Preserved Cellular Immunity Upon Influenza Vaccination in Most Patients with Common Variable Immunodeficiency

BACKGROUND: Vaccination against influenza is recommended for patients with common variable immunodeficiency (CVID), although humoral immune responses in these patients are impaired and the evidence of effective T-cell responses in CVID is not well established. OBJECTIVE: To determine plasmablast and T-cellular vaccination responses against influenza in patients with CVID. METHODS: Patients with CVID and healthy controls were vaccinated with the quadrivalent vaccine Influsplit Tetra 2018/2019. Before and 1 week after vaccination plasmablasts and circulating inducible costimulator-expressing T follicular helper cells were measured to determine positive vaccine responses in these patients. In addition, antigen-specific T cells were determined by their upregulation of CD25 and OX40 after in vitro restimulation with the vaccine. RESULTS: Most healthy controls but only 1 patient with CVID mounted a positive humoral immune response, measured by an increase in plasmablasts 1 week after vaccination. In contrast, most patients with CVID showed an increase in inducible costimulator(+) T follicular helper cells and/or an increase in antigen-specific CD25(+)OX40(+) T cells 1 week after vaccination, demonstrating a positive T-cellular immune response. CONCLUSIONS: Despite the remaining challenge of accurately assessing the complexity of T-cell responses, the recommendation of vaccinating patients with CVID against influenza is reasonable. (C) 2020 American Academy of Allergy, Asthma & Immunology.