Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0010346 (Crohn's disease)
 21,615 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A large body of evidence indicates the existence of functionally polarized CD4+ T-cell responses based on their profile of cytokine secretion. Type 1 T helper (Th1) cells produce interferon-gamma, interleukin (IL)-2, and tumour necrosis factor (TNF)-beta, which activate macrophages and are responsible for cell-mediated immunity and phagocyte-dependent protective responses. By contrast, type 2 Th (Th2) cells produce IL-4, IL-5, IL-10, and IL-13, which are responsible for strong antibody production, eosinophil activation, and inhibition of several macrophage functions, thus providing phagocyte-independent protective responses. Th1 cells mainly develop following infections by intracellular bacteria and some viruses, whereas Th2 cells predominate in response to infestations by gastrointestinal nematodes. Polarized Th1 and Th2 cells not only exhibit different functional properties, but also show the preferential expression of some activation markers and distinct transcription factors. Several mechanisms may influence the Th cell differentiation, which include the cytokine profile of "natural immunity" evoked by different offending agents, the nature of the peptide ligand, as well as the activity of some costimulatory molecules and microenvironmentally secreted hormones, in the context of the individual genetic background. In addition to playing different roles in protection, polarized Th1-type and Th2-type responses are also responsible for different types of immunopathological reactions. Th1 cells are involved in the pathogenesis of organ-specific autoimmune disorders, Crohn's disease, Helicobacter pylori-induced peptic ulcer, acute kidney allograft rejection, and unexplained recurrent abortions. In contrast, allergen-specific Th2 responses are responsible for atopic disorders in genetically susceptible individuals. Moreover, Th2 responses against still unknown antigens predominate in Omenn's syndrome, idiopathic pulmonary fibrosis, and progressive systemic sclerosis. Finally, the prevalence of Th2 responses may play some role in a more rapid evolution of human immunodeficiency virus infection to the full-blown disease. The Th1/Th2 paradigm also provides the rationale for the development of new types of vaccines against infectious agents and of novel strategies for the therapy of allergic and autoimmune disorders.
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PMID:Th1/Th2 cells. 1057 23

Dietetic treatment of Crohn's disease has the objective to calm down the gut either by a polymeric or elemental diet. In superacute conditions also total parenteral nutrition can be used. In the quiescent stage the patient must have an adequate energy intake and a low-residue (low-fibre) diet. As to medication, sulfasalazine which has some side-effects is abandoned and 5-ASA (5-aminosalicylic acid) preparations are used, either by the oral route or in enemas, while 4-ASA is little used in this country and is known as PAS. The administration of corticoids which also have side-effects will be abandoned in favour of so-called rapidly metabolized corticoids (Tixocortol pivalate, beclomethasone, budenoside and fluticasone) by the oral route and in enemas and foams. As antimicrobial treatment ciprofloxacine is used combined with metronidazole. As to immunosuppressive drugs azathioprine, 6-mercaptopurine, cyclosporin A, cyclophosphamide and methotrexate are tested. A hope for the future is so-called biological treatment (anticytokines, monoclonal antibodies against cytokines, against CD4+ TNF, interleukines IL-10 and 11, immunoglobulin; plasmapheresis is also tested). Treatment must be individual and surgery as late as possible, only in case of complications, and should be very sparing, stenoses should be treated by plastic operations of strictures.
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PMID:[Treatment of Crohn's disease]. 1059 70

CD4+ T-lymphocytes have a central role in the pathogenesis of Crohn's disease. The activation and proliferation of T-lymphocytes following stimulation by antigen-presenting cells is controlled by regulatory cytokines (i.e. IL-10) and by induction of programmed cell death. Tissue damage as a result of T-lymphocyte-mediated inflammation is mediated by pro-inflammatory cytokines, including TNF-alpha. Novel immunodulatory strategies in Crohn's disease are based on these principles, and it has been demonstrated that neutralization of TNF-alpha by administration monoclonal antibodies as well as administration of recombinant human IL-10 have therapeutic activity in Crohn's disease. The current status of these new therapies as well as future developments are discussed.
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PMID:Immunotherapy of Crohn's disease. 1063 71

Inflammatory bowel diseases (IBD: Crohn's disease, ulcerative colitis) are chronic inflammatory and frequently relapsing diseases of the gut that ultimately lead to destruction of the intestinal tissue. Recent evidence suggests that a pathologic activation of the mucosal immune system in response to antigens is a key factor in the pathogenesis of IBD. Furthermore, changes in cell migration and cytokine production appear to contribute to the perpetuation of IBD and the postoperative recurrence of Crohn's disease. Based on recent advances in our understanding of the pathogenesis of IBD, several new therapeutic strategies are currently being tested in clinical practice, including recombinant anti-inflammatory cytokines (IFN-alpha, IL-10, IL-11) and inhibitors of cell adhesion molecules (ICAM), proinflammatory cytokines (TNF, IL-12) and their receptors (TNF, IL-6R).
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PMID:[Immunopathogenesis of inflammatory bowel diseases]. 1066 99

Inflammatory bowel diseases are considered to be related to dysregulation of pro- and anti-inflammatory cytokines in the intestinal wall. We investigated the levels of TNFalpha, IFNgamma, and IL-10 mRNA expression in intestinal tissues resected from the patients with Crohn disease (CD) (n=29), ulcerative colitis (UC) (n=8), and controls (n=8) using reverse transcription-polymerase chain reaction (RT-PCR). In addition, we examined the relationship between the expression of these cytokine mRNA and their clinical conditions using CD activity index (CDAI) and Nutritional Surgical Risk Index (NSRI). Compared with controls, tissues in CD showed high levels of TNFalpha and IFNgamma mRNA expression both in inflamed and non-inflamed tissues, and showed high levels of IL-10 mRNA expression in inflamed tissues. In UC, high levels of IL-10 mRNA expression were detected both in inflamed and non-inflamed UC tissues, while those of TNFalpha and IFNgamma were not. In 80% of CD tissues (n=23), levels of IL-10 and TNFalpha expression were interrelated. While the remaining tissues (n=6) showed low levels of IL-10 expression despite high levels of TNFalpha expression in inflamed CD tissues, and 4 of these 6 patients had high CDAI and low NSRI. Furthermore, in low nutritional CD patients (NSRI <40, n=13), the levels of IL-10 mRNA to inhibit pro-inflammatory cytokines were poorer than in good nutritional patients (NSRI >/=40, n=16). These findings suggest the overexpressions of TNFalpha and IFNgamma in CD, and less producibility of IL-10 against these cytokine might lead to development of severe CD.
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PMID:Interleukin-10 expression in intestine of Crohn disease. 1071 56

Inflammatory bowel diseases (IBD) are characterized by a sustained inflammatory cascade that gives rise to the release of mediators capable of degrading and modifying bowel wall structure. Our aims were (i) to measure the production of matrix metalloproteinase-3 (MMP-3), and its tissue inhibitor, tissue inhibitor of metalloproteinase-1 (TIMP-1), by inflamed and uninflamed colonic mucosa in IBD, and (ii) to correlate their production with that of proinflammatory cytokines and the anti-inflammatory cytokine, IL-10. Thirty-eight patients with IBD, including 25 with Crohn's disease and 13 with ulcerative colitis, were included. Ten controls were also studied. Biopsies were taken from inflamed and uninflamed regions and inflammation was graded both macroscopically and histologically. Organ cultures were performed for 18 h. Tumour necrosis factor-alpha (TNF-alpha), IL-6, IL-1beta, IL-10, MMP-3 and TIMP-1 concentrations were measured using specific immunoassays. The production of both MMP-3 and the TIMP-1 were either undetectable or below the sensitivity of our immunoassay in the vast majority of uninflamed samples either from controls or from those with Crohn's disease or ulcerative colitis. In inflamed mucosa, the production of these mediators increased significantly both in Crohn's disease (P < 0.01 and 0.001, respectively) and ulcerative colitis (P < 0.001 and 0.001, respectively). Mediator production in both cases was significantly correlated with the production of proinflammatory cytokines and IL-10, as well as with the degree of macroscopic and microscopic inflammation. Inflamed mucosa of both Crohn's disease and ulcerative colitis show increased production of both MMP-3 and its tissue inhibitor, which correlates very well with production of IL-1beta, IL-6, TNF-alpha and IL-10.
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PMID:Increased production of matrix metalloproteinase-3 and tissue inhibitor of metalloproteinase-1 by inflamed mucosa in inflammatory bowel disease. 1079 71

Inflammatory bowel disease (IBD) comprises the two disorders ulcerative colitis (UC) and Crohn's disease (CD). Although the etiology is still unclear, initiation and aggravation of the inflammatory processes seem to be due to a massive local mucosal immune response. An increased number of greatly activated macrophages seems to contribute to the onset of IBD by expressing upregulated costimulatory molecules (e.g., CD80/CD86) and a cytokine profile favouring a type I proinflammatory response. The release of interleukin 2 (IL-2) and Interferon-gamma (IFN-gamma) by naive T lymphocytes predominantly stimulates cytotoxic T lymphocytes, macrophages, and natural killer (NK) cells and increases the antigen-presenting potential of all these cell types. Opposite this proinflammatory immune reaction a compensatory type II antiinflammatory response has been suggested in the inflamed mucosa, involving mainly interleukin 4 and interleukin 10. Both cytokines are able to down-regulate inflammatory mediators including tumor necrosis factor-alpha (TNF-alpha) and interleukin 1 and favor a humoral immune response. The main goal of this clinical trial is the local liposome-mediated gene transfer of these two antiinflammatory cytokines, interleukin 4 and interleukin 10, in patients with severe IBD of the rectum. This local administration of antiinflammatory cytokines will avoid toxic systemic side effects, prevents blocking of the beneficial effects of proinflammatory cytokines, e.g., TNF-alpha in other tissue compartments and increases the local concentration of interleukin 4 and interleukin 10 over a prolonged period of time. The combined effects of IL-4 and IL-10 have been shown to shift the Th1/Th2 cell activation in favor of a Th2 immune response which seems to be essential for fighting against the inflammation and ultimative healing.
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PMID:Transfer of interleukin-4 and interleukin-10 in patients with severe inflammatory bowel disease of the rectum. 1095 7

Crohn's disease is a chronic disease characterized by oxidant-induced tissue injury and increased intestinal permeability. A consequence of oxidative damage is the accumulation of DNA strand breaks and activation of poly(ADP-ribose) polymerase (PARP), which subsequently catalyzes ADP-ribosylation of target proteins. In this study, we assessed the role of PARP in the colitis seen in interleukin (IL)-10 gene-deficient mice. IL-10 gene-deficient mice demonstrated significant alterations in colonic cellular energy status in conjunction with increased permeability, proinflammatory cytokine release, and nitrosative stress. After 14 days of treatment with the PARP inhibitor 3-aminobenzamide, IL-10 gene-deficient mice demonstrated normalized colonic permeability; reduced tumor necrosis factor-alpha and interferon-gamma secretion, inducible nitric oxide synthase expression, and nitrotyrosine levels; and significantly attenuated inflammation. Time course studies demonstrated that 3-aminobenzamide rapidly altered cellular metabolic activity and decreased cellular lactate levels. This was associated with normalization of colonic permeability and followed by a downregulation of proinflammatory cytokine release. Our data demonstrate that inhibition of PARP activity results in a marked improvement of colonic inflammatory disease and a normalization of cellular metabolic function and intestinal permeability.
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PMID:Inhibition of poly(ADP-ribose) polymerase attenuates inflammation in a model of chronic colitis. 1096 Mar 65

IL-18 is a cytokine with potent IFN-gamma inducing activities as well as an important mediator of Th1 polarized immune responses. In this study we demonstrated that IL-18 induces the concentration-dependent production of the proinflammatory mediators IFN-gamma, IL-6, and GM-CSF, but not the anti-inflammatory cytokine, IL-10 from peripheral blood lymphocytes in the presence of mitogen. Three neutralizing IL-18 monoclonal antibodies (MAbs) were investigated, one of which (2C10) inhibited IL-18 bioactivity with an IC50 of 0.1 nM and had a K(D) of 3.9 x 10(-11) M. A NOD/SCID mouse model engrafted with human peripheral blood lymphocytes was developed to test the in vivo efficacy of this MAb. The IFN-gamma production induced by LPS administration was inhibited approximately 90% by prior dosing of MAb 2C10. The therapeutic utility of a high-affinity IL-18 MAb may be of benefit in Th1-driven autoimmune diseases such as rheumatoid arthritis and Crohn's Disease, where elevated levels of IL-18 have been observed.
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PMID:Characterization of the in vitro and in vivo activity of monoclonal antibodies to human IL-18. 1112 25

Trinitrobenzene sulfonic acid (TNBS)-induced colitis is an IL-12-driven, Th1 T cell-mediated colitis that resembles human Crohn's disease. In the present study, we showed initially that the oral administration of recombinant subunit B of cholera toxin (rCT-B) at the time of TNBS-induced colitis by intrarectal TNBS instillation inhibits the development of colitis or, at later time when TNBS-induced colitis is well established, brings about resolution of the colitis. Dose-response studies showed that a majority of mice (68%) treated with rCT-B at a dose of 100 microg (times four daily doses) exhibited complete inhibition of the development of colitis, whereas a minority (30%) treated with rCT-B at a dose of 10 microg (times four daily doses) exhibited complete inhibition; in both cases, however, the remaining mice exhibited some reduction in the severity of inflammation. In further studies, we showed that rCT-B administration is accompanied by prevention/reversal of increased IFN-gamma secretion (the hallmark of a Th1 response) without at the same time causing an increase in IL-4 secretion. This decreased IFN-gamma secretion was not associated with the up-regulation of the secretion of counterregulatory cytokines (IL-10 or TGF-beta), but was associated with a marked inhibition of IL-12 secretion, i.e., the secretion of the cytokine driving the Th1 response. Finally, we showed that rCT-B administration results in increased apoptosis of lamina propria cells, an effect previously shown to be indicative of IL-12 deprivation. From these studies, rCT-B emerges as a powerful inhibitor of Th1 T cell-driven inflammation that can conceivably be applied to the treatment of Crohn's disease.
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PMID:Oral administration of recombinant cholera toxin subunit B inhibits IL-12-mediated murine experimental (trinitrobenzene sulfonic acid) colitis. 1120 12


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