OP0131 Innate lymphoid cells correlate with disease activity and bone remodelling in psoriatic arthritis. (12th June 2018)

• Record Type: Journal Article
• Authors: Soare, A.; Weber, S.; Maul, L.; Rauber, S.; Gheorghiu, A.M.; Houssni, I.; Kleyer, A.; Luber, M.; Rech, J.; Schett, G.; Distler, J.; Ramming, A.
• Is Part Of: Annals of the rheumatic diseases. Volume 77(2018)Supplement 2
• Page Start: 116
• Page End: 116
• Publication Date: 2018-06-12
• Subjects: Rheumatism -- Periodicals; 616.723005
• DOI: 10.1136/annrheumdis-2018-eular.7177
• Languages: English
• ISSNs: 0003-4967

Abstract

Abstract : Background: Evaluation of actual immunopathology in psoriatic arthritis (PsA) is challenging. Current composite measures approved for PsA are very useful tools to assess disease activity in clinical routine. Nonetheless, because of subjective patients' estimations that widely affect the scoring, in particular the distinction between remission and low disease activity is a common question of debate. Innate lymphoid cells (ILC) subsets may couple different aspects of PsA disease activity. Objectives: To address whether PsA is associated with an altered composition of innate lymphoid cells and whether such changes are associated with disease activity and structural damage in PsA. Methods: 124 patients satisfying the Classification Criteria for Psoriatic Arthritis (CASPAR) and 26 healthy volunteers were enrolled in the study. Information regarding clinical features, laboratory parameters were collected and disease activity score 28 (DAS28), disease activity in psoriatic arthritis (DAPSA), minimal disease activity score (MDA) were calculated. MRI and high-resolution peripheral CT were taken and PsA MRI score (PsAMRIS) was assessed. Flow cytometric analysis was performed and IFNg-producing ILC1s, IL-4/IL-5-producing ILC2s and IL-17/IL-22-producing ILC3s were identified among ILCs. Multivariate linear regression and Receiver-Operating Characteristic (ROC) Curve analysis was performed using the IBM SPSS Statistics software. Results: Total number of circulating ILCs were increased in PsA patients compared to healthy controls (p<0, 001). Linear regression analyses of the relationship between disease activity and circulating ILC counts showed that ILC2 negatively and ILC1 and ILC3 positively correlated with DAPSA score. The strongest correlation was observed when the ratio of ILC2 to ILC3 was analysed (R=-0.5709; p<0.0001). ILC2/3 ratio was also reduced in patients with active psoriatic skin disease, presence of enthesitis or a history of concomitant uveitis. Extend of synovitis or tenosynovitis or presence of bone erosions or osteophytes on MRI was inversely correlated with the ILC2/3 ratio (R=-0.6753; p<0.0001, R=-0.5828; p=0.0011 and p<0.001 respectively). Consistently, presence of erosions and/or osteoproliferation assessed by HR-pQCT was correlated with a significant lower ILC2/3 ratio. Furthermore, ROC Curve was used to test the performance of the ILC2/3 ratio as marker in differentiating between remission and disease activity of PsA. Indeed, a cut-off 0.57 exhibited highest sensitivity (92.9%) and a 84.7% specificity in identifying remission. Conclusions: The ILC2/3 ratio correlates with various facets of PsA manifestations and might be a useful tool to evaluate disease activity in PsA patients. Disclosure of Interest: None declared