Session Information
Session Type: ACR Concurrent Abstract Session
Session Time: 4:30PM-6:00PM
Background/Purpose: Autoimmune diseases are often preceded by subclinical serologic and functional abnormalities that predate diagnosis by several years. The insidious and progressive nature of these incomplete syndromes results in a lag in diagnosis, preventive and therapeutic strategies, and likely contributes to damage accrual.
Methods: : To explore possible markers of transition from incomplete Sjögren’s Syndrome (iSS) to complete Sjögren’s Syndrome (SS), 467 iSS patients were compared to 364 SS (SS) meeting AECG classification criteria in a multi-disciplinary sicca clinic. All subjects were evaluated for AECG classification measures, clinical and serological features (25 autoantibodies), and gene expression profiling of 64 interferon (IFN)-inducible genes. We developed an IFN-score based on the most informative 14 genes, which were differentially expressed (p<0.05, fold-change>2, and log2[SD(expression)]<1.75 for each group) in nine controls from previous microarray and RNASeq experiments with known high (n=4) and low (n=5) IFN-signature expression. A logistic regression model was created to calculate the probability of having a high interferon level for each iSS case; the resulting probability output is the IFN score.
Results: Nineteen iSS subjects had anti-Ro antibodies (4.1%), and 33 (7.1%) were biopsy (+); the remaining 415 had nonSS-sicca. Ro (+) iSS constituted a distinct subgroup from all Ro (-) iSS: they were younger (p=0.001), less white (p=1.95E10-7), more anti-La (+) (p=8.8E10-6), and had more hypergammaglobulinemia (p=0.02) and lymphopenia (p=0.009); 14/19 had extraglandular manifestations. These same statistically significant clinical differences were also observed when Ro (+) iSS to biopsy (+) iSS and Ro (-)/biopsy (-) iSS. Subsets of Ro (-) iSS subjects were (+) for other autoantibodies associated with SLE or Scleroderma: 14 had anti-Cenp-B and 10 had anti-dsDNA. Quantitatively, IFN-inducible gene expression occurs in a gradient: non-SS sicca patients have low IFN scores, biopsy (+)/Ro (-) have intermediate scores, and Ro (+) have high IFN scores, which are similar to those identified in autoantibody (+) pSS patients. High IFN-scores correlated with presence of any autoantibodies (p=1.08E-08), Ro (+) iSS (p=4.53E-06), and biopsy (+) iSS (p=6E-03), but only marginally with reduced salivary flow (p=0.018). There was no significant difference in IFN scores between SS and Ro (+) iSS, but SS had higher IFN scores than both biopsy (+) iSS and non-SS sicca (p=8.6E-3 and 1.95E-30, respectively).
Conclusion: Patients with iSS may represent a forme frustre of SS, but it is plausible that some subsets, in particular Ro (+) iSS and dsDNA(+) iSS, will progress to SS, SLE, or overlap syndromes, respectively. The fact that they present similar IFN-signatures as those observed in SS further supports this notion, and therefore, iSS patients warrant careful follow up to characterize the transition to full-blown SS. Understanding the early events of disease has the strongest potential to lead to improvements in prevention, early diagnosis, and therapeutics.
To cite this abstract in AMA style:
Rasmussen A, Lessard CJ, Adrianto I, Wiley GB, Stone DU, Kaufman CE, Radfar L, Lewis DM, Young SK, Weisman MH, Wallace DJ, Venuturupalli S, Segal BM, Ice JA, Anaya JM, Rohrer MD, Gopalakrishnan R, Houston GD, Chodosh J, Hughes PJ, Rhodus NL, Kelly JA, Grundahl K, Hefner K, Scofield RH, Sivils KL. Characterization of Early and Progressive Autoimmunity in Sjogrens Syndrome: The Incomplete Sjogrens Syndrome Model [abstract]. Arthritis Rheumatol. 2015; 67 (suppl 10). https://acrabstracts.org/abstract/characterization-of-early-and-progressive-autoimmunity-in-sjogrens-syndrome-the-incomplete-sjogrens-syndrome-model/. Accessed .« Back to 2015 ACR/ARHP Annual Meeting
ACR Meeting Abstracts - https://acrabstracts.org/abstract/characterization-of-early-and-progressive-autoimmunity-in-sjogrens-syndrome-the-incomplete-sjogrens-syndrome-model/