long-lasting memory T cells, which could aid in the management of the current pandemic and in the development of vaccines against COVID-19.

The team evaluated subjects who recovered from COVID-19 and discovered the presence of SARS-CoV-2-specific T cells in all of them, suggesting that T cells play an important role in this infection. Importantly, the team showed that patients who recovered from SARS 17 years after the 2003 outbreak still possess virus-specific memory T cells and showed cross-immunity to SARS-CoV-2.

“Our team also tested healthy uninfected individuals and found SARS-CoV-2-specific T cells in more than 50 percent of them. This could be due to cross-reactive immunity gained from exposure to other coronaviruses, such as those that They cause the currently unknown animal cold or coronaviruses. It is important to understand if this could explain why some people can better control the infection, “said Professor Antonio Bertoletti of the Duke-NUS ‘Emerging Infectious Diseases (EID) program, who is the corresponding author of this study.

Associate Professor Tan Yee Joo, Department of Microbiology and Immunology, NUS Yong Loo Lin School of Medicine, and Joint Senior Principal Investigator, Institute of Molecular and Cellular Biology, A * STAR added, “We have also initiated follow-up studies on the COVID -19 patients recovered, to determine if their immunity as shown in their T cells persists for an extended period of time. This is very important for the development of the vaccine and to answer the question about reinfection. ”

“While there have been many studies on SARS-CoV-2, there is still much that we still do not understand about the virus. What we do know is that T cells play an important role in the immune response against viral infections and should She will be evaluated for her role in fighting SARS-CoV-2, which has affected many people around the world. Hopefully, our discovery will take us one step closer to creating an effective vaccine, “said the associate professor. Jenny Low, Senior Consultant, Department of Infectious Diseases, SGH, and Duke-NUS EID program.

“NCID was encouraged by the tremendous support we received from many previous SARS patients for this study. Their contributions, 17 years after they were originally infected, helped us understand the mechanisms for long-lasting immunity against SARS-like viruses and its implications for developing better vaccines against COVID-19 and related viruses, “said Dr. Mark Chen I-Cheng, Head of the NCID Office of Research.

The team will conduct a larger study of exposed and uninfected subjects to examine whether T cells can protect against COVID-19 infection or alter the course of infection. They will also explore the potential therapeutic use of SARS-CoV-2-specific T cells.