Autoimmune diseases in gastroenterology

There are several different diseases in gastroenterology with an important role of immunological mechanisms in their pathogenesis. We know autoimmune diseases with immunological reactions against liver or pancreatic tissue. In addition there are diseases like chronic inflammatory bowel diseases representing inappropriate immunological reactions followed by inflammation and tissue destruction. The research of the last decade has contributed significantly to the understanding of the pathogenesis of diseases based on immunological mechanisms and consequently to the development of novel therapeutic strategies targeting molecules. Chronic inflammatory bowel diseases, autoimmune hepatitis, primary sclerosing cholangitis, primary biliary cirrhosis, autoimmune pancreatitis, and celiac disease are the most important diseases with immunological pathogenesis in Gastroenterology. Especially in chronic inflammatory bowel diseases ulcerative colitis and Crohn's disease with immunosuppressive drugs and monoclonal antibodies new preparations are used in therapy. Autoimmune pancreatitis was characterized as an own entity in the last years. Therefore, this review will focus on these diseases.

Short-term efficacy of tacrolimus in steroid-refractory ulcerative colitis - experience in 130 patients

BACKGROUND

Steroid-refractory ulcerative colitis (UC) remains a challenging condition warranting surgery upon failure of pharmacological treatment. Calcineurin inhibitors or infliximab are alternatives in this situation. Data on the efficacy and safety of tacrolimus in this setting are limited.

AIM

To study the short-term efficacy and safety of tacrolimus in moderate-to-severe steroid-refractory UC. The role of thiopurines in this situation and predictors of colectomy were evaluated.

METHODS

In three centers, all charts from tacrolimus-treated patients with steroid-refractory UC were reviewed. Efficacy was assessed by colectomy-free survival and clinical remission at 3 months.

RESULTS

We identified 130 patients with pancolitis in 75 (59%), left-sided disease in 35 (27%) and proctitis in 18 patients (14%) (disease localisation not obtainable in two patients). The median age was 40 (range: 18-81). Clinical activity according to the median Lichtiger score decreased from 13 (range: 4-17) at baseline to 3 (0-14) at week 12. Eighteen patients underwent colectomy within the first 3 months of treatment with tacrolimus (14%). Clinical remission was achieved in 94 patients (72%) in this period. Thiopurines given in parallel to tacrolimus tended to limit colectomy and significantly increased remission (P = 0.002) in the short-term. No other predictors of colectomy or remission were identified. Side effects were noticed in 53% of patients and no severe events occurred.

CONCLUSION

This large survey confirms the efficacy and safety of tacrolimus in patients with steroid-refractory ulcerative colitis.

Prophylactic application of bovine colostrum ameliorates murine colitis via induction of immunoregulatory cells

Epidemiologic studies suggest a relationship between early weaning and the incidence of inflammatory bowel disease. Herein, we addressed the question whether bovine colostrum, the first milk produced by mammals, is able to prevent dextran sulfate sodium (DSS)-induced colitis in mice. Prior to induction of colitis with 5% DSS, Naval Medical Research Institute mice were fed bovine colostrum [BV-20 or 200 mg/kg body weight (BW)], BSA (20 mg/kg BW), or water (100 μL) daily by oral gavage for 2 wk. The clinical severity of colitis was determined by scoring changes in BW and colon length reduction. Following 2 wk of observation, the colons were removed for histologic and immunohistochemical evaluation of inflammation. Flow cytometric phenotyping of leukocyte subsets was performed from peripheral blood, mesenteric lymph nodes, and spleens. Administration of bovine colostrum improved the clinical and histologic severity of colorectal inflammation. Compared with BSA-fed and water-fed controls, BV-20 pretreated mice had significantly less severe weight loss and decreased colon shortening. Beneficial effects were accompanied by redistribution of immunoregulatory, peripheral and splenic γδ TCR(+) cells, and CD11b(+)Gr1(+) cells. Higher colostrum doses did not affect disease activity. In summary, prophylactic administration of colostrum improved clinical symptoms of colorectal inflammation in a well-established mouse model of DSS-induced colitis. Further investigations will target the underlying immunomodulatory mechanisms to our approach.

Schistosoma mansoni infection but not egg antigen promotes recovery from colitis in outbred NMRI mice

BACKGROUND

The ability of intestinal helminths to manipulate the immune system of their host towards a Th2 response has been proposed to modulate auto-immune and allergic diseases.

AIMS

This initial study investigated the anti-inflammatory potential of S. mansoni and soluble egg antigen (SEA) in a murine model of colitis.

METHODS

Colitis was induced in female NMRI mice by 5% dextran sulfate sodium (DSS) for 7 days, either 9 weeks post-infection with S. mansoni or during treatment with SEA. In addition to clinical signs of colitis, colon histology, immunohistochemistry, and flow cytometry of leukocytes were performed. Colon cytokines were measured using a quantitative real-time technique.

RESULTS

Infection with cercariae of S. mansoni attenuated DSS-induced colitis. Clinical symptoms such as weight loss and shortening of colon length were significantly prevented. Histological scores and cell infiltration were affected and expression of pro-inflammatory cytokines in the colons of infected DSS colitis mice was reduced. In contrast, application of SEA failed to improve colitis, even though some findings like earlier manifestation of inflammation and local induction of Th2 cytokines were similar to the effects of cercarial infection.

CONCLUSIONS

The results presented here suggest that SEA treatment could not protect mice from acute colitis. However, both infection with S. mansoni and injection of SEA affect mucosal immune responses.

Inflammation and immunity in the tumor environment

The relationship between inflammation, innate immunity and cancer is widely accepted. Cancer-associated inflammation includes infiltrating leukocytes, cytokines, chemokines, growth factors, lipid messengers and matrix-degrading enzymes. Tumor-associated macrophages and lymphocyte subpopulations are major components of the leukocyte infiltrate in most tumors. However, the cytokine and chemokine expression profile of the tumor microenvironment may be more relevant than its specific immune cell content. Apart from inflammatory cells, tumor stroma consists of new blood vessels and connective tissue. Many factors produced by tumor cells promote tumor angiogenesis and generation of extracellular matrix. Investigations regarding the link between inflammation and cancer are vital for identifying cell or protein targets for cancer prevention and therapy. Based on the relation between inflammation and cancer, different forms of immunotherapy have been developed. In a mouse model, we investigated the potential of Streptococcus pyogenes to achieve a bacteria-related immune response against tumor cells followed by tumor regression. As a model of pancreatic carcinoma, the aggressively growing and poorly immunogenic Panc02 tumor model was chosen. Our findings showed that a local application of bacteria mediates complete tumor regression. Future investigations should focus on the optimization of immunotherapeutic approaches that incorporate live bacteria or bacterial components.

Reduction of dendritic cells by granulocyte and monocyte adsorption apheresis in patients with ulcerative colitis

The influence of the granulocyte/monocyte apheresis (GMCAP) on cell populations participating in mechanisms of tolerance, e.g. dendritic cells (DCs), is still not very clear. In a first step, we aimed to investigate changes in the DC population of patients suffering from ulcerative colitis (UC) (n = 13) compared to healthy subjects (n = 9). In a second step, we studied the changes in peripheral DCs in a small group of patients with active UC before and after Adacolumn apheresis (n = 7). For this purpose, plasmacytoid and myeloid DCs and their maturation markers CD40, CD80, and CD86 were measured using four-color flow cytometry in the peripheral blood. After apheresis, and in acute flare-ups, we identified a significantly lower number of lymphocytes, plasmacytoid, and myeloid DCs. In conclusion, the additional removal of peripheral DCs by GMCAP, which otherwise would contribute to the inflammatory process in the gut, may lead to a higher tolerogeneic status towards luminal antigens.

Pancreatic cancer regression by intratumoural injection of live Streptococcus pyogenes in a syngeneic mouse model

BACKGROUND

This study addressed the potential of bacteriolytic therapy using Streptococcus pyogenes in a syngeneic pancreatic carcinoma mouse model.

METHODS

Panc02 tumours were either infected with S pyogenes or were treated with the equivalent volume of vehicle. In addition to assessment of tumour histology and immunohistochemistry, isolated splenocytes were analysed by flow cytometry. Interferon (IFN) gamma secretion as a reaction of splenocytes against tumour cells was shown through the ELISpot technique. A cytotoxic effect of lymphocytes against tumour targets was detected by lactate dehydrogenase (LDH) release. Cytokine levels in serum were measured.

RESULTS

A single application of live bacteria into established Panc02 tumours resulted in complete tumour regression. This antitumoral effect was accompanied by massive leucocyte infiltration into the tumours as well as a significant and sustained elevation of systemic levels of the proinflammatory cytokines IFN gamma, tumour necrosis factor alpha and interleukin 6. Lymphocytes obtained from treated mice specifically recognised syngeneic tumour cells in IFN gamma-ELISpot, and most importantly in cellular cytotoxicity assays, indicating a tumour-specific immune response.

CONCLUSIONS

We provide data that both the direct lytic activity of S pyogenes towards tumour cells and the infection-driven infiltration of tumours by cells of the innate immune system lead to damage of tumour cells followed by a dissemination of tumour components. This last outcome allows for the activation of tumour-specific effector cells, most probably in draining lymph nodes, promoted by the proinflammatory context. Taken together, these data indicate that the application of live S pyogenes may be a promising new treatment strategy for advanced pancreatic cancer patients that warrants further investigation.

Randomized, double blind controlled trial of subcutaneous recombinant human interleukin-11 versus prednisolone in active Crohn's disease

BACKGROUND

Interleukin-11 has shown benefit in animal inflammatory bowel disease models. Recently, recombinant human interleukin-11 (rhIL-11) has been observed to induce remission in a subset of patients with mild to moderate Crohn's disease (CD). The present study compared the efficacy of rhIL-11 versus prednisolone in remission induction in CD.

METHODS

Patients with active CD were randomly assigned to receive either subcutaneous rhIL-11 (1 mg once weekly) and prednisolone placebo tablets, or active prednisolone (60 mg/day) and rhIL-11 placebo, for 12 weeks. Prednisolone/placebo was tapered after week 1, and patients were assessed every second week.

RESULTS

Fifty-one patients received medication: 13/27 (rhIL-11) and 17/24 (prednisolone) completed 12 weeks of treatment. Remission rates (intent to treat) for rhIL-11 versus prednisolone were 4% versus 46% at week 4 (p < 0.001) and 19% versus 50% at week 6 (p < 0.05). Response to treatment (deltaCDAI > 100) was seen in 19% (rhIL-11) versus 63% (prednisolone) after 4 weeks (p < 0.002) and 37% versus 63% after 6 weeks (p = 0.1). After 12 weeks of treatment, it was observed that 22% (rhIL-11) versus 21% (prednisolone) had remained in remission. Frequent side effects of rhIL-11 included fever (n = 3), rash (4), arthralgia/arthritis (3), nausea/vomiting (3), and headache (6).

CONCLUSION

rhIL-11 is well tolerated but significantly inferior when compared to prednisolone in short-term remission induction in patients with active CD. In this patient cohort, both treatments appeared to be poor in maintaining remission over a period of 3 months.

Cis-hydroxyproline-induced inhibition of pancreatic cancer cell growth is mediated by endoplasmic reticulum stress

AIM: To investigate the biological effects of cis-hydroxyproline (CHP) on the rat pancreatic carcinoma cell line DSL6A, and to examine the underlying molecular mechanisms.

METHODS: The effect of CHP on DSL6A cell proliferation was assessed by using BrdU incorporation. The expression of focal adhesion kinase (FAK) was characterized by Western blotting and immunofluorescence. Induction of endoplasmic reticulum (ER) stress was investigated by using RT-PCR and Western blotting for the glucose-related protein-78 (GRP78) and growth arrest and DNA inducible gene (GADD153). Cell viability was determined through measuring the metabolic activity based on the reduction potential of DSL6A cells. Apoptosis was analyzed by detection of caspase-3 activation and cleavage of poly(ADP-ribose) polymerase (PARP) as well as DNA laddering.

RESULTS: In addition to inhibition of proliferation, incubation with CHP induced proteolytic cleavage of FAK and a delocalisation of the enzyme from focal adhesions, followed by a loss of cell adherence. Simultaneously, we could show an increased expression of GRP78 and GADD153, indicating a CHP-mediated activation of the ER stress cascade in the DSL6A cell line. Prolonged incubation of DSL6A cells with CHP finally resulted in apoptotic cell death. Beside L-proline, the inhibition of intracellular proteolysis by addition of a broad spectrum protease inhibitor could abolish the effects of CHP on cellular functions and the molecular processes. In contrast, impeding the activity of apoptosis-executing caspases had no influence on CHP-mediated cell damage.

CONCLUSION: Our data suggest that the initiation of ER stress machinery by CHP leads to an activation of intracellular proteolytic processes, including caspase-independent FAK degradation, resulting in damaging pancreatic carcinoma cells.

Prophylaktische Splenektomie während Resektion bei chronischer Pankreatitis

AIM

Chronic pancreatitis (CP) is the leading cause of splenic vein thrombosis (SVT). SVT occurs in about 15 % of patients with CP. The risk of variceal bleeding in SVT is approximately 10 %. Splenectomy is indicated in symptomatic SVT but its role in asymptomatic SVT is discussed controversially. Aim of our study was to evaluate the outcome of splenectomy performed during pancreatic resection in patients with CP and asymptomatic SVT.

METHODS

33 of 198 patients undergoing resection for CP underwent concomitant prophylactic splenectomy for asymptomatic SVT. Perioperative data were compared in the groups of patients with or without splenectomy. Follow-up was complete in 84 % (average 31 months).

RESULTS

Median operative time, postoperative morbidity, reoperation rate and mortality were not different in patients with or without splenectomy. The median number of blood units transfused was higher in patients with prophylactic splenectomy (6 vs 4 units; p < 0.01). One complication of splenectomy (postoperative bleeding) occurred (3 %). During follow-up no variceal bleeding, no episode of postsplenectomy sepsis or thrombosis due to temporary thrombocytosis occurred.

CONCLUSIONS

Complications of prophylactic splenectomy are rare and less frequent than reported episodes of variceal bleeding. In the presence of asymptomatic SVT splenectomy should be considered during pancreatic resection to facilitate surgery and to avoid further variceal bleeding.

Immunologic characterization of acute pancreatitis in rats induced by dibutyltin dichloride (DBTC)

There is little information available regarding the role of inflammatory cells and cytokines in the pancreatic tissue during acute interstitial pancreatitis. The single intravenous application of dibutyltin dichloride (DBTC) induces a pancreatitis in rats with a dosage dependent course. We analyzed the infiltrating leukocytes and the cytokine expression profile in the experimental model of DBTC-initiated mild interstitial pancreatitis during a time course of 4 weeks. Macrophages dominated among the infiltrating inflammatory cells detected by immunohistochemistry. The expression of IL-1beta, IL-10, and TGFbeta1 was shown to be elevated 24 hours after onset of pancreatitis reaching a maximum during the first week. Positive immunostaining of IL-1beta, IL-10, or TGFbeta1 was not restricted to infiltrating leukocytes but was found to various degrees in pancreatic cells. Transcripts of collagen type 1 reached high levels in the first week, but were down regulated thereafter. There was no significant expression of IL-2, IL-2 receptor, IL-4, TNFalpha, or IFNgamma. Our data show that the experimental interstitial pancreatitis was characterized by macrophage infiltration accompanied by elevated cytokine expression that lasted longer than the visible morphologic lesions. These inflammatory processes might create the environment that makes the pancreas more susceptible to further damaging effects.

Screening for p53 and K-ras mutations in whole-gut lavage in chronic inflammatory bowel disease

OBJECTIVES

Molecular screening for frequently mutated genes may increase the likelihood of identifying cancer risk groups, such as patients with longstanding inflammatory bowel disease. This study investigated the prevalence and time course of p53 and K-ras mutations in colonic lavage fluid of patients with inflammatory bowel disease.

METHODS

Colonic lavage fluid from 190 patients with ulcerative colitis (73), Crohn's disease (58) or controls (49 non-tumour, 10 colorectal cancer) was studied by oligomer-specific hybridization for K-ras mutations and single-strand conformation polymorphism (SSCP) for p53 mutations. Follow-up investigations were carried out after 1-3 years.

RESULTS

Mutations were most frequent in carcinomas (5/10, 50%) and rare in non-tumour controls (1/49, 2.0%). They were found in Crohn's colitis in 15.4%, in extensive ulcerative colitis in 18.6%, in left-sided ulcerative colitis in 13.3%, and in distal ulcerative colitis in 6.7% (P > 0.05). There was a positive association with disease duration (> or =11 years, P < 0.05). Follow-up investigations detected the same mutation in four patients and revealed new mutations in three patients.

CONCLUSIONS

In our large series of patients with inflammatory bowel disease, K-ras and p53 mutations could be detected with reasonable frequency and confirmed at follow-up in at least some patients. Our data encourage the use of molecular screening for the detection of malignant precursor lesions in at-risk patients.

Extracellular signal regulated kinases are key mediators of mitogenic signals in rat pancreatic stellate cells

BACKGROUND

Pancreatic stellate cells (PSCs) have been implicated in pancreatic fibrosis as they synthesise increased amounts of extracellular matrix proteins in response to activation by profibrogenic mediators such as cytokines.

AIMS

The purpose of this study was to analyse cytokine receptor stimulated signalling pathways involved in PSC activation. Using a rat culture model of PSCs, we have also tested the potential of the platelet derived growth factor (PDGF) antagonist trapidil and PD98059, a specific inhibitor of extracellular signal regulated kinase (ERK) activation, to suppress PSC growth.

METHODS

Cultured PSCs were stimulated with PDGF, and the signal transduction pathways activated in response to the mitogen were analysed by immunoblotting, kinase assays, and electrophoretic mobility shift assays. Furthermore, comparison of signalling cascades activated in PSCs before and after completing transdifferentiation to alpha-smooth muscle actin expressing myofibroblasts was performed. Biological effects of PDGF, trapidil, and PD98059 were analysed by proliferation assays and correlated with molecular effects of the substances.

RESULTS

PDGF induced rapid activation of Raf-1, ERKs 1 and 2, as well as AP-1 proteins. The transforming growth factor beta activated transcription factor Smad2 was found to be constitutively phosphorylated in PSCs of different transdifferentiation grades. Furthermore, the results indicate a correlation between ERK activities and induction of PSC activation. Trapidil efficiently inhibited both PDGF induced ERK activation and, in common with PD98059, PSC proliferation.

CONCLUSIONS

Our data suggest that ERKs play a key role in the regulation of PSC growth and that inhibition of the ERK signalling pathway may become a strategy to prevent activation of these cells.

Estradiol has a direct impact on the exocrine pancreas as demonstrated by enzyme and vigilin expression

BACKGROUND

Estrogen receptors have been found in the exocrine pancreas; however, the exact role of estrogen in pancreatic enzyme synthesis and secretion remains to be elucidated. Vigilin, a multi-KH domain protein, is part of a tRNA-containing ribonucleoprotein complex and may be a suitable marker for stimulation of the translational machinery. In the present study, we investigated the influence of estradiol and compared it to CCK on the expression of vigilin, trypsin and amylase in rat pancreatic acini.

METHODS

Acini were isolated and incubated with CCK or estradiol. The change in amylase and trypsin levels in the medium and in cell extracts were determined using a photometric method. The change in vigilin mRNA and protein expression were determined by RT-PCR and Western blotting, respectively.

RESULTS

Treatment of isolated exocrine pancreatic cells with estradiol caused stimulation of amylase and trypsin production and inhibition of secretion, while treatment with CCK showed only a minor effect on enzyme production and resulted mainly in a stimulation of secretion. Further we found an increase in vigilin mRNA and protein expression in acini stimulated with both CCK-8 and estradiol.

CONCLUSION

Our data suggest that estradiol may play a role in inducing exocrine enzyme production but not secretion, and that vigilin, as a marker for translational activity, is stimulated in parallel to the pancreatic enzymes: amylase and trypsin.

Expression of hepatocyte growth factor, keratinocyte growth factor and their receptors in experimental chronic pancreatitis

BACKGROUND

Hepatocyte (HGF) and Keratinocyte growth factors (KGF) are key factors of tissue organization and regeneration. These peptide growth factors and their receptors c-met and keratinocyte growth factor receptor (KGFR) are overexpressed in pancreatic cancer.

AIM

Expression and localization of ligands and receptors were investigated during the development of experimental chronic pancreatitis.

METHODS

Chronic pancreatitis was induced in rats by intravenous injection of dibutyltin dichloride. One to 60 days after treatment, the expression of growth factors and receptors was analysed by competitive polymerase chain reaction, Western blot analysis and immunohistochemistry.

RESULTS

HGF mRNA expression increased (10-fold) until days 7-14 followed by a decrease to control level. Expression of c-met mRNA constantly increased (15-fold). KGF and KGFR mRNA expression were increased after 14-28 days (5-fold) and then returned to control levels. mRNA expression patterns correlated with changes in the protein expression, whereas protein levels of KGF remained unchanged. Ligands were localized in mesenchymal cells and their receptors on epithelial cells.

CONCLUSIONS

The significant increase of HGF and c-met expression suggests an essential role of this growth factor in the morphological changes during the development of chronic pancreatitis. Changes in the expression of KGF and KGFR are less pronounced.

Cytokine mRNA levels and lymphocyte infiltration in pancreatic tissue during experimental chronic pancreatitis induced by dibutyltin dichloride

There is little information available regarding the role of inflammatory cells in the pathogenesis of chronic pancreatitis. Therefore, we analyzed the local cytokine profile and infiltrating lymphocytes in a rat model of chronic pancreatitis. Experimental pancreatitis was induced by a single intravenous application of dibultyltin dichloride (DBTC). During a time course of two months we observed the mRNA expression of cytokines using competitive RT-PCR. Lymphocytes were characterized by immunohistochemistry, FACS analysis, and the lymphocyte proliferation test. IL-1beta, IL-6, IL-5, and IL-10 were immediately up-regulated in the acute phase of disease, while lymphocyte-restricted expression of IL-2, IL-2R, and IFN-y was only found in the chronic course. Among the infiltrating lymphocytes, CD4+ cells dominated, but during the chronic process there was an increase of CD8+ cells, resulting in a reduced CD4/CD8 ratio. Mitogen-induced activation of isolated mesenteric lymph node cells increased during the chronic inflammation. Our results suggest that in experimental pancreatitis acute inflammatory reactions are followed by a T-lymphocyte-mediated process.

Cytokine mRNA levels and lymphocyte infiltration in pancreatic tissue during experimental chronic pancreatitis induced by dibutyltin dichloride

There is little information available regarding the role of inflammatory cells in the pathogenesis of chronic pancreatitis. Therefore, we analyzed the local cytokine profile and infiltrating lymphocytes in a rat model of chronic pancreatitis. Experimental pancreatitis was induced by a single intravenous application of dibultyltin dichloride (DBTC). During a time course of two months we observed the mRNA expression of cytokines using competitive RT-PCR. Lymphocytes were characterized by immunohistochemistry, FACS analysis, and the lymphocyte proliferation test. IL-1beta, IL-6, IL-5, and IL-10 were immediately up-regulated in the acute phase of disease, while lymphocyte-restricted expression of IL-2, IL-2R, and IFN-y was only found in the chronic course. Among the infiltrating lymphocytes, CD4+ cells dominated, but during the chronic process there was an increase of CD8+ cells, resulting in a reduced CD4/CD8 ratio. Mitogen-induced activation of isolated mesenteric lymph node cells increased during the chronic inflammation. Our results suggest that in experimental pancreatitis acute inflammatory reactions are followed by a T-lymphocyte-mediated process.

Immunohistochemical characterization of the pancreatic cellular infiltrate in normal pancreas, chronic pancreatitis and pancreatic carcinoma

BACKGROUND/AIMS

Chronic pancreatitis is histologically characterized by an extended fibrosis and infiltration of leukocytes. We intended to differentiate the infiltration to evaluate the inflammatory process.

METHODS

Samples of tissues of normal pancreas (NP, n = 12), of chronic pancreatitis (CP, n = 7), and pancreatic tissues surrounding pancreatic carcinoma (CA, n = 7) were investigated by immunohistochemical staining using the APAAP technique.

RESULTS

In normal pancreas, mononuclear cells (47.1 +/- 26.0 cells/mm2) were observed with a predominance of macrophages (56.3%) and T lymphocytes (31.3%) which were differentiated in CD8+ lymphocytes (9.3 +/- 7.2 cells/ mm2) and CD4+ lymphocytes (6.7 +/- 3.2 cells/mm2). Rarely, plasma cells (5.3%) and B lymphocytes (7.1%) could be detected. In pancreatic tissue of patients with CP and in CA there was a significant increase of mononuclear cells to 264.4 +/- 120.3 cells/mm2 and 284.3 +/- 67.8 cells/mm2, respectively. In both diseases percentages of T lymphocytes (CP: 50.5%; CA: 48.1%) were higher than in normal controls. CD4+/CD8+ ratio of 0.77 in CP and 0.82 in CA demonstrated a predominance of CD8+ cells compared to the peripheral blood. In NP and CA, nearly all T lymphocytes expressed CD45R0 identifying memory cells, while only 58% of T lymphocytes were CD45R0 positive in CP.

CONCLUSION

Our data suggest that the investigated cases of CP were of a common inflammatory type rather than due to an autoimmunological reaction. CD8+ T lymphocytes were the predominant T cell subset in the inflammatory infiltrates in both CP and CA.

Improvement of hepatorenal syndrome with extracorporeal albumin dialysis MARS: results of a prospective, randomized, controlled clinical trial

In hepatorenal syndrome (HRS), renal insufficiency is often progressive, and the prognosis is extremely poor under standard medical therapy. The molecular adsorbent recirculating system (MARS) is a modified dialysis method using an albumin-containing dialysate that is recirculated and perfused online through charcoal and anion-exchanger columns. MARS enables the selective removal of albumin-bound substances. A prospective controlled trial was performed to determine the effect of MARS treatment on 30-day survival in patients with type I HRS at high risk (bilirubin level, > or =15 mg/dL) compared with standard treatment. Thirteen patients with cirrhosis with type I HRS were included from 1997 to 1999. All were Child's class C, with Child-Turcotte-Pugh scores of 12.4 +/- 1. 0, United Network for Organ Sharing status 2A, and total bilirubin values of 25.7 +/- 14.0 mg/dL. Eight patients were treated with the MARS method in addition to hemodiafiltration (HDF) and standard medical therapy, and 5 patients were in the control group (HDF and standard medical treatment alone). None of these patients underwent liver transplantation or received a transjugular intrahepatic portosystemic shunt or vasopressin analogues during the observation period. In the MARS group, 5.2 +/- 3.6 treatments (range, 1 to 10 treatments) were performed for 6 to 8 hours daily per patient. A significant decrease in bilirubin and creatinine levels (P <.01) and increase in serum sodium level and prothrombin activity (P <.01) were observed in the MARS group. Mortality rates were 100% in the control group at day 7 and 62.5% in the MARS group at day 7 and 75% at day 30, respectively (P <.01). We conclude that the removal of albumin-bound substances with the MARS method can contribute to the treatment of type I HRS.

Improvement of hepatorenal syndrome with extracorporeal albumin dialysis MARS: results of a prospective, randomized, controlled clinical trial

In hepatorenal syndrome (HRS), renal insufficiency is often progressive, and the prognosis is extremely poor under standard medical therapy. The molecular adsorbent recirculating system (MARS) is a modified dialysis method using an albumin-containing dialysate that is recirculated and perfused online through charcoal and anion-exchanger columns. MARS enables the selective removal of albumin-bound substances. A prospective controlled trial was performed to determine the effect of MARS treatment on 30-day survival in patients with type I HRS at high risk (bilirubin level, > or =15 mg/dL) compared with standard treatment. Thirteen patients with cirrhosis with type I HRS were included from 1997 to 1999. All were Child's class C, with Child-Turcotte-Pugh scores of 12.4 +/- 1. 0, United Network for Organ Sharing status 2A, and total bilirubin values of 25.7 +/- 14.0 mg/dL. Eight patients were treated with the MARS method in addition to hemodiafiltration (HDF) and standard medical therapy, and 5 patients were in the control group (HDF and standard medical treatment alone). None of these patients underwent liver transplantation or received a transjugular intrahepatic portosystemic shunt or vasopressin analogues during the observation period. In the MARS group, 5.2 +/- 3.6 treatments (range, 1 to 10 treatments) were performed for 6 to 8 hours daily per patient. A significant decrease in bilirubin and creatinine levels (P <.01) and increase in serum sodium level and prothrombin activity (P <.01) were observed in the MARS group. Mortality rates were 100% in the control group at day 7 and 62.5% in the MARS group at day 7 and 75% at day 30, respectively (P <.01). We conclude that the removal of albumin-bound substances with the MARS method can contribute to the treatment of type I HRS.

Serum levels of extracellular matrix in acute pancreatitis

BACKGROUND/AIMS

Elevated levels of serum markers of extracellular matrix, i.e., the amino-terminal procollagen-III-peptide, hyaluronic acid and laminin are found in various diseases. The study aims to examine a panel of these parameters in patients with acute pancreatitis and correlate them with the course and severity of the disease.

METHODOLOGY

We prospectively examined the time-course of procollagen-III-peptide, hyaluronic acid and laminin in 24 consecutive patients with acute necrotizing (n = 13) or edematous (n = 11) pancreatitis. Patients with chronic pancreatitis with (n = 10) or without (n = 17) acute pain, and 6 patients in complete remission after an episode of acute pancreatitis as well as healthy individuals served as controls. In addition, serum levels of collagen VI and undulin were followed in 10 and 9 patients with acute necrotizing pancreatitis, respectively.

RESULTS

The serum concentrations of procollagen-III-peptide, hyaluronic acid and laminin were significantly higher at the onset of acute necrotizing pancreatitis compared to edematous pancreatitis and the controls. They returned to almost normal levels during the course of the disease when the patient recovered, but remained elevated in patients with a lethal course. Laminin allowed us to discriminate between patients with necrotizing pancreatitis from all other forms of pancreatitis on admission (specificity 82%, sensitivity 92%, PPV 86%, NPV 90%). Collagen type VI levels were 2-3-fold higher in sera of patients with acute pancreatitis than in healthy controls, whereas the results for undulin were inconclusive.

CONCLUSIONS

Since markers of matrix metabolism (especially laminin) are differently elevated in acute necrotizing versus edematous pancreatitis, we suggest that they might be used as parameters for the outcome.

Anti-TNF antibody in Crohn's disease--status of information, comments and recommendations of an international working group

The chimeric anti-TNF antibody Remicade (Infliximab) has recently been approved for human use by the FDA and is now available on the market. Since there is considerable interest in this kind of treatment among patients with Crohn's disease, an international working group has summarized the presently available information about efficacy, side effects and possible problems of this treatment. Studies show that Remicade is effective in the treatment of active Crohn's disease, maintaining remission and fistulae. The working group does not see Infliximab as a first-line treatment for Crohn's disease. It may be used in active phase recurrent disease, chronic active disease and fistulae if standard treatment was not successful. For the surveillance special attention has to be given to the unknown malignancy rate of Infliximab. Infusion should be performed in an institution, routinely performing intravenous infusions and a two-hour surveillance of the patients should be guaranteed to recognize anaphylactic reactions or acute side effects. There is presently no information indication that the combination with immunosuppressants might increase risks or side effects of this treatment. Due to the limited information available the working group would prefer to use Remicade in studies only and recommends central collection and documentation of all data on efficacy and side effects for the next year.

Release of hyaluronan and laminin into pancreatic secretions

BACKGROUND

Development of fibrosis characterizes chronic pancreatitis. As it results from deposition of extracellular matrix (ECM) proteins such as hyaluronan (HA) or laminin, the release of these ECM components into blood or pancreatic secretion may be enhanced during the course of chronic pancreatitis.

PATIENTS, MATERIAL AND METHODS

Using immunoassays for HA and laminin, the concentration for these ECM components was measured in pancreatic juice and serum samples from 20 patients with and 20 patients without chronic pancreatitis. Pancreatic calculi of varying size and weight obtained from 13 patients with chronic pancreatitis were also examined for the content of ECM components. Tissue samples from normal pancreas and those showing chronic pancreatitis were investigated immunocytochemically with an antibody to HA synthetase (HAS).

RESULTS

After stimulation with secretin high levels of ECM components were found in the initial washout period in chronic pancreatitis patients as well as in controls. HA levels, however, were seen seven times higher in patients with chronic pancreatitis (mean +/- SEM; 734 +/- 301 vs. 95 +/- 15 microg/l; p < 0.01). Serum HA levels correlated with the duration of chronic pancreatitis and with the levels of HA in pancreatic juice. HA and laminin were detected in the supernatants of pancreatic calculi (laminin 0.70 +/- 0.30 U/l; HA 275 +/- 85 microg/l). Immunocytochemically, strong staining for HAS was found in the duct epithelium and in centroacinar cells of chronic pancreatitis specimens.

CONCLUSION

Demonstration of increased amounts of HA in pancreatic juice of chronic pancreatitis patients stimulated with secretin suggests enhanced production of this ECM component in the chronically inflamed pancreas. The source of HA appears to be the pancreatic ductal epithelium.

Secretory immunoglobulin A in pancreatic juice and pancreatic tissue of patients with chronic pancreatitis

BACKGROUND

The predominance of secretory IgA (S-IgA) in intestinal secretions compared with blood is well established, but concentrations of this protein in pancreatic juice and its origin, especially in chronic pancreatitis, are unknown.

AIMS

To investigate the role of S-IgA in chronic pancreatitis.

PATIENTS

Twenty one patients with chronic pancreatitis (group I), three patients with proven malignancies (group II), and 12 patients without pancreatic disease (group III).

METHODS

Pure human pancreatic juice was collected endoscopically in four fractions after consecutive stimulation with secretin and cholecystokinin (CCK). Samples were analysed for S-IgA, protein, trypsinogen, and proteolytic activity.

RESULTS

The S-IgA level was significant increased in fraction 1 of pancreatic juice of group I (1210 (1411) ng/ml) compared with controls (33 (70) ng/ml). Protein concentrations and trypsinogen content were lower in group I than in the other groups. Proteolytic activity could be observed in 53% of all 133 pancreatic juice samples, but in 87% of fraction 1. In pancreatic tissue of three patients with chronic pancreatitis both IgA and secretory component were detected by immunohistology. Expression of the secretory component by human pancreatic epithelial cells was increased in patients with chronic pancreatitis compared with normal controls. The concentration of S-IgA in pancreatic juice did not correlate with the serum S-IgA level. In contrast, serum levels of S-IgA were decreased in patients with chronic pancreatitis.

CONCLUSION

There are high levels of S-IgA in human pancreatic juice following chronic inflammation and a protective role is suggested for this immunoglobulin.

Production of trypsin by cells of the exocrine pancreas is paralleled by the expression of the KH protein vigilin

Vigilin, a protein with a continuous series of 14 KH motifs, forms part of a multiprotein complex containing tRNA. Several lines of evidence have suggested that vigilin expression is enhanced in those cells which were actively engaged in protein synthesis. Accordingly, we show here by immunoelectronmicroscopy a close association of vigilin with the rough endoplasmic reticulum in rat pancreatic cells. Histological examination of these cells furthermore demonstrates the highest intensity of vigilin staining in the perinuclear, intranuclear, and basolateral regions where the endoplasmic reticulum is mainly amassed. In vivo challenge of starving rats fed prior to sacrifice raised in parallel the protein levels of both trypsin and vigilin when compared to unchallenged animals and was associated with enhanced expression of the vigilin gene. In contrast, in human and rat cell lines of pancreatic tumors with a constitutively high expression of vigilin no further stimulation by cholecystokinin treatment could be achieved. Our data provide circumstantial evidence that vigilin may play a crucial role in the ability of an organ, e.g., pancreas, to cope with the physiological demand to upregulate protein synthesis.

Cu/Zn-SOD in human pancreatic tissue and pancreatic juice

CONCLUSION

Cu/Zn-SOD is present in pancreatic juice and tissue. Immunohistochemical studies reveal a localization of this enzyme in islet, duct, and centroacinar cells, but to a much lower extent in pancreatic acinar cells.

BACKGROUND

It is generally accepted that oxygen radicals are involved in the pathogenesis of acute and chronic pancreatitis. An imbalance of radical-generating and radical-scavenging processes is thought to lead to the damage of pancreatic acinar cells that initiate the autodigestion of the whole organ.

METHODS

We investigated the distribution pattern of the cytosolic radical-scavenging enzyme, copper/zinc-superoxide dismutase (Cu/Zn-SOD), in pancreatic juice and tissue. In patients with chronic pancreatitis or pancreatic malignancies, Cu-Zn-SOD was quantitated in different fractions of pancreatic juice by means of an enzyme immunoassay using two Cu/Zn-SOD-specific monoclonal antibodies. Cryostat or paraffin sections of pancreatic tissue were analyzed by immunohistochemical techniques.

RESULTS

We found this enzyme to be present in the first secretin-triggered fraction of endoscopically obtained pancreatic juice in concentrations similar to serum. In contrast, after cholecystokinin stimulation, only low levels could be found in pancreatic juice, indicating that this enzyme is not actively secreted. Interestingly, pancreatic juice of patients with chronic pancreatitis or pancreas tumor contained higher levels (25-29 ng/mL) of Cu/Zn-SOD than juice of controls without pancreatic diseases (15 ng/mL). Immunohistochemical studies of Cu/Zn-SOD in pancreatic tissue revealed a more intense staining of duct cells, islet cells, and centroacinar cells, whereas acinar cells showed almost no staining for Cu/Zn-SOD.

Pancreatic fibrosis in experimental pancreatitis induced by dibutyltin dichloride

BACKGROUND & AIMS

Regulatory mechanisms in chronic pancreatitis finally resulting in pancreatic fibrosis cannot be studied sufficiently in human pancreas. Results of a new pancreatitis model in rats suitable for investigation of the processes leading to pancreatic fibrosis are presented.

METHODS

Experimental pancreatitis was induced by intravenous application of 8 mg/kg body wt dibutyltin dichloride. Pancreatitis was characterized by histology, serum parameters, and immunohistochemistry, detecting inflammatory cells. Gene expression of collagen type I and transforming growth factor beta1 was shown by Northern blot analysis.

RESULTS

Dibutyltin dichloride induced an acute edematous pancreatitis within 24 hours. Extensive infiltration with mononuclear cells could be observed after day 7 followed by the development of fibrosis. Parallel to the cell infiltration, an upregulation of messenger RNA-encoding collagen type I and transforming growth factor beta1 could be shown. An active inflammatory process could be shown until the end of the observation period, i.e., 2 months.

CONCLUSIONS

The findings suggest that dibutyltin dichloride-induced pancreatitis in rats is suitable to study cellular interactions and mediators involved in the development of pancreatic fibrosis.

[Relationship between secretory IgA in pancreatic secretions, in pancreatic tissue, and in the serum of patients with chronic pancreatitis]

In five patients with chronic pancreatitis we found secretory IgA (sIgA) in the pancreatic juice. In four control persons this was seen only in one case. In pancreatic tissue of three patients with chronic pancreatitis we detected both, IgA and secretory component by immunohistology. We suggest that sIgA in the pancreatic juice was partly produced in the pancreas.

[Follow-up study of the development of autoantibodies in patients with chronic inflammatory bowel disease under anti-CD4 therapy]

7 of 22 patients with chronic inflammatory bowel diseases (Crohn's disease, ulcerative colitis) were treated with an anti-CD4-mAb. In the immunological monitoring the amounts of autoantibodies to pancreatic acini cells, to intestinal goblet cells, to granulocytes with perinuclear fluorescence pattern were examined and human anti-mouse-antibodies were measured. After anti-CD4 therapy the production of autoantibodies was widely unchanged. Therefore its use as parameter in the follow-up is restricted.

[Treatment of autoimmune diseases and graft rejection with anti-CD4 antibodies]

Based on the experience that T helper lymphocytes play an important part in the initiation and maintenance of various autoimmune diseases and also in graft rejection, novel therapeutic approaches have been developed and are under investigation. They are aimed at selective inhibition of T cells whose activation is unwanted. Useful tools for this purpose are monoclonal antibodies to cell surface molecules which are restricted to certain cell populations. In this review the concept of treatment with antibodies to CD4-a surface molecule characteristic of T helper lymphocytes-is discussed. Encouraged by experimental experiences obtained during the past years, a series of case reports were published and clinical pilot studies have been performed, the preliminary results of which are now becoming available. Anti-CD4 therapy appears to be a promising approach. Short-lasting effects can be separated from long-lived effects. The latter are not easy to explain, although hypotheses have been developed still requiring more detailed experimental confirmation.

[Comparison of the drop and capillary technics of the leukocyte migration inhibition test in the detection of sensitization to candidin]

15 test persons with a positive and 3 with a negative intradermal test of candidin were examined with two modifications of the migration inhibition test. In these cases the agarose droplet test proved to be somewhat more sensitive in comparison to the capillary method. There were no correlations between the size of the cutaneous test reaction and the adequate migration index. The droplet test using culture residues (lymphokin assay) was less evident in comparison to the direct method. The two techniques (droplet test, capillary method) are well suited for the proof of cell-mediated immune reactions to candidin and other comparable antigens, respectively.

[Experiences with the Antibody-coated Bacteria Test in the diagnosis of urinary tract infections]

We examined 67 cases with significant bacteriuria for the presence of antibody-loaded bacteria which shall refer to an infection of the upper urinary tract. With the help of this method we could diagnose 43 of the 45 cases with acute and chronic pyelonephritis. Three of the 22 cases with a bacteriuria of other genesis proved as falsely positive. The antibody-coated-bacteria-test should be used as diagnostic remedy in infections of the urinary tract as well as for course controls and as screening test in the clinic.

[Changes in the synovial membrane in early diagnosed cases of rheumatoid arthritis. II. Immunohistochemical and serological studies]

To extend the histologic-histochemical examinations on so-called early cases of rheumatoid arthritis (RA, Geiler and Emmrich 1980) additional immuno-histochemical and serological tests were carried out on the same subjects. The purpose was to find out to what extent the well-known humoral immunological abnormalities of RA cases with fully developed disease (so-called late cases) occur in the early stage of RA. It was also aimed to determine their diagnostic and pathogenetic significance. The synovial membranes were tested immuno-histochemically for rheumatoid factor, immunoglobulins, and complement fixation for the complement factors C3, C4 and C9. In the serum the rheumatoid factor was assayed by the latex test and its immuno-globulin class specificity by means of an immunofluorescence test. In contrast to observations in the late cases, rheumatoid factors, immuno-globulins and complement deposits are found less often. In the class specificity test of rheumatoid factor in the serum there are considerably more positive cases than with the latex test. In the synovial membrane and in the serum there are positive cases also in juvenile RA-cases. For the diagnosis of early cases the immuno-histochemical demonstration of the rheumatoid factor in the synovial membrane is of great importance. The diagnosis RA may thereby the secured. --In the pathogenesis the accumulation of vasculitides with deposits of immune-complexes may be important. Possibly a vasculitis induced by immune-complexes represents the initial reaction of the rheumatoid synovitis. Since in the early cases little synthesis and deposits of immuno-globulins, rheumatoid factors and complements are found, it may be assumed that the more active humoral immunological activity of the synovial membrane of the late cases develops slowly during the course of the disease.

[Obstetrical analgesia with tramadol]

Parenteral analgesia with Tramal was performed in 23 normal deliveries. The results were compared with a group of normal deliveries in which analgesia was achieved with pethidine. Both medicaments excerted an identical analgetic efficiency. No adverse side effects were observed with Tramal concerning the follow-up of labour or the newborn. Tramal can be recommended for obstetrical analgesia since it does not excert inhibitory effects upon the respiratory center.

[Synovial membrane changes in early rheumatoid arthritis. I. Histological studies]

The histological and histochemical findings in synovial membranes of 13 patients with early rheumatoid arthritis (duration not more than 6 months; clinical follow-up at least 2 years) have been compared with 16 late cases of definite RA (ARA criteria). The authors intended to investigate the dynamic evolution of rheumatoid synovitis and to analyze the full-fledged changes with reference to diagnosis and pathogenesis of RA. Although the basic pattern of reaction is the same, the following peculiarities are found in early RA: 1) A band-like mucoid swelling of the synovial adventitia, histochemically with increase of acid glucosaminoglycans; 2) more frequent occurrence of vasculitis; 3) less marked infiltration with lymphocytes and plasma cells; 4) absence of gross fibrin insudation and granulocyte infiltration; 5) absence of diffuse fibrosis and hyalinosis. For diagnostic purposes it is also important that proliferative reactions can be found but are much less marked than in late cases. In conclusion, the early morphological findings do not allow more than the suspicion of RA. The combined mucoid swelling of the ground substance and vasculitis together with further signs of proliferation and exsudation are most important. With reference to the pathogenesis of RA, the authors insist on the frequent vasculitic changes and the early occurrence of immuno-competent cells which are the cytological condition of immunological reactions.

[Retroperitoneal lipoma-aspects on differential diagnosis (author's transl)]

A laparotomy has been performed in a 49 years old woman. Preoperatively a large ovarian cystoma has been diagnosed. Factitiously a retroperitoneal lipoma was extirpated with a weight of 12,5 kg.