Immune responses after influenza vaccination in patients of primary Sj?gren´s syndrome

Objectives: Influenza vaccination is effective in preventing infections in most people. This study aimed to assess the changes of immune responses in primary Sj?gren´s Syndrome (pSS) patients after influenza vaccination and determine the safety of influenza vaccination.
Methods: A total of 17 patients with pSS and 16 healthy controls (HCs) were included. Peripheral mononuclear cells were analysed by flow cytometry. Vaccine-specific antibodies were determined by ELISA. Clinical features and serological responses were monitored.
Results: The percentages of T follicular helper cell (Tfh) were significantly elevated in HCs after vaccination (P=0.0005), while no significant differences in the levels of Tfh in pSS patients were identified (P=0.1748). The proportions of Th2 cells were significantly decreased after vaccination in both pSS patients and HCs (P<0.05). In contrast, the percentages of Th1 cells and Th17 cells were significantly increased after vaccination in pSS patients (P<0.05), while no significant differences in the percentages of Th1 and Th17 cells were identified in HCs (P>0.05), although a trend towards higher levels of Th1 cells was observed (P=0.0830). No significant changes in the proportions of memory B cells and plasmablasts were observed after vaccination. Patients with pSS developed higher levels of vaccine-specific IgGs compared with HCs (P=0.001). No significant changes in disease manifestations and laboratory parameters were observed after vaccination. No increased vaccination related adverse effect was observed in pSS.
Conclusion: Our findings suggest the feasibility of applying influenza vaccines to patients with pSS, raising awareness for vaccination among the rheumatology community and involved healthcare professionals.