Cytokine Production by Intestinal Intraepithelial Lymphocyte Subsets in Celiac Disease

One of the earliest signs of mucosal immune activation in celiac disease (CD) is an increase in the intraepithelial lymphocyte (IEL) count in the small intestinal epithelium. Though most of those IELs express T cell receptor (TcR)- chains, CD is characterized by an increase in TcR- ⁺ IELs and by the loss of CD3^– IELs. There is currently little evidence that these changes in IEL subset distribution are of relevance in the pathogenesis of CD. We aimed to determine the pattern of cytokine production by IEL subsets isolated from duodenal biopsy specimens from control subjects and CD patients at different stages of the disease. We quantified the capacity of IEL subsets to produce IFN-, TNF-, IL-2, IL-4, and IL-10 by intracellular staining by flow cytometry. All IEL subsets studied displayed a type I cytokine profile in both CD and control subjects, with TcR-⁺ IELs being the main IFN- producers. Untreated CD exhibited a trend toward a superior accumulation of IFN- per cell but a reduced proportion of INF-⁺ cells in vitro in association with a significantly increased apoptotic rate of IELs. IL-4 was almost undetectable in all cases and IL-10 showed a tendency to increase in treated and silent celiac patients. IEL subsets have a similar Th1 profile in controls and CD patients, and the superior in vitro apoptosis of IELs from CD patients may reflect their superior in vivo activation. The induction of IL-10-dependent regulatory Tr1 responses may be of potential clinical significance in this disease and merits further investigation.     

Acute hematologic effects of interferon alpha,interferon gamma,tumor necrosis factor alpha and Interleukin 2

Summary This study was designed to investigate acute effects of various doses of the cytokines IFN-alpha, IFN-gamma Interleukin 2 and tumor necrosis factor alpha on white blood cell differential counts. Before initiation of phase II trials, a dose-determination phase was performed, where three different dose levels of each cytokine were applied as a single dose. White blood cell differential counts were assessed immediately before and 2, 12, 24, 48 and 168 h after injection. Patients enrolled suffered from metastatic cancer or chronic active hepatitis. In addition, IFN-alpha was administered to five healthy volunteers. Results indicate that cytokines cause rapid and transient changes in the numbers of leukocyte subsets. Hematologic changes were cell-type- and cytokine-specific: transient lymphopenia was observed after administration of all four cytokines, reaching a nadir 12 to 24 h after subcutaneous injection. Administration of TNF-alpha and IFN-gamma also caused transient monocytopenia. Neutrophilia developed after administration of Interleukin 2, IFN-alpha and TNF-alpha. We conclude that cytokines play a key role in the regulation of peripheral blood cell traffic by their capacity to influence homing patterns of peripheral blood leukocytes.     

Presence of interferon and anti-interferon in patients with systemic lupus erythematosus

Summary Sera from 61 patients with systemic lupus erythematosus (SLE) were serially screened over a period of at least 2 years for IFN and anti-IFN antibodies. IFN concentrations were measured both with a cytopathic effect assay and a more sensitive radioimmunoassay. Of the patients 15% (9/61) had IFN in their serum at one or more occasions as measured in the bioassay (6 IU/ml); employing a RIA (1 IU/ml) 28% (17/61) of the patients studied were positive for IFN-. Fifteen patients had a measurable interferonemia over 2–16 months; only two patients had detectable IFN in their serum at only one occasion. In five patients, hourly and daily variations of the IFN titer as measured by RIA were found to amount to less than 80%. The IFN activity found in these sera was characterized as IFN- by means of acid stability, cross-reactivity on heterologous cells, trypsin sensitivity, and neutralization by homologous and heterologous antisera. IFN antibodies were quantified with a neutralization bioassay, an ELISA, and a radioimmunoassay. Of the 61 patients 5% (3) possessed high titers of anti-IFN antibodies which persisted over 2 years. The IFN- antibody positive patients had an inactive form of the disease over years without visceral involvement but decreased serum complement levels (C4, C3, CH50) and repeated episodes of Quincke-like edema.     

Effect of Losartan, an Angiotensin II Antagonist, on Hepatic Fibrosis Induced by CCl4 in Rats

In addition to regulating blood pressure and body fluid homeostasis, the renin-angiotensin system (RAS) is also involved in hepatic fibrogenesis. We aimed to investigate the effect of losartan, an angiotensin II (Ang II) antagonist, on CCl4-induced hepatic fibrosis in rats. Hepatic fibrosis was induced by a subcutaneous injection with 50% CCl4 in Sprague-Dawley rats. The amount of CCl4 administered was 1 mg/kg. Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels in plasma and hydroxyproline (Hyp) contents in liver tissue were assayed by spectrophotometry. Hyaluronic acid (HA) and procollagen III (PC III) were assessed by radioimmunoassay. Tumor necrosis factor-alpha (TNF-alpha) and transforming growth factor-beta1 (TGF-beta1) levels in culture supernatants of Kupffer cells (KCs) stimulated with Ang II was determined by ELISA. Liver samples collected after 12 weeks of CCl4 treatment were stained with hematoxylin and eosin, then scored. Losartan (2.5, 5, and 10 mg x kg(-1), ig) and captopril (100 mg x kg(-1), ig) significantly decreased liver and spleen indexes, serum transaminase (AST, ALT) activities, HA and PC III levels, and Hyp contents in liver tissue in rats of hepatic fibrosis. Histopathological scores showed that losartan had an inhibitory effect on the progression of hepatic fibrosis. In in vitro experiments, losartan (1 x 10(-9) - 1 x 10(-5) M) significantly reduced TNF-alpha and TGF-beta1 levels in culture supernatants of KCs, but captopril (1 x 10(-5) M) did not. The results showed that losartan significantly inhibited the progression of hepatic fibrosis induced by CCl4, and the inhibitory effect of losartan on hepatic fibrosis might be associated with its ability to inhibit the production of TNF-alpha and TGF-beta1 by activated KCs.     

Detection of tumour necrosis factor alpha and interleukin-1 beta in the rheumatoid osteoarthritic cartilage-pannus junction by immunohistochemical methods

Summary During inflammation the rheumatoid synovial membrane is invaded by a number of different cell types. When activated most of these cells produce cytokines including tumor necrosis factor alpha (TNF) and interleukin-1 beta (IL-1 ). These cytoiines are believed to stimulate production of degradative enzymes and disturb the equilibrium between such enzymes and their inhibitors resulting in tissue damage. In this study we investigated the localisation of TNF and IL-1 at the cartilage-pannus junction (CPJ). Here, cytokines are well placed to influence the integrity of articular cartilage. Tissue was derived from advanced rheumatoid (RA) and, as a comparison, osteoarthritic (OA) joints at the time of replacement surgery (arthroplasty). Antibody staining of fixed serial sections of tissue localised cells that were associated with IL-1 and TNF. Cell markers for macrophages and endothelial cells were included to provide positive identification of the cytokine-associated cells. Analysis of these sections revealed that both TNF and IL-1 were associated with macrophages, particularly those in the synovium overlying cartilage (pannus) and endothelial cells. Positive staining was seen at the CPJ in RA and in similarly located tissue in OA. The similar distribution of cytokines in OA was unexpected even if the overall numbers of tissue and infiltrating cells in the CPJ were different in the two diseases. This highlights the possible role played by endogenous inhibitors [1, 2] in influencing the degree of cytokine activity necessary to explain the different pathogenic mechanisms in RA and OA.     

Gabexate mesilate, a synthetic protease inhibitor, attenuates carbon tetrachloride-induced liver injury in rats

Background Gabexate mesilate, a synthetic protease inhibitor, is used to treat acute pancreatitis and disseminated intravascular coagulation because it inhibits various serine proteases; however, whether gabexate mesilate prevents acute liver failure has not yet been studied. The aim of the present study was to investigate the effect of gabexate mesilate in carbon tetrachloride (CCl₄)-induced liver injury in rats.Methods Acute hepatic failure was induced by administration of CCl₄ intragastrically to male Sprague–Dawley rats. The effects of gabexate mesilate were examined in terms of serum transaminase levels, liver histology, and the prognosis of rats.Results Gabexate mesilate treatment significantly decreased the elevation of serum transaminase levels and improved liver histology 24h after the administration of CCl₄ (0.2ml/100g rat weight). Plasma tumor necrosis factor- (TNF-) and interleukin-1 (IL-1) decreased significantly in the gabexate mesilate-treated rats compared with saline-treated rats. Gabexate mesilate treatment also significantly improved survival rate after a lethal dose of CCl₄ (0.5ml/100g rat weight) from 0% to 20%.Conclusions Gabexate mesilate treatment attenuated CCl₄-induced liver injury via a suppression of proinflammatory cytokine production. In addition, these investigations suggest that gabexate mesilate treatment may provide therapeutic strategies for human acute liver failure.     

Human Leukocyte Interferon-α Treatment for Chronic HCV-Related Hepatitis in Hemophilic Patients Previously Intolerant to Other Interferons-α

Thirty patients affected by hemophilia A or B or von-Willebrand's disease and chronic posttransfusional active HCV hepatitis who developed major side effects during the course of a previous treatment with recombinant interferon- (IFN-) were studied. In all patients IFN- therapy had to be discontinued and those who achieved a primary serologic and viral response to HCV relapsed within a few months. After a washout period, patients were retreated with human leukocyte IFN-, 6 MU thrice weekly for 12 months. In about 90% of patients, a primary response, with normal AST and GGT values and undetectable HCV-RNA, was achieved within the third month of treatment and for the entire duration of treatment none of the patients had to discontinue therapy because of severe adverse reactions. During posttherapy follow-up only one patient relapsed. The human leukocyte IFN- regimen looks to be very effective and safe for carriers of inherited clotting disorders who developed major side effects with recombinant IFN- therapy for HCV-related chronic hepatitis.     

Deficient IFNα production in hairy cell leukemia

Summary Since the application of low doses of IFN-alpha is necessary to maintain remissions in Hairy Cell Leukemia (HCL) it is of interest whether peripheral blood mononuclear cells (MNC) of HCL patients can be induced in vitro to produce IFN-alpha. 9 patients suffering from advanced HCL were included in the study. The diagnoses were confirmed by characteristic findings in peripheral blood and bone marrow biopsies. For IFN treatment we initially used natural IFN-alpha (Bioferon) and switched later to recombinant IFN-alpha₂ (Boehringer). MNC of 5 patients before IFN therapy and of 6 patients during IFN therapy (2–47 weeks) were induced by phythemagglutinin (PHA), Corynebacterium parvum (C.p.), and sendai virus (SV). PHA is known to induce IFN-gamma. Both, C.p. and SV induced IFN-alpha but no IFN-gamma in MNC of healthy controls and of IFN treated breast cancer patients. In HCL patients normal antiviral activities could be induced by PHA. Zero or only low antiviral activities could be induced in MNC from 9 patients tested on 22 occasions. It is concluded that MNC from patients with advanced HCL can be induced to produce IFN-gamma but no IFN-alpha. Since IFN-alpha but not IFN-gamma is produced by monocytes it is likely that reduced numbers of monocytes which were found in our HCL patients before and during IFN treatment account for the described deficiency of IFN-alpha production.     

Expression and secretion of alpha1-proteinase inhibitor are regulated by proinflammatory cytokines in human pancreatic islet cells

Aims/hypothesis Alpha1-proteinase inhibitor (1-PI) has been considered a key player in inflammatory processes. In humans, the main production site of 1-PI is the liver, but other tissues, including pancreatic islets, also synthesise this molecule. The aims of this study were to assess the islet cell types that produce 1-PI, to determine whether 1-PI is actually secreted by islet cells, and to assess how its production and/or secretion are regulated.Methods Expression of 1-PI in human islet cells was assessed by immunofluorescence, electron microscopy and western blotting. Release of 1-PI was analysed by reverse haemolytic plaque assay and ELISA. The effects of cytokines on 1-PI synthesis and secretion were tested.Results Immunofluorescence showed that alpha and delta cells do express 1-PI, whereas beta cells do not. By electron microscopy, we demonstrated a colocalisation of 1-PI with glucagon and somatostatin within secretory granules. Immunolabelling also revealed localisation of 1-PI within the Golgi apparatus, related vesicles and lysosomal structures. The expression of 1-PI in islet cells was also demonstrated by western blotting and ELISA of protein extracts. ELISA and reverse haemolytic plaque assay showed that 1-PI is secreted into the culture medium. Treatment of islet cells with IL-1 and oncostatin M for 4 days increased the production and release of 1-PI.Conclusions/interpretation Our results demonstrate that 1-PI is expressed by the alpha and delta cells of human islets, and that proinflammatory cytokines enhance the production and release of this inhibitor.     

A prospective comparison between treatment with phlebotomy alone and with interferon-alpha in patients with polycythemia vera

Summary Interferon alpha (-IFN) is increasingly used for the treatment of patients affected by polycythemia vera (PV). As prior studies are difficult to interpret in view of the lack of appropriate controls, we undertook a randomized comparison of lymphoblastoid -IFN ( n–1 IFN) treatment against venesection treatment alone. In a crossover trial, we treated 22 PV patients alternatively for 5 months each with 3 MU/day sc of n–1 IFN and phlebotomy alone. During IFN treatment, red blood cell count and hematocrit level were well controlled in both trial groups, reducing or eliminating the need for phlebotomy in all patients; furthermore, platelet number and white blood cell count declined during -IFN therapy. In addition, the number of symptomatic patients was greatly reduced, and in six patients a reduction in splenic size was observed. Finally, the only patient with chromosomal abnormalities showed a complete cytogenetic conversion after 5 months of -IFN therapy. Thus, for the first time, our results provide the unequivocal demonstration that -IFN is superior to phlebotomy in controlling the pathologic expansion of erythroid elements and all the clinical aspects of this disease.     

Correlation Between Stellate Cell Activation and Serum Fibrosis Markers in Choline-Deficient l-Amino Acid-Defined Diet-Induced Rat Liver Fibrosis

The aim of this study was to investigate the association of stellate cell activation with serum fibrosis markers in a rat model of hepatic fibrosis prepared using a choline-deficient l-amino acid (CDAA) defined diet. CDAA diet administration resulted in increased liver hydroxyproline contents in a time-dependent manner with activated stellate cells, expressing -smooth muscle actin (-SMA) as well as increased serum concentrations of amino-terminal procollagen type III peptide (PIIIP) and the 7S fragment of type IV collagen. Hydroxyproline content of the liver showed a closer correlation with the serum 7S (r = 0.75, P < 0.01) concentration than with the serum PIIIP (r = 0.51, P < 0.01) concentration. The percent area of -SMA-positive cells showed stronger correlation with the serum PIIIP concentration (r = 0.85, P < 0.01) than with the 7S concentration (r = 0.50, P < 0.01). These results indicate that the serum PIIIP concentration reflects the activity of fibrogenesis, while the serum 7S concentration reflects the accumulation of collagen fibers in the liver.     

Triplication (/ααα<Superscript>Anti3.7</Superscript>) or deletion (-α<Superscript>3.7</Superscript>/) association in Argentinian β-thalassemic carriers

Prevalence of alpha gene triplication or deletion in -thalassemia carriers was studied in 109 unrelated individuals in Rosario, Argentina. In different populations -^3.7 allele presents a higher prevalence than ^anti3.7; thus, -thalassemia associated with -thalassemia is more frequently observed. Nevertheless, this event was detected in only one case (0.9%), while the association with alpha triplication was present in two subjects (1.8%).     

Large-scale studies of the association between variation at the TNF/LTA locus and susceptibility to type 2 diabetes

Aims/hypothesis The proinflammatory cytokine TNF- has been implicated in the pathogenesis of insulin resistance and type 2 diabetes, and variation in the gene encoding TNF- (TNF) has shown inconsistent associations with susceptibility to both conditions. Additionally, the coding non-synonymous variant T60N in the neighbouring LTA gene has been reported to be associated with type 2 diabetes. The present study aimed to obtain a robust assessment of the role of variation in the tightly linked TNF/LTA region in diabetes susceptibility by genotyping TNF and LTA variants in large case-control resources.Materials and methods The G-308A and G-238A TNF promoter variants and the LTA T60N polymorphism were genotyped in two UK case samples that were ascertained for positive family history and/or early onset of type 2 diabetes (combined n=858) and in 1,257 ethnically matched controls.Results There were no significant associations between the T60N, G-308A or G-238A genotype and type 2 diabetes in the combined analysis (exact Cochran–Mantel–Haenszel statistic for ordered genotypes for T60N, p=0.69; for G-308A, p=0.51; for G-238A, p=0.16).Conclusions/interpretation The present study, one of the largest association analyses yet reported at this locus, provides no evidence that the specific TNF or LTA variants examined influence susceptibility to type 2 diabetes. More comprehensive studies of the TNF/LTA locus in substantially larger sample sets are required to establish whether genome sequence variation at this locus truly influences susceptibility to type 2 diabetes.     

Lack of association of tumor necrosis factor-alpha gene polymorphisms with disease susceptibility and severity in Behçet’s disease

Although it has been reported that the MHC class I molecule, HLA-B51, is a risk factor for Behçets disease (BD), contribution of the tumor necrosis factor (TNF) genes, which are located in the vicinity of the HLA-B locus, to the genetic susceptibility for BD has yet to be elucidated. The purpose of this study was to analyze the effect of TNF- promoter polymorphisms at positions –308, –238 and –376 on the susceptibility, severity and clinical features of BD. The TNF- gene sequences from 107 patients with BD and 102 healthy subjects were amplified by the polymerase chain reaction. Sequence analysis of the TNF- gene locus, which contains promoter polymorphisms at positions –376, –308, and –238, was performed with a DNA sequencing kit on automated sequencer. The patients were classified according to disease severity and clinical features. Serum TNF- level in the study groups was measured by sandwich enzyme immunoassay. In patients with BD the frequencies of TNF- –308 (19.4% vs 18.4%), –238 (3.7% vs 5.9%), and –376 (0.9% vs 2.9%) gene polymorphisms were not found to be significantly different from those in healthy subjects. The TNF- gene polymorphisms did not show any association with disease severity or clinical features. Serum TNF- level was significantly higher in patients with BD than in healthy controls (3.10±1.45 pg/ml vs 2.43±1.94 pg/ml, P < 0.01). Serum TNF- level was not found to be significantly associated with disease severity, activity, clinical findings and TNF- genotypes. The results of this study suggest that the TNF- gene polymorphisms are unlikely to play an important role in the pathogenesis and severity of BD.     

Antiproliferative effects of interferonγ in combination withα-difluoromethylornithine on human carcinoma cell cultures

The antiproliferative effects of human recombinant interferon (IFN) in combination with -difluoromethylornithine (DFMO) or as single agents were assessed on human cell cultures derived from carcinomas of the breast (MCF-7), the ovary (EFO-27) or the kidneys (EGI-4). Results were obtained in proliferation assays by direct cell counting. The cell lines differed considerably in their sensitivities to the antiproliferative effect of IFN as compared by the 50% inhibition doses of the growth (ID₅₀). In contrast to the findings with IFN, similar antiproliferative effects resulted from the application of comparable doses of DFMO. While IFN induced cytotoxic effects in EGI-4 cells, DFMO produced only cytostatic actions in the cell lines analyzed. Synergistic growth inhibition resulted from the combined application of IFN and DFMO in EFO-27 cell cultures. This finding was most pronounced after treatment with IFN or DFMO doses below the respective ID₅₀ values. However, antagonistic effects occurred in cells of the line EGI-4 after DFMO had been combined with IFN at concentrations below the cytotoxic dose range. Within the sensitivity of our proliferation assay, no synergistic interactions were found in MCF-7 cell cultures. In the cell lines tested, no relation between the sensitivity for the single agents and the effectivity of the drug combination was identified. Despite promising synergistic effects in the moderately IFN-sensitive ovarian carcinoma cell line EFO-27, the efficacy of the IFN/DFMO combination was restrained by possible antagonistic effects as demonstrated in the highly IFN-sensitive EGI-4 renal carcinoma cell cultures. We conclude that the differential interaction patterns in the cell cultures analyzed preclude general suggestions for clinical studies using IFN and DFMO.Abbreviations IFN interferon - DFMO difluoromethylornithine This work was part of the doctoral thesis of Mariam Klouche     

Long-Term Efficacy of Interferon-alpha and Ursodeoxycholic Acid in Treatment of Chronic Type C Hepatitis

Interferon-alpha (IFN) and ursodeoxycholic acid(UDCA) combined have a controversial role in thetreatment of chronic type C hepatitis. We studied thelong-term efficacy of both drugs alone or incombination. In a three-year period, 108 patients wererandomized into three treatment arms: (1) IFN alone 3 MUthree times a week (N = 49), (2) IFN 3 MU three times aweek + UDCA 250 mg twice a day (N = 45), and (3) UDCA alone 250 mg twice a day (N = 14). Response wasdefined as complete normalization of serum ALT. For theresponders at the end of six months, the treatment wasrun to 12 months. Nonresponders (NRs) of the first group were crossed over to combinationand NRs of the combination received 6 MU three times aweek IFN + UDCA for the next six months. The enrollmentto the UDCA alone arm was stopped early, since only 1/14 normalized serum ALT at the end of thirdmonth. However, 12/14 completed six months and 11 NRsreceived IFN 3 MU three times a week alone for the nextsix months. Twelve discontinued treatment due to side effects. Responders were followed-upuntreated for 18 months. Sustained response (SR) wasdefined as persistence of normal serum ALT levels inthis period. At the end of six months, 22/45 (48%) from the IFN-alone and 23/39 (58%) from thecombination group responded. Twenty NRs from former and15 of latter group were crossed over. While none of the20 from the IFN-alone group responded to thecombination, 1/15 NRs of the combination group responded todose escalation. SR was achieved in 9/45 (20%) of theIFN alone and 7/39 (18%) of the combination group. Themean time form the end of the treatment to the relapse was not different between the groups.Five of 11 UDCA NRs responded to IFN with SR in 2. Itwas concluded that UDCA as a single agent is ineffectivein achieving response in the treatment of chronic type C hepatitis. Combined with IFN, itincreases response rate insignificantly although this isnot sustained.     

Temperature and Serum Proinflammatory Cytokine Changes in Patients with NSCLC after BAL

We examined the effects of bronchoalveolar lavage (BAL) and BAL fluid characteristics on the systemic proinflammatory cytokine expression and their relation to clinical and laboratory findings. Thirty patients suspected to have lung cancer were subjected to fiber-optic bronchoscopy (FOB) and BAL. Clinical and laboratory findings were determined at baseline, 4 h, and 24 h, including lung auscultation, temperature, chest X-ray, WBC, neutrophils, and serum IL-1, IL-6, and TNF-. BAL fluid characteristics were determined including cytokine levels. Fifteen volunteers served as controls to determine serum variation of the same cytokines. Significant temperature elevation was defined as 1°C increase compared to baseline. BAL was associated with temperature and serum TNF- and IL-6 but not IL-1 increase at 4 h. Four patients (13.3%) developed temperature over 38°C. In controls there were no significant changes between baseline and 24 h measurements for the same cytokines. Eleven patients (36.6%) developed a significant temperature elevation 4 h after BAL. These patients had a statistically significant (p < 0.05) increase in serum IL-6 at 4 h and in TNF- at both 4 and 24 h after BAL compared with the nonsignificant temperature increase group. BAL characteristics were not different between the two groups. On the other hand, BAL fluid IL-6 and TNF- levels were significantly higher (p < 0.05) in the nonfever group. Significant temperature increase was observed in 36.6% of the patients undergoing BAL and associated with significant serum TNF- and IL-6 increase at 4 h. Lung cytokines levels, alveolar macrophages, and BAL fluid characteristics are not related to temperature and serum proinflammatory cytokine increase. The hypothesis of alveolar macrophages derive from cytokine production and shift to the systemic circulation cannot be supported by our data. Abbreviations: NSCLC = non-small-cell lung carcinoma, BAL = bronchoalveolar lavage, FOB = fiber-optic bronchoscopy, IL-6 = interleukin 6, IL-1 = interleukin 1-beta, TNF- = tumor necrosis factor alpha, WBC = white blood cells, G-CSF = granulocyte colony stimulating factor, IM = intramuscular, ECG = electrocardiogram.