Hamsters Protected from SARS-CoV-2 Delta Variant Challenge after Two Doses of Adjuvanted SARS-CoV-2 Recombinant Spike Protein (S-2P) and One Dose of Beta S-2P

J Infect Dis. 2022 Nov 1;226(9):1562-1567. doi: 10.1093/infdis/jiac153.

Abstract

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern negatively impact the effectiveness of vaccines. In this study, we challenge hamsters with the delta variant after 2- or 3-dose inoculations with SARS-CoV-2 vaccines constructed from stabilized prefusion spike proteins (S-2P) of Wuhan (W) and beta (B) variants. Compared to 3 doses of W S-2P, 2 doses of W S-2P followed by a third dose of B S-2P induced the highest neutralizing antibody titer against live SARS-CoV-2 virus and enhanced neutralization of omicron variant pseudovirus. Reduced lung live virus titer and pathology suggested that all vaccination regimens protect hamsters from SARS-CoV-2 delta variant challenge.

Keywords: COVID-19 vaccine; MVC-COV1901; SARS-CoV-2 vaccine; hamster challenge study; subunit vaccine; variant of concern.

MeSH terms

  • Adjuvants, Immunologic
  • Animals
  • Antibodies, Neutralizing
  • Antibodies, Viral
  • COVID-19 Vaccines* / immunology
  • COVID-19* / prevention & control
  • Cricetinae
  • SARS-CoV-2
  • Spike Glycoprotein, Coronavirus* / immunology

Substances

  • Adjuvants, Immunologic
  • Antibodies, Neutralizing
  • Antibodies, Viral
  • COVID-19 Vaccines
  • Spike Glycoprotein, Coronavirus
  • spike protein, SARS-CoV-2

Supplementary concepts

  • SARS-CoV-2 variants