Altered Ikappa B alpha expression promotes NF-kappaB activation in monocytes from primary Sjögren's syndrome patients

AIMS: 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. METHODS: 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). RESULTS: 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. CONCLUSIONS: 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.