Expression of SARS coronavirus 1 spike protein from a herpesviral vector induces innate immune signaling and neutralizing antibody responses

Virology. 2021 Jul;559:165-172. doi: 10.1016/j.virol.2021.04.006. Epub 2021 Apr 21.


SARS coronavirus 1 (SARS-CoV-1) causes a respiratory infection that can lead to acute respiratory distress characterized by inflammation and high levels of cytokines in the lung tissue. In this study we constructed a herpes simplex virus 1 replication-defective mutant vector expressing SARS-CoV-1 spike protein as a potential vaccine vector and to probe the effects of spike protein on host cells. The spike protein expressed from this vector is functional in that it localizes to the surface of infected cells and induces fusion of ACE2-expressing cells. In immunized mice, the recombinant vector induced antibodies that bind to spike protein in an ELISA assay and that show neutralizing activity. The spike protein expressed from this vector can induce the expression of cytokines in an ACE2-independent, MyD88-dependent process. These results argue that the SARS-CoV-1 spike protein intrinsically activates signaling pathways that induce cytokines and contribute directly to the inflammatory process of SARS.

Keywords: Cytokines; Herpes simplex virus; SARS coronavirus.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Neutralizing / blood
  • Antibodies, Neutralizing / immunology*
  • Antibodies, Viral / blood
  • Antibodies, Viral / immunology
  • Cell Fusion
  • Cell Line
  • Cytokines / immunology
  • Genetic Vectors
  • Herpesvirus 1, Human / genetics*
  • Humans
  • Immunity, Innate*
  • Mice
  • Severe acute respiratory syndrome-related coronavirus / genetics
  • Severe acute respiratory syndrome-related coronavirus / immunology*
  • Signal Transduction
  • Spike Glycoprotein, Coronavirus / genetics
  • Spike Glycoprotein, Coronavirus / immunology*
  • Spike Glycoprotein, Coronavirus / metabolism
  • Vaccines, Virus-Like Particle / immunology
  • Viral Vaccines / immunology


  • Antibodies, Neutralizing
  • Antibodies, Viral
  • Cytokines
  • Spike Glycoprotein, Coronavirus
  • Vaccines, Virus-Like Particle
  • Viral Vaccines
  • spike glycoprotein, SARS-CoV