claim: an infectivity-enhancing site on the sars-cov-2 spike protein is targeted by covid-19 patient antibodies.
evidence_1: enhancement of sars-cov-2 infection of primary b cells by covid-19 patient plasma.", "these findings suggest that the production of antibodies against sars-cov-2 infectivity-enhancing site could be considered as a possible exacerbating factors for covid-19 and that a spike protein lacking such antibody epitopes may be required for safe vaccine development, especially for individuals with pre-existing enhancing antibodies.", "covid-19 vaccine bnt162b1 elicits human antibody and th1 t-cell responses.", 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  "here we reported the observation of in vitro ade of sars-cov-2 entry into fcγrii receptor-bearing cells by plasma and antibodies from patients who recovered from covid-19.", "antibody responses to sars-cov-2 in patients with covid-19.")