Background: There is an urgent need to assess the levels of protection generated by natural infection or SARS-CoV-2 vaccines, especially in individuals professionally exposed. Measuring T-cell responses may complement antibody tests currently in use as correlates of protection. Our aim was to assess the feasibility of a validated assay of T-cell responses applicable to large number of samples. Methods: Twenty health-care-workers (HCW) were included. Antibody test to SARS-CoV-2 N and S-proteins in parallel with a commercially available whole-blood-interferon-gamma-release-assay (IGRA) to S-peptides and two detection methods, CLIA and ELISA were determined. Results: IGRA test detected T-cell responses in naturally exposed and vaccinated HCW already after first vaccination dose. The correlation by the two detection methods was very high (R>0.9) and sensitivity and specificity ranged between 100 and 86% and 100-73% respectively. Even though there was a very high concordance between antibody and the IGRA assay in the ability to detect immune response to SARS-CoV-2, there was a relatively low quantitative correlation. In the small group primed by natural infection, one vaccine dose was sufficient to reach immune response plateau. IGRA was positive in one, with Ig(S) antibody negative vaccinated immunosuppressed HCW illustrating another advantage of the IGRA-test. Conclusion: Whole-blood-IGRA-tests amenable to automation and constitutes a promising additional tool for measuring the state of the immune response to SARS-CoV-2; they are applicable to large number of samples and may become a valuable correlate of protection to COVID-19, particularly for

Background: Recognition of specific allergens triggering immune response is key for the appropriate prescription of allergen-specific immunotherapy (SIT). This study aimed at evaluating the impact of using the commercially available microarray ImmunoCAP TM ISAC 112 (Thermo Fisher Scientific) on the etiological diagnosis and SIT prescription compared to the conventional diagnostic methods in patients with allergic rhinitis/rhinoconjunctivitis and/or asthma. Methods: 300 patients with respiratory allergic disease, sensitized to three or more pollen aeroallergens from different species, as assessed by skin prick-test (SPT) and specific IgE assays (sIgE), were included in this multicentric, prospective observational study. SPT and a blood test were performed to all patients. Total serum IgE, sIgE (ImmunoCAP TM) for allergens found positive in the SPT and sIgE allergen components (ImmunoCAP TM ISAC 112) were measured. Results: According to SPT results, the most prevalent pollen sensitizers in our population were Olea europaea followed by grass, Platanus acerifolia and Parietaria judaica. The molecular diagnosis (MD) revealed Ole e 1 as the most prevalent pollen sensitizer, followed by Cup a 1, Phl p 1, Cyn d 1, Par j 2, Pla a 1, 2, and 3 and Phl p 5. Immunotherapy prescription changed, due to MD testing, in 51% of the cases, with an increase of prescription of SIT from 39% to 65%. Conclusion: The identification of the allergen eliciting the respiratory disease is essential for a correct immunotherapy prescription. The advances in allergen characterization using methods such as the commercial microarray ImmunoCAP TM ISAC 112 can help clinicians to improve SIT prescription.