AB1151 DOES PREDNISONE AFFECT COVID19 VACCINE T CELL RESPONSE? A STUDY OF VACCINE RESPONSE IN PATIENTS WITH IMMUNE SYSTEM DISEASES

Abstract

BackgroundA whole blood interferon gamma release assay (IGRA) based on the stimulation of SARS-Cov2-specific memory T cells using purified and full-lenght Spike and Nucleocapsid recombinant proteins was developed, together with anti-Spike antibody detection.ObjectivesTo study COVID19 vaccine cellular and humoral responses in patients with immune system diseases (ISD) and healthy controls.MethodsNon-vaccinated healthy individuals (n=103), SARS-Cov-2 infected individuals (n=9), and 104 samples from individuals having received COVID19 vaccine including 28 non-sars-cov2 infected patients with ISD diseases were included. Preliminary experiments were initiated using different platforms (ELISpot, IGRA, recombinant proteins or peptides) in order to evaluate Spike T cell response in volunteers vaccinated with BNT162b2 showing a S2>S1 poly-epitopic response.ResultsTwenty-eight patients (25 women, 3 men; mean age 59.1(±17,8)) with various ISD were investigated. These patients suffered from lupus (n=14), vasculitis (n=4), myositis (n=2), sarcoidosis (n=2), primary immunodeficiency (n=3), Sjögren’s syndrome (n=2) and pericarditis (n=1). Three patients had received 4 doses, 16 three doses, and 8 two doses of vaccine (Pfizer: n=25; Moderna n=1, Astra-Zeneca n=1). One patient refused the vaccination. The tests were performed 86.7 (±60.5) days after last vaccine dose. Ten patients were on prednisone (mean dose: 11,8 mg, median 7.5 mg, range: 5-40). Among those patients, 6 had only prednisone, 1 was also treated with belimumab, 3 with methotrexate (MTX) and 1 with azathioprine (AZA).Following COVID19 vaccination, humoral (100% in healthy vs 84.6% in ISD patients) and IGRA-Spike T cell (96% in healthy vs 59.7% in AI patients) responses took place with lower response reported among the ISD disease group (Figure 1). Humoral and cellular COVID19 vaccine responses significantly decrease after 100 days post vaccine.Figure 1.SARS-Cov2 humoral and T cell responses in non-vaccinated healthy individuals (n=103), SARS-Cov-2 infected individuals (n=9), and 104 samples from individuals having received COVID19 vaccine including 28 non-Sars-cov2 infected patients with ISD diseases. A- Anti-SARS-Cov2 Spike total IgM/IgG/IgA antibody (Ab) titers (BAU/mL) tested by ELISA. B- Whole blood IFN-γ release assay (IGRA) response to the full-length Spike recombinant protein (IGRA-Spike). C- Whole blood IGRA response to the nucleocapsid recombinant protein (IGRA-Nuc). Positivity cut-off (dot line) p values <0.05 are indicated when significant (ANOVA).5/5 vaccinated patients on CS alone, 2/5 vaccinated patients on corticosteroids with MTX/AZA/Belimumab and 3/17 other vaccinated patients (all being primary immunodeficiency patients) had no cellular response. Humoral and T cell responses were independent from sex and age.ConclusionAltogether, this ongoing study confirms the utility of the IGRA-Spike/-nucleocapsid assay coupled with serology in COVID19 vaccinated individuals and in particular in ISD patients treated with steroids, who may be at risk when the humoral protection decreases.ReferencesnoneDisclosure of InterestsNone declared