Caspase-1 is active since the early phase of rheumatoid arthritis. (22nd February 2011)

• Record Type: Journal Article
• Authors: Cascão, Rita; Polido-Pereira, Joaquim; Canhão, Helena; Rodrigues, Ana Maria; Navalho, Márcio; Raquel, Helena; Mourão, Ana Filipa; Resende, Catarina; da Silva, José Alberto Pereira; Fonseca, João Eurico; Moita, Luis Ferreira
• Is Part Of: Annals of the rheumatic diseases. Volume 70(2011)Supplement 2
• Page Start: A2
• Page End: A2
• Publication Date: 2011-02-22
• Subjects: Rheumatism -- Periodicals; 616.723005
• DOI: 10.1136/ard.2010.149096.4
• Languages: English
• ISSNs: 0003-4967

Abstract

Abstract : Background: We have previously reported an increase in interleukin (IL)-1β levels in very recent onset arthritis. Therefore, molecular mechanisms that regulate IL-1β secretion, such as caspase-1 activation, might play a relevant role in arthritis onset and progression. Objectives: Our main goal was to evaluate caspase-1 state of activation in early polyarthritis and established rheumatoid arthritis (RA) patients. Materials and methods: Blood samples were collected from 12 untreated early polyarthritis patients, 12 established RA patients and 10 healthy controls. Caspase-1 activity was assessed using a carboxyfluorescein FLICA detection kit. Results: We found that both early polyarthritis and established RA patients have higher active caspase-1 levels. Surprisingly, caspase-1 activation levels in patient cells remain unchanged when cells were stimulated with Escherichia coli and ATP, whereas in control cells caspase-1 levels increased after stimulation. We observed no significant differences when comparing early polyarthritis with established RA samples. However, in RA patients with higher disease activity the proportion of active caspase-1 is higher. Conclusions: Our results suggest that leucocytes in both early polyarthritis and established RA patients have high baseline levels of activated caspase-1, which cannot be significantly increased after stimulation. Altogether, our data supports the hypothesis that caspase-1 is activated in early arthritis.