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Interleukin-10 (IL-10) deficiency in gene knockout mice causes chronic enterocolitis. We hypothesized that inflammation in human inflammatory bowel disease might result from innate alterations in the IL-10 pathway. Serum, supernatants, and mRNA of peripheral blood mononuclear cells (PBMC) and lamina propria mononuclear cells (LPMC) derived from inflamed (LPMC-i) and noninflamed colonic mucosa (LPMC-ni) were collected from patients with Crohn's colitis, ulcerative colitis, and controls. IL-10 protein concentrations and IL-10 mRNA were examined in response to PMA/CD3 or PHA stimulation. The response to rhIL-10 was assessed by inhibition of tumor necrosis factor-alpha (TNF-α), IL-6, and interferon-gamma (IFN-γ) production. Serum IL-10 levels of inflammatory bowel disease (IBD) patients were within the normal range. IL-10 concentrations in supernatants from LPMC-i were significantly lower than from LPMC-ni or PBMC. No difference was seen between samples from ulcerative colitis and Crohn's disease. IL-10 mRNA was detected in 0/4 LPMC-i samples compared to 1/6 LPMC-ni and 6/6 PBMC. RhIL-10 inhibited TNF-α, IL-6, and IFN-γ synthesis in PBMC. This effect was strongly diminished in LPMC. Disease-specific alterations were not detected. Our data suggest that LPMC derived from inflamed colonic mucosa have a reduced ability to produce and to respond to rhIL-10. A disease-specific alteration in the IL-10 pathway, however, was not found.

To investigate the clinical relevance of interleukin-6 (IL-6) serum levels in patients with Crohn's disease (CD), single point IL-6 measurements in sera from consecutive CD patients and healthy donors (HD), as well as longitudinal measurements during the course of steroid therapy for active CD were performed. Patients with steroid-induced remission were followed until clinical relapse.One hundred thirty-six CD patients without steroid or other immunosuppressive treatment within 2 months and surgical procedures within 3 months before study entry were investigated; 63 patients with active CD were enrolled into the follow-up program. Clinical activity was evaluated by the Crohn's disease activity index (CDAI) and serum IL-6 levels measured by enzyme-linked immunosorbent assay.IL-6 serum levels were significantly elevated in CD patients compared to HD (p0.001). In individual patients serum IL-6 levels correlated with corresponding CDAI scores in a subgroup referred to as primarily inflammatory patients presenting without bowel stenosis, previous intestinal resection, or concomitant inflammatory disorders (r = 0.72, p0.001). Primarily inflammatory patients displayed higher serum IL-6 levels (median: 6.0 pg/ml; range: 1.3-25) than CD patients with bowel stenosis (median: 2.0; range: 1.3-4.9; p0.01) or extensive intestinal resection (median: 1.5; range: 1.3-13.7; p0.001). Longitudinally measured serum IL-6 levels reflected the clinical response during steroid therapy and predicted clinical relapse after steroid-induced remission at week 9 of the treatment protocol.Serum IL-6 is a clinically relevant parameter for CD that correlates with inflammatory activity and implies a prognostic value after steroid-induced remission.

Intestinal blood loss as well as chronic inflammation are regarded as the most important mechanisms in the pathogenesis of anemia in Crohn's disease. In addition, cytokines such as interleukin-6 can suppress erythropoietin production. This study was performed to investigate the importance of iron status, inflammatory activity, and endogenous erythropoietin concentrations for the development of anemia in Crohn's disease. In 49 consecutive patients with Crohn's disease, hemoglobin, inflammatory activity (Crohn's disease activity index, C-reactive protein, alpha 1-acid glycoprotein), iron status (serum iron, transferrin, transferrin saturation, ferritin), and serum erythropoietin levels were studied. Anemic (Hb12.0 g/dl; N = 16) vs nonanemic patients (Hbor = 12 g/dl; N = 33) showed reduced iron compartments (eg, ferritin 28.7 +/- 12.9 micrograms/liter vs 63.2 +/- 15.0 micrograms/liter, transferrin saturation 6.2 +/- 1.4% vs 11.5 +/- 1.3%, P0.01) but no differences in inflammatory activity. An inverse correlation between erythropoietin and hemoglobin concentrations was found (r = -0.62; P0.001), but the increase in erythropoietin levels was inadequate to the degree of anemia. There was no correlation between erythropoietin and interleukin-6 serum levels. Four of five anemic patients with hemoglobin below 10.5 g/dl and erythropoietin levels within the normal range were treated with parenteral iron (200 mg iron saccharate in 250 ml NaCl, weekly, intravenously). Two of them additionally received recombinant human erythropoietin (150 units/kg, 3x weekly, subcutaneously). After five weeks all patients had a marked increase in hemoglobin. However, the mean increase in erythropoietin-treated patients was 5.0 g/dl compared to 2.0 g/dl in the patients with iron therapy only.(ABSTRACT TRUNCATED AT 250 WORDS)

Uridine diphosphate glucuronosyltransferase (UGT) was identified as an antigenic target in a subgroup of liver-kidney microsomal autoantibodies and was termed LKM-3. To evaluate the nature of LKM-3 antibodies, we screened sera from 80 untreated patients with autoimmune hepatitis (AIH) type 1 and 2, primary biliary cirrhosis (PBC), AIH/PBC, hepatitis C virus (HCV) infection, and 12 healthy individuals (controls) against 7 recombinant human UGT isoenzymes (UGT1A1, UGT1A4, UGT1A6, UGT1A7, UGT1A9, UGT1A10, and UGT2B7). Autoantibodies reacting against various UGT isoenzymes were observed in sera from 3 of 18 AIH type 2 and 1 of 27 of the HCV patients. The anti-UGT-positive sera from AIH type 2 patients revealed the strongest immunoreactivity against UGT1A1, the main UGT-isoform involved in the bilirubin glucuronidation. Additionally, these sera were able to block UGT-mediated substrate glucuronidation in vitro. The prevalence for UGT1A1 was shown by 2 independent techniques: (1) UGT1A1 was identified as the main antigen by Western blotting. Preabsorption of sera with UGT1A1 prevented reaction against all tested UGT-isoforms. (2) In vitro immunoinhibition experiments showed that glucuronidation of the anticancer drug flavopiridol by UGT1A1 was more strongly inhibited than its UGT1A9-mediated biotransformation. In contrast, the serum from the HCV-patient reacted predominately with UGT1A6, and moreover, the immunoreactivity pattern was different from that of the AIH group. To summarize, we show the subtype preference of antibodies against UGT1A1 in a subgroup of AIH type 2 patients. These autoantibodies inhibit UGT-mediated glucuronidation in vitro, but it is unlikely that anti-UGT antibodies will have a marked effect on the patients capacity for drug biotransformation, as serum bilirubin levels in patients remained within the normal range.

Objective: Budesonide, although only topically active, is effective in the treatment of Crohn’s disease. This study was performed to compare the clinical efficacies of budesonide and prednisolone in relation to the activation status of circulating leukocytes. Methods: Twenty-four patients with active Crohn’s disease were randomized to treatment with either budesonide or 6-methylprednisolone. Clinical response was monitored by the Crohn’s disease activity index, C-reactive protein, and orosomucoid. Expression of CD25 and CD71 on T cells and CD64 on neutrophils was determined by flow cytometry. The release of TNF-α and IL-1β by peripheral blood mononuclear cells was measured by ELISA. Results: After 2 wk of treatment a clinical response was observed in both groups, but it was more accentuated in patients treated with prednisolone. At baseline an upregulation of CD71 and CD64, but not CD25, was found in active patients. Prednisolone significantly decreased the expression of CD64 and the release of TNF-α and IL-1β, but did not alter the expression of CD25 and CD71. Budesonide treatment failed to exert any effect on circulating leukocytes. Conclusions: The inability of budesonide to downregulate activated circulating leukocytes may contribute to the somewhat lower clinical efficacy of this topical steroid in the treatment of active Crohn’s disease.

Peripheral blood mononuclear cells (PBMC) from 40 patients with gastrointestinal carcinoma (GIC), 13 patients with primary carcinoma in other localizations(non-GIC), and from 57 apparently healthy donors were isolated by Ficoll-Paque gradient centrifugation. The separated cells were stained with several monoclonal antibodies and subjected to analysis on a fluorescence-activated cell sorter. A decreased percentage of PBMC expressing T cell antigens was noted amongst GIC patients, and was mainly due to a reduction of the Leu 2a subset, thus, leading to an increase in the Leu 3a/Leu 2a ratio from 1.4 to 2.1 Non-GIC patients had decreased numbers of both T helper and suppressor cells. Amongst PBMC from GIC and non-GIC patients a statistically increased percentage of cells expressed LeuM 2 (P less than 0.001), LeuM 3 (P less than 0.001), OKM 1 (P less than 0.005), VEP 9 (P less than 0.001), and HLA-DR (P less than 0.001) antigens compared to healthy controls. The percentage of cells bearing these monocyte/macrophage antigens correlated well with the number of cells having monocyte morphology, stained for non-specific esterase, phagocytosed latex particles, and expressed Fc IgG receptor. Our results demonstrate clearly that tumor-bearing patients have an increased relative number of monocytes. The data suggest that cells of the macrophage lineage may be involved in defense mechanisms and changes of the immune system evoked by various tumors.