COVID-19 mRNA vaccine induced antibody responses against three SARS-CoV-2 variants
Pinja Jalkanen, Pekka Kolehmainen, Hanni K. Häkkinen, Moona Huttunen, Paula A. Tähtinen, Rickard Lundberg, Sari Maljanen, Arttu Reinholm, Sisko Tauriainen, Sari H. Pakkanen, Iris Levonen, Arttu Nousiainen, Taru Miller, Hanna Välimaa, Lauri Ivaska, Arja Pasternack, Rauno Naves, Olli Ritvos, Pamela Österlund, Suvi Kuivanen, Teemu Smura, Jussi Hepojoki, Olli Vapalahti, Johanna Lempainen, Laura Kakkola, Anu Kantele, Ilkka Julkunen
Abstract
As SARS-CoV-2 has been circulating for over a year, dozens of vaccine candidates are under development or in clinical use. The BNT162b2 mRNA COVID-19 vaccine induces spike protein-specific neutralizing antibodies associated with protective immunity. The emergence of the B.1.1.7 and B.1.351 variants has raised concerns of reduced vaccine efficacy and increased re-infection rates. Here we show, that after the second dose, the sera of BNT162b2-vaccinated health care workers (n = 180) effectively neutralize the SARS-CoV-2 variant with the D614G substitution and the B.1.1.7 variant, whereas the neutralization of the B.1.351 variant is five-fold reduced. Despite the reduction, 92% of the seronegative vaccinees have a neutralization titre of >20 for the B.1.351 variant indicating some protection. The vaccinees' neutralization titres exceeded those of recovered non-hospitalized COVID-19 patients. Our work provides evidence that the second dose of the BNT162b2 vaccine induces cross-neutralization of at least some of the circulating SARS-CoV-2 variants.