Lei et al. [2021] showed the spike protein in SARS-CoV-2 alone was enough to cause damage to lung vascular endothelium. The authors noted that their results suggest that “vaccination-generated antibody and/or exogenous antibody against S protein not only protects the host from SARS-CoV-2 infectivity but also inhibits S protein-imposed endothelial injury”. We show that there is no known mechanism by which the spike protein impairment of endothelial function could reduce vaccine safety, and that vaccine safety data clearly shows that the spike proteins in vaccines does not reduce vaccine safety. Overall, we conclude that spike proteins encoded by vaccines are not harmful, and may be beneficial to vaccine recipients.