Study Compares Antibody Evolution in Convalescent and Vaccine-Elicited Individuals

Aug, 2021 - By WMR

A team of researchers from the Rockefeller University, U.S. conducted a study that stresses on antibody evolution after vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

The onset of COVID-19, caused by SARS-CoV-2, has changed the global healthcare structure which claimed the lives of over 4.2 million people across the globe since its inception in December 2019. In the current study, the researchers studied about antibody evolution following vaccination with either the Pfizer-BioNTech or Moderna vaccine. They also studied the antibodies generated through natural infection. They found that antibodies generated by natural infection have greater potential in comparison to the antibodies elicited by vaccination. In this context, it is important to mention that B-cell responses, following SARS-CoV-2 infection, continue to evolve for at least a year. The memory B-cells increase broadly with potent antibodies resistant to new variants of SARS-CoV-2. Thus, the researchers found that vaccinating those individuals who recovered from COVID-19 infection possess high levels of plasma neutralizing activity against evolving new variants of SARS-CoV-2. The researchers observed approximately 2 times increase in the receptor binding affinity (RBD) of conserved clonal antibodies between two and five months after vaccination in those individuals who did not contract the virus earlier. However, they found that in case of convalescent individuals, there was a 24-fold increase in the conserved clonal antibodies between 1.3 and 6.2 months. More importantly, previous studies have confirmed that neutralizing breadth of memory antibodies in convalescent individuals derived from conserved clones increase with time after infection.

The researchers concluded that there is difference in antibody evolution in convalescent individuals and vaccinated individuals. They also revealed that boosting vaccinated individuals with Pfizer-BioNtech vaccine or Moderna vaccine would increase quantitatively plasma neutralizing activity but fail to obtain the qualitative benefit obtained by vaccinating convalescent individuals.