To study the importance of IκBα in NF-κB signal transduction, we analysed the IκBα expression in monocytes from Sjögren's syndrome (SS) patients versus healthy controls.
Monocytes were obtained from the peripheral blood of 30 SS patients and 23 healthy subjects. IκBα expression was studied by semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR), real-time PCR, immunoblotting, flow cytometry and enzyme linked immunosorbent assay (ELISA).
Analysis of the gene and protein expression profiles of SS monocytes revealed a down-regulation of IκBα, and in all the Sjögren's syndrome cases examined, serum IκBα levels were significantly decreased in comparison with controls.
Our findings clearly demonstrate changes in the levels of IκBα in SS monocytes, suggesting that the attenuated expression of IκBα could contribute to the deregulation of NF-κB pathways in the SS pathogenesis. Decreased expression of IκBα may specifically amplify cytokines production and inflammatory response linked to Sjögren's syndrome.