Single-Cell and Plasma Proteomics Do Not Differentiate Patients With and Without SARS-CoV-2 Antigenemia in Convalescence in a Cohort of 100 Patients

Plasma samples obtained approximately 3 (<i>n</i> = 100) and 12 months (<i>n</i> = 78) after acute SARS-CoV-2 infection were tested for S1, spike, and N antigens. There were no significant differences in plasma proteins or single-cell protein expression levels on immune cells between those with and without plasma antigen detected.