Increased memory B cell potency and breadth after a SARS-CoV-2 mRNA boost

Abstract The Omicron variant of SARS-CoV-2 infected many vaccinated and convalescent individuals 1–3 . Despite the reduced protection from infection, individuals who received three doses of an mRNA vaccine were highly protected from more serious consequences of infection 4 . Here we examine the memory B cell repertoire in a longitudinal cohort of individuals receiving three mRNA vaccine doses 5,6 . We find that the third dose is accompanied by an increase in, and evolution of, receptor-binding domain (RBD)-specific memory B cells. The increase is due to expansion of memory B cell clones that were present after the second dose as well as the emergence of new clones. The antibodies encoded by these cells showed…

• HH
  Howard Hughes Medical Institute
• NI
  National Institutes of Health

  Awards: R37-AI64003, AI111825, R01AI78788, P01-AI138398-S1, COVID-19, TR001866, UL1 TR001866, UL1-TR001866, 2U19AI111825
• NC
  National Center for Advancing Translational Sciences

  Award: TR001866