claim: promotes cellular immunity to sars-cov-2 in severe covid-19 patients
evidence_1: however, compared to healthy controls, the percentages and absolute numbers of both nk cells and cd8+ t cells were significantly reduced, accompanied with decreased ifng expression in cd4+ t cells in peripheral blood from severe patients.", "our work thus indicates that covid-19 patients with severe symptoms are associated with defective cellular immunity, which not only provides insights on understanding the pathogenesis of covid-19, but also has implications in developing an effective vaccine to sars-cov-2.", 
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  "currently, though convalescent individuals have been shown with both cellular and humoral immune responses, there is very limited understanding on the immune responses, especially adaptive immune responses, in patients with severe covid-19.", "most notably, we failed in detecting sars-cov-2-specific ifng production by peripheral blood lymphocytes from these patients.")