Vaccination likely to be more protective against SARS-CoV-2 viral variants than natural infection

Antibodies generated by COVID-19 vaccines are more suited to recognizing viral variants than antibodies that arise from natural infection, according to a study by researchers at Stanford Medicine.

A key finding of the study might explain why: Regions in lymph nodes known as germinal centers — where antibodies are chosen and amplified by the immune system — are highly active for several weeks after vaccination. In contrast, the structure and cell composition of germinal centers are profoundly disrupted in people with fatal cases of COVID-19.

Vaccination generates a range of antibodies capable of responding to viral antigens beyond the original exposure. This greater breadth of antibodies suggests that vaccination is likely to be more protective against viral variants than immunity generated by previous infection."  

Scott Boyd, MD, PhD, associate professor of pathology

Boyd shares a senior authorship of the study, which was published online Jan. 24 in Cell, with Kari Nadeau, MD, PhD, the Naddisy Foundation Professor in Pediatric Food Allergy, Immunology, and Asthma. The lead authors are postdoctoral scholar Katharina Röltgen, PhD; former postdoctoral scholar Sandra Nielsen, PhD; clinical assistant professor of pathology Oscar Silva, MD, PhD; and life science researcher Sheren Younes, MD, PhD.

Response biased toward first viral exposure

The study also showed for the first time that a person's immune response to viral variants is strongly influenced by the version of the COVID-19 virus, known as SARS-CoV-2, first encountered by the immune system.

This phenomenon, known as imprinting, is similar to what is seen with influenza viruses that vary from season to season, and it creates a unique immune landscape for each individual. Prior exposures with different influenza viruses can either strengthen, or sometimes impair, responses to new influenza virus types. Understanding what imprinting means with regard to immunity against ever-evolving SARS-CoV-2 variants will be a focus of future investigation, and it could guide decisions about vaccine booster composition and timing, the scientists say.