PW01-008 – The inflammasome and secretory pathways in FMF

Methods 6 turkish patients with the clinical diagnosis of FMF exhibiting homocygous or combined heterozygous mutations within the MEFV gene were included. Patients still exhibited clinical symptoms and elevated inflammation markers despite sufficient colchicine therapy (“instable disease”). Healthy probands served as controls. Their health status was assessed by a standardized questionnaire. All patients and controls gave written consent. 25 – 30 ml blood was drawn and PBMC and granulocytes separated by a two density gradient centrifugation. 5 x 106 cells were stimulated with (i) mock, (ii) PMA (10nM), (iii) LPS (10ng/ml) and (iv) LPS (10ng/ml) + ATP (1mM) (later substance for the last 30 minutes). In a similar approach cells were treated with additional colchicine (5μg/ml) for the whole incubation time. Supernatant was gained and frozen at -20oC after 5 hours. ELISA for S100A12, IL-18 and caspase-1 were performed according to standard protocols. At the time of blood drawing high sensitivity CRP was measured. Results Compared to controls even unstimulated granuloytes from FMF patients with instable disease secreted significantly more S100A12 (mean controls 43ng/ml vs. mean patients 327ng/ml, p <.01), IL-18 (0pg/ml vs. 274pg/ml, p <.01) and caspase-1 (10pg/ml vs. 81pg/ml, p <.01). Stimulation also induced enhanced secretion of S100A12 (PMA: 61ng/ml vs. 336ng/ml, p <.01; LPS: 74ng/ml vs. 247ng/ml, p <.01; LPS/ATP: 94ng/ml vs. 252ng/ml, p <.01), IL-18 (LPS: 3,6pg/ml vs 176pg/ml, p <.05; LPS/ATP: 7pg/ml vs. 198pg/ml, p <.05) and caspase-1 (LPS: 23pg/ml vs. 72pg/ml, p <.01; LPS/ATP: 32pg/ml vs. 69pg/ml, p <.05). Furthermore, supplementary colchicine significantly suppressed the hypersecretion of S100A12, IL-18 and caspase-1.