Novel NLRP3/cryopyrin mutations and pro-inflammatory cytokine profiles in Behçet's syndrome patients

• Published in: International immunology Vol. 26; no. 2; pp. 71 - 81
• Main Authors: Yüksel, Şahru, Eren, Elif, Hatemi, Gülen, Sahillioğlu, Ali Can, Gültekin, Yetiş, Demiröz, Duygu, Akdiş, Cezmi, Fresko, İzzet, Özören, Nesrin
• Format: Journal Article
• Language: English
• Published: England 01.02.2014
• Subjects: Adult; Behcet Syndrome - genetics; Behcet Syndrome - immunology; CARD Signaling Adaptor Proteins; Carrier Proteins - genetics; Cells, Cultured; Cytoskeletal Proteins - genetics; DNA Mutational Analysis; Female; Genetic Predisposition to Disease; Humans; Inflammation Mediators - metabolism; Interleukin-1beta - metabolism; Lipopolysaccharides - immunology; Male; Mutation - genetics; NLR Family, Pyrin Domain-Containing 3 Protein; Polymorphism, Genetic; Tumor Necrosis Factor-alpha - metabolism; Turkey; Young Adult; autoinflammation; ASC; TNF-α; IL-1β; NLR
• ISSN: 0953-8178; 1460-2377
• DOI: 10.1093/intimm/dxt046

Behçet's syndrome (BS) is a systemic inflammatory disorder with unknown etiology. Features of both innate and adaptive immunity have been claimed in the pathogenesis of BS. To test the possible dysregulation of the NLRP3/cryopyrin (Nod-like receptor with a pyrin domain 3) inflammasome, as a result of mutation(s), we performed single-strand conformation polymorphism analyses and/or sequencing of all the coding regions and intron-exon boundaries of NLRP3/cryopyrin and ASC (apoptosis-associated speck-like protein containing CARD) genes from Turkish BS patients and healthy controls. At the same time, we determined pro-inflammatory cytokine secretion profiles of peripheral blood cells in response to LPS treatment using ELISA. BS patients with vascular involvement showed significantly increased levels of TNF-α release at 2-, 4- and 8-h post-treatment and significantly increased IL-1β levels were detected at 2h (P = 0.005) and 4h (P = 0.025) (n = 10). We identified four mutations in the NLRP3/cryopyrin gene, V200M (n = 3/104) and T195M (n = 1/104), in BS patients but none in control samples. No mutations were detected in the ASC gene. The effect of these NLRP3/cryopyrin mutants on ASC speck assembly and IL-1β secretion was tested and the V200M mutant was shown to induce IL-1β secretion. Thus, it is likely that certain mutations in NLRP3/cryopyrin in combination with yet unknown other factors may contribute to the pro-inflammatory cytokine profiles in BS patients.