Arpita Myles

Soluble Receptor for Advanced Glycation Endproducts Is Decreased in Patients with Juvenile Idiopathic Arthritis (ERA Category) and Inversely Correlates with Disease Activity and S100A12 Levels

Objective. Membrane-bound receptor for advanced glycation endproducts (mRAGE) is overexpressed in response to increasing concentrations of its ligand (e.g., S100A12) and triggers an inflammatory immune response. In contrast, soluble RAGE (sRAGE) acts as a decoy receptor and downmodulates inflammation. Decreased sRAGE levels are associated with autoimmune diseases; however, limited data are available in juvenile idiopathic arthritis (JIA). We studied sRAGE levels in patients with JIA [enthesitis-related arthritis (ERA) category]. Methods. sRAGE levels were estimated in the serum of patients with ERA JIA (n = 101), systemic-onset JIA and polyarticular JIA (n = 10 each), and healthy controls (n = 45). Synovial fluid (SF) sRAGE was measured in patients with ERA, rheumatoid arthritis, reactive arthritis, and osteoarthritis (n = 10). Levels of S100A12 were also measured. Twenty-four patients with ERA were followed for 4 months. Disease activity was assessed by swollen joint count (SJC), tender joint count (TJC), and erythrocyte sedimentation rate (ESR). All levels are expressed as median (range). Results. The serum sRAGE (pg/ml) level was significantly lower in patients compared to healthy controls [515 (64–1887) vs 1542 (627–3159); p < 0.0001]. In paired samples, SF had lower levels compared to corresponding plasma level [102 (51–799) vs 481 (134–1006); p < 0.0001]. The level of S100A12 (ng/ml) was higher in SF (1042; 573–1415) than serum (638; 208–779). Serum sRAGE correlated negatively with S100A12 levels (r = −0.474; p < 0.01.), ESR (r = −0.306; p < 0.01), and SJC (r = −0.237; p < 0.05), but not with TJC (r = −0.134; p = NS). The levels of sRAGE remained stable over time in patients with stable disease. Conclusion. Levels of sRAGE are reduced in patients with ERA and correlate negatively with disease activity and S100A12 levels. sRAGE may be a modulator of inflammation in these patients.

TLR4 endogenous ligand MRP8/14 level in enthesitis-related arthritis and its association with disease activity and TLR4 expression

OBJECTIVE Enthesitis-related arthritis (ERA) is an inflammatory disease of childhood that lacks autoantibodies. Overexpression of surface-expressed Toll-like receptors (TLRs) has been found in ERA. Myeloid-related proteins (MRPs) 8 and 14 are calcium binding proteins that act as an endogenous ligand of TLR4. MRP8/14 levels are elevated in patients with systemic-onset arthritis. Thus we studied the role of MRP8/14 in ERA. METHODS The study enrolled patients with ERA. Plasma and SF levels of MRP8/14 were measured by ELISA and TLR4 expression on peripheral blood and SF monocytes was measured by two-colour flow cytometry. Control plasma samples were collected from 48 blood bank donors. RESULTS Of the 69 patients, 67 were male, with a mean age of 15.2 (s.d. 2.7) years and a disease duration of 5 (s.d. 3) years. Median plasma levels of MRP8/14 were higher in patients (10 862.3 ng/ml) than controls (4426.1 ng/ml, P < 0.0001). Patients with active disease (11 669.5 ng/ml) had higher levels as compared with inactive disease (4421.8 ng/ml, P < 0.0001). Plasma MRP8/14 levels decreased on follow-up after 3 months only in patients who responded to treatment (P = 0.012). MRP8/14 levels were negatively correlated with the frequency of CD14(+)TLR4(+) cells (r = -0.372, P = 0.02). MRP8/14 levels were higher in SF as compared with plasma (15 858.45 ng/ml, P = 0.024). The frequency of CD14(+)TLR4(+) cells was higher in SF as compared with peripheral blood. CONCLUSION MRP8/14 levels are increased in the plasma of ERA patients and are higher in those with active disease and the levels decrease in patients who respond to treatment, suggesting that it may be a good biomarker during follow-up.

Soluble CD25 in serum: a potential marker for subclinical macrophage activation syndrome in patients with active systemic onset juvenile idiopathic arthritis.

Laboratory and immunological abnormalities seen in overt macrophage activation syndrome (MAS) may be observed in patients with untreated new onset systemic onset juvenile idiopathic arthritis (SoJIA). We investigated the prevalence of clinical and traditional laboratory markers of MAS as well as soluble CD163 and soluble interleukin (IL)‐2Rα (CD25) in active SoJIA patients.

Levels of Serum Matrix Metalloproteinase-3 Correlate with Disease Activity in the Enthesitis-related Arthritis Category of Juvenile Idiopathic Arthritis

Objective. Serum matrix metalloproteinase-3 (MMP-3) has been shown to reflect disease activity in ankylosing spondylitis (AS) and rheumatoid arthritis. Elevated levels have been found in juvenile idiopathic arthritis (JIA). In the enthesitis-related arthritis category of JIA (JIA-ERA), we studied whether serum MMP-3 levels and ratios of MMP-3/tissue inhibitor of metalloproteinase (TIMP-1) are correlated with disease activity and whether they are sensitive to change in disease activity. Methods. A total of 54 patients with JIA-ERA (International League of Associations for Rheumatology criteria) were enrolled for study. Baseline disease activity measures included tender and swollen joint counts, Maastricht AS Enthesitis Score, Bath AS Disease Activity Index (BASDAI), Bath AS Functional Index (BASFI), patient assessment of pain and global disease activity, physician assessment of global disease activity, and erythrocyte sedimentation rate (ESR). Serum MMP-3 and TIMP-1 levels were measured using ELISA. A group of 24 patients were followed up for longitudinal study. Results. The mean age of 54 patients (48 males) at disease onset was 11.8 ± 4.19 years and duration of disease was 5.2 ± 4.3 years. Median ESR was 65 mm/h (range 46.5–97) and median BASDAI was 3.4 (range 2.5–4.7). Median MMP-3, TIMP-1, and MMP-3/TIMP-1 ratio were 50.4 ng/ml (IQR 13.0–193.8), 228.9 ng/ml (IQR 108.2–290.4), and 0.3 (IQR 0.07–1.13), respectively. At inclusion MMP-3 levels correlated directly with various disease activity measures: tender joint count (TJC; r = 0.60), swollen joint count (SJC; r = 0.45), BASFI (r = 0.29), BASDAI (r = 0.32), ESR (r = 0.49), physician global assessment (r = 0.40), patient visual analog scale for pain (r = 0.28), and patient global assessment (r = 0.38; all p < 0.05). MMP-3/TIMP-1 ratio correlated only with TJC (r = 0.51), SJC (r = 0.39), and ESR (r = 0.34; p < 0.05). At followup, change in MMP-3 correlated with changes in TJC (r = 0.42) and SJC (r = 0.44; p < 0.05), while change in ESR did not correlate with change in any disease activity measure. Conclusion. MMP-3 levels are a good marker for disease activity in JIA-ERA.

Membrane-Bound Toll-Like Receptors are Overexpressed in Peripheral Blood and Synovial Fluid Mononuclear Cells of Enthesitis-Related Arthritis Category of Juvenile Idiopathic Arthritis (JIA–ERA) Patients and Lead to Secretion of Inflammatory Mediators

We examined expression and function of TLRs in enthesitis-related arthritis (ERA) patients. RNA levels of TLR1, TLR3, and TLRs 5–8 were measured in 24 ERA peripheral blood mononuclear cells (PBMC), 18 synovial fluid mononuclear cells (SFMC), and IRAK1, IRAK4, TRIF, TRAF3, and TRAF6 in 18 PBMC and 10 SFMC. IL-6 and IL-8 were measured in supernatants from ERA PBMC (n = 7), SFMC (n = 3), and healthy PBMC (n = 5) cultured with ligands for TLR1/2 (Pam 3-cys), TLR3 (poly I:C), TLR5 (flagellin), and TLR2/6 (zymosan). TLRs 1, 3, 5, and 6 were measured in whole blood (n = 20 ERA, seven healthy) and SFMC (n = 2) by flow cytometry. ERA PBMC compared to healthy PBMC and SFMC compared to ERA PBMC had higher RNA expression of TLR1, TLR3, TLR5, TLR6, IRAK1, IRAK4, TRIF, TRAF3, and TRAF6. TLR7 and TLR8 RNA expression was similar in all study groups. IL-6 and IL-8 levels were higher in stimulated ERA SFMC compared to ERA PBMC and in ERA PBMC compared to control PBMC. TLRs 1, 3, and 6 were also overexpressed at the protein level.

PReS-FINAL-2020: Cell type specific transcriptome analysis in patients with enthesitis related arthritis category of juvenile idiopathic arthritis (JIA-ERA)

Enthesitis Related Arthritis Category of Juvenile Idiopathic Arthritis (JIA-ERA) is the most common category of JIA seen in Asian Indians. Transcriptome analysis is a useful tool to analyse pathways involved in disease pathogenesis. Peripheral blood mononuclear cells (PBMC) and SFMC analysis showed involvement of innate immune cells in JIA-ERA. However PBMC/SFMC have variable number of different cells and that can affect interpretation. No data is available on cell type specific transcriptome analysis of blood and synovial fluid in children with JIA-ERA.

Soluble Receptor for Advanced Glycation End Products (sRAGE) is decreased in patients with Juvenile Idiopathic Arthritis (ERA category) and inversely correlates with disease activity and S100A12 levels.

Objective. Membrane-bound receptor for advanced glycation endproducts (mRAGE) is overexpressed in response to increasing concentrations of its ligand (e.g., S100A12) and triggers an inflammatory immune response. In contrast, soluble RAGE (sRAGE) acts as a decoy receptor and downmodulates inflammation. Decreased sRAGE levels are associated with autoimmune diseases; however, limited data are available in juvenile idiopathic arthritis (JIA). We studied sRAGE levels in patients with JIA [enthesitis-related arthritis (ERA) category]. Methods. sRAGE levels were estimated in the serum of patients with ERA JIA (n = 101), systemic-onset JIA and polyarticular JIA (n = 10 each), and healthy controls (n = 45). Synovial fluid (SF) sRAGE was measured in patients with ERA, rheumatoid arthritis, reactive arthritis, and osteoarthritis (n = 10). Levels of S100A12 were also measured. Twenty-four patients with ERA were followed for 4 months. Disease activity was assessed by swollen joint count (SJC), tender joint count (TJC), and erythrocyte sedimentation rate (ESR). All levels are expressed as median (range). Results. The serum sRAGE (pg/ml) level was significantly lower in patients compared to healthy controls [515 (64–1887) vs 1542 (627–3159); p < 0.0001]. In paired samples, SF had lower levels compared to corresponding plasma level [102 (51–799) vs 481 (134–1006); p < 0.0001]. The level of S100A12 (ng/ml) was higher in SF (1042; 573–1415) than serum (638; 208–779). Serum sRAGE correlated negatively with S100A12 levels (r = −0.474; p < 0.01.), ESR (r = −0.306; p < 0.01), and SJC (r = −0.237; p < 0.05), but not with TJC (r = −0.134; p = NS). The levels of sRAGE remained stable over time in patients with stable disease. Conclusion. Levels of sRAGE are reduced in patients with ERA and correlate negatively with disease activity and S100A12 levels. sRAGE may be a modulator of inflammation in these patients.