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Genetically Determined TNF-α Secretion Influences the Development of Dermatomyositis and Systemic Lupus Erythematosus
Lyubomir A Dourmishev1, Maria H Hristova2, Zornitsa G Kamenarska3
1Department of Dermatology and Venereology, Medical University of Sofia, Sofia, Bulgaria.
Background:
Abnormal secretion of TNF-α is known to play a role in the pathogenesis of dermatomyositis and systemic lupus erythematosus.
Materials And Methods:
In the present study we have analyzed the concentrations of TNF-α in the sera of 30 patients with systemic lupus erythematosus (SLE), 28 with dermatomyositis (DM) and 30 healthy controls by standard ELISA tests.
Results:
We have found that -308A allele increases TNF-α secretion, while -1031C and -863A alleles decrease it. The -857C/T and 489G/A polymorphisms appeared in strong linkage disequilibrium (D'=0.93) but they did not seem to affect TNF-α secretion.
Conclusion:
TNF-α polymorphisms play a significant role in its secretion and influence the development of DM and SLE.
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