Oral, daily prednisone dose in nine patients treated with anakinra at initiation of therapy (time 0) and at last follow-up. p-value was obtained by paired Student's t test.

(a) Production of IL-1b by activated SoJIA PBMCs. PBMCs from SoJIA patients (n = 5) and healthy controls (n = 5) were activated with PMA/Ionomycin for 24 h. Release of IL-1b into the supernatants was assayed with Luminex. Production of IL-6 (b) and TNF (c) by the same activated SoJIA PBMCs. p-values were calculated by nonparametric (Mann-Whitney) tests.

Values of (a) temperature; (b) active joint count; (c) white blood cells (WBC); (d) hemoglobin; (e) platelet count; and (f) ESR in 9 SoJIA patients. Values on the x axis represent months before (−2) initiation of Anakinra treatment (0) and up to 2–12 mo of follow up (average, 6.6 mo). Arrows indicate the time of treatment initiation. p-values were calculated at time 0 and at 2-mo follow-up (paired, two-tailed t test). Color codes for individual patients (from Table I) are represented at the bottom.

(a) Effects of SoJIA sera on healthy PBMCs. Incubation of healthy PBMCs with autologous sera and sera from four patients who had active SoJIA (SYS33, SYS46, SYS53, and SYS27) induced up-regulation of 46 genes. The microarray data of healthy PBMCs that were incubated with patients' sera were normalized to the same PBMCs that were cultured with autologous serum. Probes that did not differ significantly between unincubated PBMCs and PBMCs that were cultured with autologous serum were selected. Of those, only gene probes whose expression was up-regulated more than twofold by at least two SoJIA sera were selected further. IL-6 did not fulfill this criterion but is shown for comparison. Median fold up-regulation by the four SoJIA sera incubation is depicted in the left column. Number of SoJIA sera that induced greater than twofold up-regulation is shown in the next column. (b) Expression of the gene probes selected in Fig. 1 a in the PBMCs of 16 active SoJIA patients. The patient's PBMCs expression data were normalized to the median expression of the same gene probes in the PBMCs of 12 healthy children. Median gene expression and number of samples with greater than twofold up-regulation are depicted in the first two columns. Third column represents the number of samples with a P (present) flag according to Affymetrix MAS 5.0 scaled gene expression data. Asterisks on the gene denominations mean that the expression of those genes is significantly different (Mann-Whitney < 0.05) in patients compared with controls. p-values are given next to these genes. (c) Induction of IL-1b protein secretion in healthy PBMCs incubated with SoJIA sera. Supernatants from 6 h incubation of healthy PBMCs with 12 SoJIA sera and 3 healthy controls were assayed for IL-1b production by Luminex. (d) Induction of IL-1b protein secretion in SoJIA patients who did and did not have systemic symptoms. IL-1b protein secretion is induced preferentially by sera from SoJIA patients who experience systemic symptoms (SoJIA1, n = 5) over those patients who only had active arthritis (SoJIA2, n = 7). All results were analyzed using nonparametric tests (Mann-Whitney).