OA11 Juvenile Sjögren’s syndrome is characterised by dysregulated of B and T memory cell frequencies: a pilot immunophenotyping analysis of this rare disease phenotype

Abstract Background/Aims Sjögren’s syndrome (SS) is an autoimmune rheumatic disease characterised by dryness resulting from chronic lymphocytic infiltration of the exocrine glands and extra glandular manifestations such as arthritis, anemia, fatigue. The more frequent in women aged 30-50. However, rare cases, starts childhood, known juvenile SS (jSS). Children have different clinical compared to adults, with being less common, making diagnosis very challenging. Our aim investigate depth immune cell profile patients jSS their cytokine for better understanding pathogenesis. Methods Peripheral blood was collected a cohort (n = 10) age sex-matched healthy controls (HC) 10). None had received B-cell depletion therapy. immune-phenotyping 29 immune-cell subsets, including B T cells, performed using flow cytometry we reported previously adult-onset SS. Data were analyzed multiple t-tests adult phenotype. A panel 15 serum cytokines associated pathology measured Luminex, detect statistically significant differences between HCs. Results Patients average 18 years (range 16-21) onset at 14 12-18). 60% anti-Ro autoantibodies 50% anti-La autoantibodies. altered age-matched (HCs) (mean years, range 15-25). In compartment, higher frequencies total CD19+ cells (p 0.0044), naïve (CD19+IgD+CD27-) 0.0183) bm2 (CD19+IgD+CD38+) 0.0490) whereas memory subsets early bm5 (CD19+IgD-CD38+) late (CD19+IgD-CD38-) significantly reduced 0.0249 p 0.0117, respectively). Interestingly, CD4+ central (CD4+CD27+CD45RA-) <0.0001) but effector (CD4+CD27-CD45-) memory-re-expressing-CD45RA (EMRA, CD4+CD27-CD45RA+) T-cell elevated 0.0171 0.0002 There also increase CD8+CD25-CD127+ responders 0.0392) versus Serum levels APRIL CCL8 jSS. Conclusion This first pilot study investigating line our previous studies adults detected suggesting immunological rationale use similar therapies across age. found specific dysregulation responder CD8+ subpopulation HCs, which requires further investigation. data could indicate ongoing homeostasis mature B-cells activation cells. Disclosure L. Martin-Gutierrez: None. H. Peckham: A. Radziszewska: J. Peng: O. Nettey: E. Jury: C. Ciurtin: