Soluble urokinase plasminogen activator receptor suPAR as a marker for inflammation in pediatric inflammatory bowel disease.

OBJECTIVE: In inflammatory bowel disease (IBD), more means to monitor early therapeutic response are needed. In pediatric IBD, blood inflammatory markers erythrocyte sedimentation rate (ESR) or C-reactive protein (CRP) may be low in 10 to 20% of patients with severe disease. Recently, soluble urokinase plasminogen activator receptor (suPAR) was described as a potential blood inflammatory marker in adult IBD. METHODS: We tested the performance of suPAR by the start of therapy with glucocorticoids (n = 19) or TNF-α-antagonist (n = 16) in pediatric IBD (Crohn's disease n = 19, ulcerative colitis (UC) n = 16). RESULTS: The levels of suPAR were low in both patient groups studied. There was no difference in the values regarding the presence of Crohn's disease or ulcerative colitis. Thus, all analyses were performed on the entire sample set. Glucocorticoid therapy, however, resulted in a significant decline in suPAR levels from a median of 3.06 to 2.54 ng/ml (p < 0.01). In contrast, TNF-α-antagonist had no effect. The suPAR levels did not associate with ESR or CRP or fecal calprotectin (FC). CONCLUSIONS: In pediatric IBD, the suPAR levels in blood are low and do not reflect the level of intestinal inflammation assessed with FC. The introduction of corticoids, however, results in a decline of suPAR levels in blood but not reflect therapeutic response to TNF-α-antagonist. Thus, suPAR is of limited value in assessing systemic inflammatory responses in pediatric IBD.

Serum MMPs 7-9 and their inhibitors during glucocorticoid and anti-TNF-α therapy in pediatric inflammatory bowel disease.

OBJECTIVES: In inflammatory bowel diseases (IBD), matrix metalloproteinases (MMPs) participate in intestinal tissue damage and regenerative processes. MMP activity is inhibited by tissue inhibitors of MMPs (TIMPs) and plasma inhibitor, α2-macroglobulin (α2M). We evaluated serum MMPs, their inhibitors and markers of neutrophil activity, myeloperoxidase (MPO) and human neutrophil elastase (HNE), during glucocorticoid (GC) and anti-TNF-α therapies in pediatric IBD, in aim to find new tools for assessment of therapeutic response. METHODS: Serum samples were collected before and within a month after the start of therapy with oral GC (n = 19) or anti-TNF-α agent (n = 16), and from 32 pediatric control patients. Serum levels of MMP-7, MMP-9, TIMP-1, TIMP-2, α2M, MPO, and HNE were analyzed with enzyme-linked immunoabsorbent assays (ELISA) and MMP-8 by immunofluorometric assay (IFMA). Disease activity was monitored with erythrocyte sedimentation rate (ESR), CRP, fecal calprotectin (FC), and physician's global assessment of clinical disease activity (PGA). RESULTS: In IBD, pretreatment serum MMP-7, MMP-8, MMP-9, α2M, MPO, and HNE were elevated compared with controls. During GC therapy, MMP-7, TIMP-1, and MMP-7/TIMP-2 decreased (all p < 0.05). During anti-TNF-α therapy, MMP-7 decreased (p = 0.063), but remained higher than that after GC therapy (p < 0.05). α2M (p < 0.05) and HNE (p < 0.05) increased, the former higher than that in GC-treated patients. The levels of MMPs and their inhibitors did not markedly associate with inflammatory markers in blood or feces. CONCLUSIONS: In pediatric IBD, serum MMP-7 mirrors disease activity, and together with TIMP-1, reflects GC therapy response. α2-Macroglobulin expression parallels the anti-TNF-α response.

Serum immune-activation potency and response to anti-TNF-α therapy in Crohn's disease.

AIM: To study whether immune-activation stage in serum of adult Crohn's disease (CD) patients correlates with disease activity and with treatment response to anti-tumor necrosis factor-α (TNF-α) therapy. METHODS: Serum samples were obtained from 15 adult CD patients introduced to anti-TNF-α therapy. The individual stage of immune activation was studied applying our new in vitro assay, in which target cells (donor derived peripheral blood mononuclear cells) were cultured with patient serum and the T-cell activation induced by the patient serum was studied using a panel of markers for effector [interferon γ (IFNγ), interleukin (IL)-5] and regulatory T-cells [forkhead transcription factor 3 (FOXP3) and glucocorticoid-induced tumour necrosis factor receptor (GITR)]. The endoscopic disease activity was assessed with the Crohn's disease endoscopic index of severity (CDEIS) before and 3 mo after therapy with an anti-TNF-α agent. RESULTS: Low induction of FOXP3 and GITR in target cells cultured in the presence of patient serum was associated with high disease activity i.e. CDEIS assessed before therapy (r = -0.621, P = 0.013 and r = -0.625, P = 0.013, respectively). FOXP3 expression correlated inversely with pre-treatment erythrocyte sedimentation rate (r = -0.548, P = 0.034). Low serum induced FOXP3 (r = -0.600, P = 0.018) and GITR (r = -0.589, P = 0.021) expression and low IFNγ secretion from target cells (r = -0.538, P = 0.039) associated with treatment response detected as a decrease in CDEIS. CONCLUSION: The immune-activation potency in the patient serum prior to anti-TNF-α therapy reflected intestinal inflammation and the therapeutic response.

New means to monitor the effect of glucocorticoid therapy in children.

AIM: To study the individual effects of glucocorticoid (GC) therapy on the state of immune activation in patient serum. METHODS: We developed a novel assay in which the effect of corticosteroid-treated patient serum on healthy donor peripheral blood mononuclear cells (target cells) was studied, with a panel of markers for effector [interferon (IFN)gamma and interleukin (IL)-5] and regulatory T cells (FOXP3 and glucocorticoid-induced tumor necrosis factor receptor, GITR). The study group comprised 19 children with inflammatory bowel disease. The individual effect of patient serum on target cells was analyzed prior to GC therapy and 2 wk later. RESULTS: The effect of GC therapy mediated by patient serum was seen as a decrease in the target cells expression of regulatory T-cell-related markers GITR (median suppression 24%, range of suppression 1%-63%, in 2 cases increase of 6% and 77%, P < 0.01 for mitogen-activated target cells) and FOXP3 (median suppression 33%, range of suppression 0%-79%, in one case an increase of 173%, P < 0.05 for resting cells), and secretion of IFNgamma [from a mean of 87 700 pg/mL (SD 33 900 pg/mL) to 60 900 pg/mL (SD 44 200 pg/mL) in mitogen-activated target cells, 13 of the cases showed a decrease, P < 0.01]. The total or weight-related prednisolone dose did not correlate with the patient-serum-induced changes in the target cell markers. CONCLUSION: GC response could be monitored at an individual level by studying the effect of patient serum on signaling pathways of target immune cells.