Background/Purpose: TNF-like weak inducer of apoptosis (TWEAK), a member of the tumor necrosis factor (TNF) family, has emerged as a cytokine that regulates multiple cellular responses, including proinflammatory activity, angiogenesis and cell proliferation. Increased levels of TWEAK were observed in many types of autoimmune diseases, such as rheumatoid arthritis, multiple sclerosis, and systemic lupus erythematosus. However, information about TWEAK in polymyositis and dermatomyositis is limited.The aim of the present study was to investigate the expression of TWEAK in patients with polymyositis and dermatomyositis.

Methods: Twenty four patients with polymyositis, twenty two dematomyositis patients and twenty four healthy controls were recruited in the study. Serum levels of TWEAK were measured by ELISA. TWEAK messenger RNA (mRNA) expression in skeletal muscle from 19 out of 46 PM/DM patients and 11 healthy controls was detected by relative quantification RT-PCR. The results of two groups were compared using unpaired t test.

Results: Serum levels of TWEAK in PM/DM patients were significantly higher compared to healthy controls [(555.34±124.05)pg/ml vs (346.22±146.29)pg/ml, P<0.05]. However, there was no statistically significant difference between PM patients and DM patients[(533.34±119.67)pg/ml vs (579.25±127.06)pg/ml,P>0.05]. TWEAK mRNA in skeletal muscle showed a higher level in skeletal muscle of PM/DM patients than healthy controls, using GAPDH gene as reference gene .

Conclusion: The present study shows that serum levels and mRNA expression of TWEAK were elevated in patients PM/DM. TWEAK may possibly be enrolled in pathogenesis of PM/DM.

ACR Meeting Abstracts - https://acrabstracts.org/abstract/elevated-level-of-tumor-necrosis-factor-like-weak-inducer-of-apoptosis-in-patients-with-polymyositis-or-dermatomyositis/