SAT0205 Blys up-regulation and salivary clonal B-cell expansion characterize sjögren's syndrome-related lymphoproliferative disorders and correlate with the new ESSDAI score. (23rd January 2014)

• Record Type: Journal Article
• Authors: Quartuccio, L.; Salvin, S.; Fabris, M.; Maset, M.; Corazza, L.; Pontarini, E.; Isola, M.; De Vita, S.
• Is Part Of: Annals of the rheumatic diseases. Volume 71(2012)Supplement 3
• Page Start: 541
• Page End: 541
• Publication Date: 2014-01-23
• Subjects: Rheumatism -- Periodicals; 616.723005
• DOI: 10.1136/annrheumdis-2012-eular.3152
• Languages: English
• ISSNs: 0003-4967

Abstract

Abstract : Background: Primary Sjögren's syndrome (SS) is characterized by an increased risk of lymphoma in patients with prelymphomatous manifestations (i.e., myoepithelial sialadenitis (MESA) or mixed cryoglobulinemia). Increased levels of B-lymphocyte stimulator (BLyS) characterize different autoimmune diseases, and in particular SS. Objectives: Serum BLyS levels in SS-related B-cell lymphoproliferative disorders were studied, by integrating the results with the disease activity score and molecular analyses of B-cell expansion on the salivary glands. Methods: 76 primary SS patients were studied. SS patients were distributed into four groups: a) SS without any lymphoproliferative disorder (n=34); b) SS with cryoglobulinemic vasculitis (CV) without overt lymphoma (n=14); c) SS with MESA (n=12); d) SS with overt lymphoma (n=16). Serum BLyS and molecular analyses of B cells in the salivary gland tissues, when available, were performed. Patients with SS and persistent parotid swelling underwent parotid biopsy. Results: BLyS differed between SS subgroups, higher levels being documented in patients with B-cell lymphoproliferative disorders (as a whole group) versus SS without (1.85 (0.45-4.12) ng/ml vs 1.12 (0.56-1.98) ng/ml; p<0.0001), and a significant difference was also observed between SS with frank lymphoma and SS without any lymphoproliferative disorder (p=0.0002). BLyS levels significantly correlated with the EULAR SS disease activity index (ESSDAI) (r=0.62, p<0.0001, Spearman's test). Higher ESSDAI scores were observed in SS with overt lymphoma if compared with SS without a lymphoproliferative disorder [22.5 (16-35) vs 4.0 (0-16), p<0.0001], or if compared with SS with CV [22.5 (16-35) vs 15.5 (7-25), p=0.005], who showed an intermediate result. Clonal B-cell expansion in the salivary glands rather than polyclonal B-cell expansion was associated with higher BLyS levels [1.98 (0.45-4.12) vs 1.15 (0.56-3.25) ng/ml; p=0.013)]. ESSDAI score was also significantly associated with B-cell clonal expansion in the salivary glands [21.0 (0-35) vs 6.0 (0-37), p=0.0003] and this association was confirmed even after excluding SS patients with lymphoma [17.5 (0-35) vs 6.0 (0-37), p=0.02]. Conclusions: Higher BLyS levels and clonal B-cell expansion characterizes SS with B-cell lymphoproliferative disorders, even at pre-lymphomatous stages. This subgroup of SS patients showed the highest ESSDAI scores. This is the biologic rationale for targeting both the clonal B-cell expansion and the BLyS overproduction in SS patients with a B-cell lymphoproliferative disorder and high disease activity. Disclosure of Interest: None Declared