Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P17931 (galectin-3)
 2,860 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Galectin-3, a member of beta-galactoside-binding lectins, is expressed and secreted by a variety of cell types including human intestinal epithelial cells. The presence of anti-galectin-3 antibody in the sera of patients was analyzed by immunoblotting using recombinant human galectin-3. A substantially higher percentage of sera from Crohn's disease patients contained anti-galectin-3 IgG autoantibodies than from patients with ulcerative colitis, primary biliary cirrhosis, or autoimmune hepatitis and of apparently healthy control volunteers. In Crohn's disease patients the titer of autoantibodies was high and interestingly correlated negatively with disease activity. To characterize and generate artificial epitopes (mimotopes), the anti-galectin-3 monoclonal antibodies A3A12 and B2C10 were used for biopannings of phage display nonapeptide libraries. These mimotopes interfered with the binding of autoantibodies to recombinant and native intestinal epithelial galectin-3. Our data may suggest that galectin-3 mimotopes could be used for the induction of IgG with desired specificity to regulate immune responses in Crohn's disease patients.
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PMID:Anti-Galectin-3 IgG autoantibodies in patients with Crohn's disease characterized by means of phage display peptide libraries. 1172 7

Recently we identified galectin-3 (gal-3), which is secreted by colonic epithelial cells (CEC), to be a strong activator of colonic lamina propria fibroblasts (CLPF). Modulation of CLPF function may play a role during stricture and fistula formation in inflammatory bowel disease (IBD). Therefore, we investigated further the expression of gal-3 and effects on CLPF. The aim of this study is to perform a direct comparison of gal-3 between tissue from healthy controls and from patients with either Crohn's disease (CD) or ulcerative colitis (UC). CEC, CLPF and intestinal macrophages (IMAC) were isolated from control and IBD colonic tissue. Interleukin-8 secretion as a readout of CLPF activation was quantified by enzyme-linked immunosorbent assay. Gal-3 in cell cultures and tissue samples was evaluated by Western blot, immunofluorescence and immunohistochemistry. CLPF-migration was assayed in the 48-well modified Boyden chamber. Gal-3 expression was found in all segments of the colon. In the terminal ileum, less gal-3 was found compared with the colon. Immunohistochemistry and immunofluorescence revealed a homogenous distribution of gal-3 in CEC and IMAC of control mucosa and UC. However, significantly less gal-3 was found in IMAC from CD patients. In CD fistulae and stenoses, gal-3 expression was reduced significantly and barely detectable. In co-incubation studies lactose reduced significantly the CLPF-stimulatory potential of gal-3, indicating that the C-terminal domain of gal-3 is responsible for CLPF activation. Gal-3 stimulated CLPF migration in CLPF derived from fistulae. In conclusion, gal-3 expression is down-regulated in CD-fistulae and stenoses as well as in IMAC in CD patients. Gal-3 induces migration of CLPF derived from fistulae. Its role for stricture and fistula formation warrants further investigation.
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PMID:Regulation of galectin-3 function in mucosal fibroblasts: potential role in mucosal inflammation. 1833 93

Similar changes in glycosylation occur in the colonic epithelium in inflammatory conditions such as ulcerative colitis and Crohn's disease and also in colon cancer and precancerous adenomatous polyps. They include reduced length of O-glycans, reduced sulfation, increased sialylation and increased expression of oncofetal carbohydrate antigens, such as sialyl-Tn (sialylalpha2-6GalNAc), and the TF antigen (Thomsen-Friedenreich antigen) Galbeta1-3GalNAcalpha-Ser/Thr. The changes affect cell surface as well as secreted glycoproteins and mediate altered interactions between the epithelium and lectins of dietary, microbial or human origin. Different TF-binding lectins cause diverse effects on epithelial cells, reflecting subtle differences in binding specificities e.g. for sialylated TF; some of these interactions, such as with the TF-binding peanut lectin that resists digestion, may be biologically significant. Increased TF expression by cancer cells also allows interaction with the human galactose-binding lectin, galectin-3. This lectin has increased concentration in the sera of patients with metastatic cancer and binds TF on cancer cell surface MUC1 (mucin 1), causing clustering of MUC1 and revealing underlying adhesion molecules which promote adhesion to endothelium. This is likely to be an important mechanism in cancer metastasis and represents a valid therapeutic target. Tools are now available to allow fast and accurate elucidation of glycosylation changes in epithelial disease, characterization of their potential lectin ligands, whether dietary, microbial or human, and determination of the functional significance of their interactions. This should prove a very fruitful area for future research with relevance to infectious, inflammatory and cancerous diseases of the epithelia.
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PMID:Lectin-epithelial interactions in the human colon. 1902 80

Galectins are lectins involved in physiological processes such as cell proliferation, apoptosis and migration, immune responses, inflammation, signalling, and angiogenesis. This study assessed the serum levels of galectin-3 (Gal-3) and galectin-3 (Gal-9) and galectin 3 binding protein (Gal-3BP), and evaluated their associations with the clinical characteristics and levels of inflammatory markers in patients with inflammatory bowel disease (IBD). A total of 48 patients with ulcerative colitis (UC), 77 with Crohn's disease (CD), and 30 healthy volunteers participated in the study. Complete blood counts, C-reactive protein, fibrinogen, albumin, glucose, creatinine, Gal-3, Gal-9, and Gal-3BP were measured. The median Gal-3 and Gal-9 levels did not differ between patients and controls. The median level of Gal-3BP was significantly higher in patients with CD than in controls (8084.6 (5637.8 - 11494.4) ng/ml versus 5962.2 (5280.15 - 7247.92) ng/ml, P = 0.02). No significant differences in Gal-3, Gal-9, and Gal-3BP between active and inactive CD and UC subgroups were found. The median Gal-3BP was higher in subgroups with active CD than in controls (8175.9 (5736.4 - 12871.62) ng/ml versus 5962.2 (5280.15 - 7247.92) ng/ml, P = 0.004). Our results showed that serum Gal-3 and Gal-9 should not be considered biomarkers of IBD. Despite not being a specific marker for CD, serum Gal-3BP might be used as an adjuvant biomarker for disease activity. However, further studies using a larger cohort are required to confirm its clinical usefulness.
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PMID:Serum galectin 3, galectin 9 and galectin 3-binding proteins in patients with active and inactive inflammatory bowel disease. 3101 24

The inflammatory bowel diseases (IBD), which include mainly Crohn's disease (CD) and ulcerative colitis (UC), are common chronic inflammatory conditions of the digestive system. The diagnosis of IBD relies on the use of a combination of factors including symptoms, endoscopy and levels of serum proteins such as C-reactive protein (CRP) or faecal calprotectin. Currently there is no single reliable biomarker to determine IBD. Galectins are a family of galactoside-binding proteins that are commonly altered in the circulation of disease conditions such as cancer and inflammation. This study investigated serum galectin levels as possible biomarkers in determining IBD and IBD disease activity. Levels of galectins-1, -2, -3, -4, -7 and -8 were analysed in 208 samples from ambulant IBD patients (97 CD, 71 UC) patients and 40 from healthy people. Disease activity was assessed using Harvey-Bradshaw Index for CD and simple clinical colitis activity index for UC. The relationship of each galectin in determining IBD and IBD disease activity were analysed and compared with current IBD biomarker CRP. It was found that serum level of galectin-1 and -3, but not galectins-2, -4, -7 and -8, were significantly higher in IBD patients than in healthy people. At cut-off of 4.1ng/ml, galectin-1 differentiated IBD from healthy controls with 71% sensitivity and 87% specificity. At cut-off of 38.5ng/ml, galectin-3 separated IBD from healthy controls with 53% sensitivity and 87% specificity. None of the galectins however were able to distinguish active disease from remission in UC or CD. Thus, levels of galectins-1 and -3 are significantly elevated in both UC and CD patients compared to healthy people. Although the increased galectin levels are not able to separate active and inactive UC and CD, they may have the potential to be developed as useful biomarkers for IBD diagnosis either alone or in combination with other biomarkers.
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PMID:Serum galectins as potential biomarkers of inflammatory bowel diseases. 3192 64