Accuracy of QuantiFERON SARS-CoV-2 research use only assay and characterization of the CD4+ and CD8+ T cell-SARS-CoV-2 response: comparison with a homemade interferon-γ release assay
Alessandra Aiello, Andrea Coppola, Valentina Vanini, Linda Petrone, Gilda Cuzzi, Andrea Salmi, Anna Maria Gerarda Altera, Carla Tortorella, Gina Gualano, Claudio Gasperini, Palma Scolieri, Alessia Beccacece, Serena Vita, Vincenzo Bruzzese, Roberto Lorenzetti, Fabrizio Palmieri, Emanuele Nicastri, Delia Goletti
Abstract
OBJECTIVES: In this study, we aimed to characterize the SARS-CoV-2-specific T cell response detected by the QuantiFERON SARS-CoV-2 research use only assay in terms of accuracy and T cell subsets involved compared with a homemade interferon (IFN)-γ release assay (IGRA). METHODS: We evaluated T cell response by the standardized QuantiFERON SARS-CoV-2 tubes (antigen [Ag]1 and Ag2) and a homemade IGRA quantifying IFN-γ response to SARS-CoV-2 spike peptides (homemade-IGRA-SPIKE test). We evaluated the T cell subsets mediating the specific response using flow cytometry. RESULTS: T cell subset. CONCLUSION: T cells. A lower number of responders is found compared with the homemade-IGRA-SPIKE test, likely because of the different peptide composition.