Elevated levels of IL-37 correlate with T cell activation status in rheumatoid arthritis patients.

OBJECTIVE: To assess the association between serum levels of IL-37 in rheumatoid arthritis patients and percentage of peripheral blood T lymphocytes expressing the activation marker CD26 and investigate their correlation with disease activity. METHODS: The study included 48 rheumatoid arthritis patients and 42 age and sex matched healthy controls. Serum levels of IL-37 were determined using enzyme linked immunosorbent assay while percentage of CD3+CD26+T cells in peripheral blood mononuclear cells was assayed using flowcytometry. RESULTS: Serum levels of IL-37, as well as the percentage of CD3+CD26+T cells, were significantly higher in rheumatoid arthritis patients than in healthy controls. Also, serum IL-37 levels were higher in patients with severe disease activity than patients with moderate and low disease activity. In rheumatoid arthritis patients, both serum levels of IL-37 and percentage of CD3+CD26+T cells correlated with disease activity (DAS28), C-reactive protein levels and erythrocyte sedimentation rate. In addition, serum levels of the anti-inflammatory cytokine IL-37 positively correlated with the percentage of CD3+CD26+T cells in peripheral blood of rheumatoid arthritis patients. CONCLUSION: Our results indicate a strong correlation between serum levels of IL-37 and frequency of activated T cells in peripheral blood of rheumatoid arthritis patients. Our results suggest that in an active disease status, activated T lymphocytes may be a contributing source to the elevated levels of IL-37 trying to down-regulate the active inflammatory process.

Growth Differentiation Factor-15 (GDF-15) Level and Relation to Clinical Manifestations in Egyptian Systemic Sclerosis patients: Preliminary Data.

AIM OF THE WORK: This study aims to assess Growth differentiation factor-15 (GDF-15) level in Scleroderma patients and its relation to disease manifestations. PATIENTS AND METHODS: This study included 55 scleroderma patients and 40 age and sex matched healthy volunteers. All patients were subjected to full history taking, thorough clinical examination, and laboratory investigations. GDF-15 serum levels were analyzed in patients and controls using human GDF-15 immunoassay Quantikine ELISA kit. RESULTS: The GDF-15 serum level was significantly higher in Systemic sclerosis (SSc) patients in comparison to healthy control individuals, p-value = 0.004. In addition, the GDF-15 serum levels increased in a significant way in patients with diffuse SSc than those with limited SSc, p = 0.026. Also, we had discovered a significant positive correlation between serum GDF-15 levels and the modified Rodnan score of the SSc patients, r = 0.442, p = 0.001 and a significant association was found between high GDF-15 level and SSc patients with interstitial pulmonary fibrosis (IPF) as compared to healthy controls (p = 0.002). However, no significant difference was found between SSc patients without IPF and healthy subjects regarding GDF-15 level (p = 0.106). CONCLUSION: GDF-15 serum levels were elevated in patients with SSc and correlated with the extent of skin fibrosis, and it was found to be higher in SSc patients with IPF. Such results may suggest a pivotal role of GDF-15 in fibrotic changes in SSc, and GDF-15 could be a treatment target in SSc patients in future.