Antibodies to SARS-CoV-2 in patients with primary immunodeficiencies treated with nonspecific immunoglobulins N-reactive antibodies are readily increased upon infection [5] and, in convalescent patients, occasionally may even dominate the response [6].We reasoned that if these patients had recently become infected, they should have a prominent cellular response (mediated by T lymphocytes) against different viral antigens. However, when we studied the CD4 SP + sp and CD8 SP + sp T cell-mediated responses against epitopes from SARS-CoV-2 S1 and S2 subunits, we could not detect interferon gamma production in any of the patients ruling out a recent infection as a source of the antibodies. [Extracted from the article]