HUMORAL and CELLULAR RESPONSE to A THIRD BOOSTER DOSE SARS-COV-2 VACCINATION in PATIENTS with AUTOIMMUNE DISEASE: A CASE SERIES

ABSTRACT

Background: Patients with systemic rheumatic diseases (SRD) are at increased risk for viral infections and successful vaccination is crucial to combat COVID-19 pandemic in this population. However, reduced antibody responses have been described in a proportion of SRD individuals on immunosuppressant agents including mycophenolate (MMF). Objectives: We aimed to assess humoral and cellular response of SRD patients who received a booster SARS-CoV-2 vaccination. Methods: Twenty patients without history of COVID-19 infection (11 men, median age 58 years (range38-74), 12 on treatment with MMF (2gr daily) due to systemic sclerosis (n= 6), infammatory myositis (n=4) and systemic lupus erythematosus (n=2) and 8 on tumor necrosis factor-alpha inhibitors (anti-TNF) due to spondyloar-thritis (n=5), rheumatoid arthritis (n=2) and Bechet disease (n=1) were included. All were on monotherapy with anti-TNF except patient with Bechet. Patients on MMF discontinued treatment for 1 week after the booster dose whistle no treatment mod-ifcation was implemented in anti-TNF group. Serological response to vaccination was assessed using the Abbott SARS-CoV-2 IgG II Quant assay. Cellular immunity was estimated via interferon-γ produced by CD4+ and CD8+ T-lymphocytes in response to a SARS-CoV-2 peptide cocktail, with the SARS-CoV-2 ELISA Kit. Results: Nineteen patients (95%) demonstrated positive serological response following booster vaccine dose (Table 1). Only one female patient in MMF group failed to develop adequate levels of antibodies. The median antibody titers of patients under MMF and anti-TNF was 647.90 BAU/mL (range 0.71-4795.32 BAU/mL) and 542.98 BAU/mL (range 4.32-1391.33 BAU/mL) respectively. No statistically signif-cant difference was found between the two groups. Regarding cellular immunity a T-cell response was present in all patients on monotherapy with anti-TNF but only in 7/12 under MMF including the one with negative humoral response. Conclusion: We report sufficient immunogenicity following a third booster vaccine in patients with RSD on immunossupresive medications coupled by a strong cellular immune response particularly in patients on anti-TNF monotherapy. Per-rivaccination management of immunosuppressive therapy represents an important parameter of vaccine administration in patients with RSD.