Participants and Sample Collection
Informed consent was obtained prior to study initiation. This study was approved by the institutional review board at Cedars-Sinai Medical Center (protocol IRB numbers: 000 42267 and 000 00621). The study was conducted in accordance with the ethical guideline based on federal regulations and the common rule. The study was composed and written entirely by the authors who vouch for the results presented here.
Nineteen healthy controls, 134 patients with confirmed COVID-19 infection (of which, 14 received vaccination), and 38 vaccinated healthy individuals without history of SARS-CoV-2 infection were enrolled in the study with similar age and gender composition. The demographics of 134 patients are shown in Table 1. The time of blood draw from previously infected patients ranged from day 16 to day 388 (Median = 102) after reported SARS-CoV-2 infection by viral PCR and/or antibody test. The blood from vaccinated individuals was drawn 1-month post 2nd dose of Pfizer BNT162b2 mRNA vaccine. Fresh whole blood was collected in sodium heparinized tubes and stimulated with SARS-CoV-2 peptides overnight. Plasma obtained was stored at -80°C for SARS-CoV-2 Spike IgG analysis.