Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0009319 (colitis)
 19,384 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Colonic ischemia (CI) is a rare complication of high-dose interleukin-2 (IL-2) immunotherapy. This complication occurred in three of 141 patients (2.1%) with metastatic cancer treated with high-dose IL-2 therapy; CI only developed in patients receiving interferon-alpha (IFN) with IL-2 (three of 21, 14%) compared with none of 120 in those patients receiving IL-2 alone (P equals 0.0009). Severe diarrhea (greater than or equal to 7 bowel movements/day) also was significantly more common in patients receiving IFN with IL-2 (six of 21, 29%) than in those receiving IL-2 alone (three of 120, 2.5%, P equals 0.001) and preceded the clinical diagnosis of CI in all three patients. Three of nine patients with severe diarrhea had CI. Hematochezia occurred in four patients, all of whom received IFN with IL-2; three had CI, and the other patient had nonspecific colitis. Differences in vasopressor use did not explain the increased risk of CI in patients receiving IFN; those receiving IFN with IL-2 required phenylephrine less often than patients receiving IL-2 alone (P equals 0.01). The administration of lymphokine-activated killer (LAK) cells had no significant effect on the incidence of CI, severe diarrhea, peritonitis, or vasopressor use; two of three patients with CI, however, had their ischemic episode within 24 hours after the last of three LAK cell infusions. In conclusion, CI is an unusual complication of high-dose IL-2 and IFN immunotherapy. In patients receiving such combination therapy, severe diarrhea is a risk factor for the subsequent occurrence of CI.
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PMID:Colonic ischemia complicating immunotherapy with interleukin-2 and interferon-alpha. 189 54

Mice deficient in interleukin-2 production (IL-2null mice) develop colonic inflammation closely resembling ulcerative colitis in humans. Although this disease is marked by substantial infiltration of the colon by CD8+ and CD4+ T lymphocytes, no function has yet been assigned to these T cell subsets in the development of colitis in the IL-2null mouse. For the present study, we investigated the involvement of T lymphocytes in the onset of colitis in IL-2null mice, and examined the possible role played by cytotoxic T cells. Both lamina propria lymphocytes (LPL) and intraepithelial lymphocytes (IEL) of the colon of IL-2null mice were potently cytotoxic ex vivo in short-term redirected cytotoxic lymphocyte (CTL) assays. In contrast, colonic T cells of wild-type animals showed little or no constitutive cytotoxic T cell activity. Colonic CTL were detectable prior to the appearance of disease in IL-2null animals and CTL activity was confined to the TcR alpha beta, rather than to the TcR gamma delta IEL subset. IL-2null animals crossed with major histocompatibility complex class I-deficient mice [IL-2null x beta 2 microglobulin (beta 2mnull) mice] also developed colitis, which appeared even earlier than in most IL-2null mice. These findings suggest that neither CD8+ IEL nor LPL were causal in the onset of colitis in IL-2null animals. In IL-2null x beta 2mnull mice, an ulcerative colitis-like disease was evident from histological studies and immunohistological staining which showed very large numbers of CD4+ lymphocytes within the intestinal mucosa. Significant ex vivo killing by CD4+ T cells was observed in IL-2null x beta 2null animals, although this required an extended incubation time compared to colonic CD8+ T cells. Peripheral as well as colonic CD4+ T cells in IL-2null and IL-2null x beta 2mnull animals, were activated as judged by their cell surface phenotype (CD45RBlo, L-selectinlo and CD69+). In light of these findings, we propose that infiltrating CD4+, but not CD8+ T cells are central to the inflammation observed in the intestinal mucosa in IL-2null colitis.
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PMID:Evidence that CD4+, but not CD8+ T cells are responsible for murine interleukin-2-deficient colitis. 758 35

We review clinical experience with the immunosuppressive drugs 6-mercaptopurine (6-MP) and azathioprine, cyclosporine, and methotrexate in the management of patients with Crohn's disease. 6-MP and azathioprine are closely related structurally. Their exact mechanism of action is unknown, but both cause immunosuppression by interfering with nucleic acid metabolism in the immunological sequence that follows antigenic stimulation. 6-MP and azathioprine have proved most useful for two indications: reducing steroid requirements and healing fistulas. Among patients who are dependent on steroids for control of active inflammatory Crohn's disease, approximately 50% can be completely weaned from prednisone, and an additional 25% can tolerate a substantial dose reduction when treated with 6-MP or azathioprine. Likewise, 6-MP is effective in closing fistulas in approximately one third of patients and in reducing fistula drainage in an additional one third. However, the onset of action is slow and the results may be dose dependent. Cyclosporine, a selective immunosuppressant drug, inhibits T lymphocytes by inhibiting expression of interleukin-2 and its receptors. Its principal usefulness may be in patients with disabling fistulas or active steroid-refractory colitis who cannot tolerate the several months required for a remission induced by 6-MP or azathioprine. Methotrexate, a dihydrofolate reductase inhibitor, has antimetabolite and antiinflammatory properties. Methotrexate is only slightly, if at all, faster acting than 6-MP or azathioprine. Its principal usefulness may therefore be in cases when these other drugs have not been tolerated or are ineffective.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Immunosuppressive drugs in Crohn's disease. 798 22

Mice deficient for the G protein subunit Gi2 alpha were obtained by gene targeting. They displayed a growth retardation that was apparent at 6 weeks of age. They subsequently developed diffuse colitis with clinical and histopathological features closely resembling those of ulcerative colitis in humans. Seven of 20 Gi2 alpha-deficient mice with colitis also developed adenocarcinomas of the colon. Gi2 alpha-deficient thymocytes displayed two- to fourfold increases in mature CD4+8- and CD4-8+ phenotypes, an approximately threefold increase in high-intensity CD3 staining and enhanced proliferative responses to T-cell receptor stimuli. Stimulation of Gi 2 alpha-deficient peripheral T cells induced a hyperresponsive profile of interleukin-2, tumour necrosis factor, and interferon-gamma production, which may reflect a heightened response of primed cells or a defective negative regulation. We suggest that Gi 2 alpha-deficient mice may represent a useful animal model for dissecting the pathomechanisms of inflammatory bowel disease and also for the development of novel therapeutic strategies.
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PMID:Gi2 alpha protein deficiency: a model of inflammatory bowel disease. 861 81

A large body of clinical experience on the adverse consequences of cytokine administration has accumulated since the last decade. Side-effects reported after the therapeutic use of cytokines has provided evidence that activation of the immune response may sometimes have deleterious consequences. Several effects appeared as a direct consequence of the immune activation induced by cytokines, e.g. flu-like reactions, vascular leak syndrome. Cytokine-induced exacerbation of underlying diseases or immune dysregulation were other complications of growing concern. Interferon-alpha (IFN-alpha) treatment has now been clearly linked with the exacerbation or the occurrence of several types of autoantibodies or autoimmune diseases (thyroiditis, systemic lupus erythematosus, hematologic disorders, insulin-dependent diabetes mellitus) or diseases involving altered cell-mediated immune functions (inflammatory dermatologic diseases, nephritis, pneumonitis, colitis). By contrast immunological side-effects of IFN-beta and IFN-gamma have been seldom reported. However, the extent of clinical experience with both of these cytokines is still very limited. Interleukin-2 (IL-2) has also been implicated in various conditions that may involve immunopathological processes (thyroid disorders, rheumatoid arthritis, dermatological diseases, interstitial nephritis). Growth factors have been more specifically linked with the development or the exacerbation of dermatological inflammatory diseases through neutrophils, monocytes/macrophages or eosinophils activation (e.g. cutaneous vasculitis and generalized cutaneous eruption, Sweet's syndrome, bullous eruption, psoriasis). Exacerbation of autoimmune thyroiditis was described with granulocyte-macrophage colony-stimulating factor (GM-CSF) only. The immunogenicity of cytokines is also of great relevance and the occurrence of antibodies binding IFN-alpha and IFN-beta, IL2 and GM-CSF have been reported. While the clinical significance of non-neutralizing antibodies is not clearly established, an absence of response or reversal of clinical efficacy has been described in patients developing neutralizing antibodies. Finally, several isolated reports have recently suggested that IFN-alpha treatment may be associated with several immunosuppressive effects while IL-2 is clinically associated with an increased incidence of infectious complications.
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PMID:Immune-mediated side-effects of cytokines in humans. 863 83

Mice with null mutations in cytokine or T cell receptor (TCR) genes develop intestinal inflammation. In the case of interleukin-2-/- and interleukin-10-/- mice it has been demonstrated that normal intestinal bacterial flora can cause gut pathology. TCR-alpha-/- mice not only develop colitis but also produce a strong antibody response to self-antigens, such as double-stranded DNA. It is therefore important to establish whether the intestinal inflammation develops spontaneously or is induced by luminal antigens. To address this issue, a germ-free colony of TCR-alpha-/- mice was derived and compared with TCR-alpha-/- mice kept in conventional specific-pathogen-free conditions. Although specific-pathogen-free animals developed colitis with a high level of penetrance, there was no evidence of intestinal pathology in germ-free animals. Furthermore, intestinal inflammation was not seen in TCR-alpha-/- mice colonized with a limited bacterial flora consisting of Lactobacillus plantarum, Streptococcus faecalis, S. faecium, and/or Escherichia coli. We conclude that intestinal inflammation in TCR-alpha-/- mice does not occur spontaneously nor does it result from the presence of bacteria, per se, but rather it is initiated by a specific organism or group of organisms normally present in the gut flora that have yet to be identified.
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PMID:T cell receptor-alpha beta-deficient mice fail to develop colitis in the absence of a microbial environment. 900 26

One of the major advances in the understanding of inflammatory bowel disease has been the observation that mice with immunoregulatory defects, such as interleukin-2 knockout (IL-2 -/-) mice, develop spontaneous gut inflammation. Here we have characterized the immune response in the ileum, caecum and colon of these mice before and after the onset of colitis by examining the cellular infiltrate, the cytokines produced by these cells and the mucosal vascular addressin MAdCAM-1. IL-2 -/- mice developed colitis after 35 days of age and before this the mice were apparently healthy. IL-2 -/- mice aged over 35 days with colitis had large numbers of CD4+, CD8+, alpha beta T-cell receptor (TCR)+ and gamma delta TCR+ T cells, macrophages, dendritic cells and MAdCAM-1+ endothelial cells in the caecum and colon. This was associated with an increase in the number of interferon-gamma (IFN-gamma), IL-1 and tumour necrosis factor-alpha (TNF-alpha) transcripts and a decrease in IL-4 and IL-10 transcripts. Treatment of IL-2 -/- mice with cyclosporin A significantly delayed mortality. Interestingly, IL-2 -/- mice under 35 days, although healthy, did show some subtle immunological signs of preclinical disease. There was a significant increase in the number of macrophages and dendritic cells in the colonic lamina propria and increased mRNA for IL-1 and TNF-alpha. There were also increased numbers of MAdCAM-1+ endothelial cells, but IFN-gamma transcripts were not elevated. These results suggest that T-cell-mediated colitis in IL-2 -/- mice may be secondary to an initial non-specific inflammation.
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PMID:Characterization of the mucosal cell-mediated immune response in IL-2 knockout mice before and after the onset of colitis. 920 68

This review summarizes the present knowledge on melatonin in several areas on physiology and discusses various prospects of its clinical utilization. Ever increasing evidence indicates that melatonin has an immuno-hematopoietic role. In animal studies, melatonin provided protection against gram-negative septic shock, prevented stress-induced immunodepression, and restored immune function after a hemorrhagic shock. In human studies, melatonin amplified the antitumoral activity of interleukin-2. Melatonin has been proven as a powerful cytostatic drug in vitro as well as in vivo. In the human clinical field, melatonin appears to be a promising agent either as a diagnostic or prognostic marker of neoplastic diseases or as a compound used either alone or in combination with the standard cancer treatment. Utilization of melatonin for treatment of rhythm disorders, such as those manifested in jet lag, shift work or blindness, is one of the oldest and the most successful clinical application of this chemical. Low doses of melatonin applied in controlled-release preparation were very effective in improving the sleep latency, increasing the sleep efficiency and rising sleep quality scores in elderly, melatonin-deficient insomniacs. In the cardiovascular system, melatonin seems to regulate the tone of cerebral arteries; melatonin receptors in vascular beds appear to participate in the regulation of body temperature. Heat loss may be the principal mechanism in the initiation of sleepiness caused by melatonin. The role of melatonin in the development of migraine headaches is at present uncertain but more research could result in new ways of treatment. Melatonin is the major messenger of light-dependent periodicity, implicated in the seasonal reproduction of animals and pubertal development in humans. Multiple receptor sites detected in brain and gonadal tissues of birds and mammals of both sexes indicate that melatonin exerts a direct effect on the vertebrate reproductive organs. In a clinical study, melatonin has been used successfully as an effective female contraceptive with little side effects. Melatonin is one of the most powerful scavengers of free radicals. Because it easily penetrates the blood-brain barrier, this antioxidant may, in the future, be used for the treatment of Alzheimer's and Parkinson's diseases, stroke, nitric oxide, neurotoxicity and hyperbaric oxygen exposure. In the digestive tract, melatonin reduced the incidence and severity of gastric ulcers and prevented severe symptoms of colitis, such as mucosal lesions and diarrhea.
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PMID:Prospects of the clinical utilization of melatonin. 973 May 80

Mice deficient in both interleukin-2 and beta 2-microglobulin expression (Beta 2mullnull x IL-2null mice) develop an inflammatory disease of the colon resembling ulcerative colitis. To examine long-term complications of disease in these mice, a group of 34 Beta 2mnull x IL-2null mice was monitored for 6-12 months. Development of clinical disease was assessed by wasting, general appearance, and diarrhea. Further analysis included histologic examination of the distal colon for colitis, staining of CD4+ T cells for surface activation markers, and cytoplasmic staining of CD4+ T cells for IFN-gamma and TNF-alpha. These older Beta 2mnull x IL-2null mice had activated CD4+ T cells as assessed by surface markers on flow cytometry. Cytoplasmic staining revealed IFN-gamma production, but not TNF-alpha production by CD4+ T cells. The majority of these older Beta 2mnull x IL-2null mice continued to have colitis on histology. However, they lived much longer and had less wasting in comparison to IL-2null mice. At necropsy, 11 (32%) of 34 of the Beta 2mnull x IL-2null mice had tumors in the proximal half of the colon. Histologic examination confirmed these tumors to be adenocarcinomas. These mice may be useful as a model for studying carcinogenesis in chronic colitis.
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PMID:Development of colonic adenocarcinomas in a mouse model of ulcerative colitis. 974 Oct 21

Recent studies support nuclear factor-kappaB (NF-kappaB) as a critical transcription factor in inflammatory bowel disease. We examined NF-kappaB and its inhibitors, IkappaB-alpha and IkappaB-beta, in the colitis of interleukin-2 deficient (IL-2-/-) mice at the ages of 5, 10, and 15 weeks and compared them with those of age-matched wild-type mice. Colon levels of nuclear NF-kappaB and mRNA for NF-kappaB responsive cytokines interleukin-1beta and tumor necrosis factor-alpha were markedly increased in interleukin-2-/-mice. Colon interleukin-1beta protein levels were significantly elevated, consistent with increased interleukin-1beta mRNA, whereas tumor necrosis factor-alpha protein levels were either lower than those of the control group or did not differ. Protein levels of the immunomodulatory cytokine interleukin-10 were diminished. The NF-kappaB responsive IkappaB-alpha was also increased, mirroring NF-kappaB activation. In contrast, IkappaB-beta levels did not differ from those of wild-type mice in the 5- and 10-week groups and were only mildly increased in the 15-week group. Serum amyloid A, an acute phase protein that also is NF-kappaB-responsive, was dramatically elevated in the serum of interleukin-2-/- mice and correlated with the severity of the colitis. These data support a role for NF-kappaB in the pathogenesis of intestinal inflammation in interleukin-2-/- mice. The measurement of NF-kappaB in colon tissue samples may provide a sensitive means of assessing the state of activation of the mucosal immune response, and serum amyloid A appears to be a reliable biochemical marker of disease activity.
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PMID:Increased nuclear factor-kappaB activation in colitis of interleukin-2-deficient mice. 1052 Oct 84


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