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Differentiation between intestinal tuberculosis (ITB) and Crohn's disease (CD) is challenging in geographical regions where both these diseases are prevalent. There is a need of biomarkers for differentiation between these two disorders. Colonic biopsies from inflamed mucosa of treatment-naive patients with ITB, CD and controls were used for analysis. Protein extracted from biopsies was digested with trypsin and resulting peptides were labeled with iTRAQ reagents. The peptides were subsequently analyzed using LC-MS/MS for identification and quantification. Gene ontology annotation for proteins was analyzed in PANTHER. Validation experiments were done for six differentially expressed proteins using immunohistochemistry. 533 proteins were identified and 241 proteins were quantified from 5 sets of iTRAQ experiments. While 63 were differentially expressed in colonic mucosa of patients with CD and ITB in at least one set of iTRAQ experiment, 11 proteins were differentially expressed in more than one set of experiments. Six proteins used for validation using immunohistochemistry in a larger cohort of patients; none of them however was differentially expressed in patients with ITB and CD. There are differentially expressed proteins in tissue proteome of CD and ITB. Further experiments are required using a larger cohort of homogeneous tissue samples.

Abnormalities of transmembrane and cytoplasmic proteins of tight junctions (TJ) have been implicated in pathogenesis of both celiac (CeD) and Crohn's diseases (CD). Since disease pathogenesis in CeD and CD are different, we planned to study if there is any differential expression pattern of TJ marker proteins and ultrastructural changes, respectively, in duodenal villi vs crypts. Endoscopic duodenal biopsies from treatment naïve patients with CeD (n = 24), active CD (n = 28), and functional dyspepsia (as controls, n = 15), both at baseline and 6 months after treatment, were subjected to light microscopic analysis (modified Marsh grading); immune-histochemical staining and Western blot analysis to see the expression of key TJ proteins [trans-membrane proteins (claudin-2, claudin-3, claudin-4, occludin, and JAM) and cytoplasmic protein (ZO-1)]. Transmission electron microscopy and image analysis of the TJs were also performed. There was significant overexpression of claudin-2 (pore-forming) and occludin (protein maintaining cell polarity) with under-expression of claudin-3 and claudin-4 (pore-sealing proteins) in treatment naïve CeD and active CD with simultaneous alteration in ultrastructure of TJs such as loss of penta-laminar structure and TJ dilatation. Normalization of some of these TJ proteins was noted 6 months after treatment. These changes were not disease specific and were not different in duodenal villi and crypts. Overexpression of pore-forming and under-expression of pore-sealing TJ proteins lead to dilatation of TJ. These changes are neither disease specific nor site specific and the end result of mucosal inflammation.

Background: Increased intestinal permeability (IP) has been implicated in the etiopathogenesis, disease activity and relapse of Crohn's disease (CD). Glutamine, the major fuel for the enterocytes, may improve IP., Aim: We evaluated the effect of oral glutamine on IP and intestinal morphology in patients with CD., Methods: In a randomized controlled trial, consecutive patients with CD in remission phase with an abnormal IP were randomized to a glutamine group (GG) or active control group (ACG) and were given oral glutamine or whey protein, respectively, as 0.5 g/kg ideal body weight/day for 2 months. IP was assessed by the lactulose mannitol excretion ratio (LMR) in urine, and morphometry was performed by computerized image analysis system., Results: Patients (age 34.5 ± 10.5 years; 20 males) were assigned to the GG (n = 15) or ACG (n = 15). Fourteen patients in each group completed the trial. The LMR [median (range)] in GG and ACG at 2 months was 0.029 (0.006-0.090) and 0.033 (0.009-0.077), respectively, with P = 0.6133. IP normalized in 8 (57.1%) patients in each group (P = 1.000). The villous crypt ratio (VCR) [mean (SD)] in GG and ACG at 2 months was 2.68 (1.02) and 2.49 (0.67), respectively, (P = 0.347). At the end of 2 months LMR improved significantly in GG from 0.071 (0.041-0.254) to 0.029 (0.006-0.090) (P = 0.0012) and in ACG from 0.067 (0.040-0.136) to 0.033 (0.009-0.077) (P = 0.0063). VCR improved in the GG from 2.33 (0.77) to 2.68 (1.02) (P = 0.001), and in ACG from 2.26 (0.57) to 2.49 (0.67) (P = 0.009)., Conclusions: Intestinal permeability and morphology improved significantly in both glutamine and ACG.

We intended to see the pattern of TJ protein expression along with ultrastructural changes in colonic biopsies from patients with Crohn's disease (CD), ulcerative colitis (UC), and tuberculosis (cTB). Colonic biopsies from 11 patients with active CD and ten patients each with active UC and untreated cTB were taken along with biopsies from six patients with irritable bowel syndrome as controls. These were evaluated for expression pattern of key TJ proteins which included claudin-2 as TJ pore-forming protein, claudin-4 as pore-sealing protein, ZO-1 as scaffold protein, and occludin as TJ protein related to cell migration and polarity. Claudin-2 expression was upregulated along the whole length of intercellular junction (ICJ) in biopsies from patients with active CD and UC in comparison to the biopsies from cTB patients and controls, where its expression was limited to the uppermost part of ICJ. There was reduced expression of ZO-1 in UC, CD, and cTB. On transmission electron microscopic examination, the pentalaminar structure of TJs was destroyed in patients with CD and UC but no significant change was seen in those with cTB and in controls. The expression of claudin-2 was distinctly different in active CD and UC in comparison to its expression pattern in patients with cTB and in controls. The redistribution of claudin-2 expression was in accordance with the TJ ultrastructural changes in patients with UC, CD, and cTB. Altered claudin-2 expression, along with destroyed TJs, may result in loss of selective permeability in patients with UC and CD.

Objectives: The clinical, endoscopic, and histological features of Crohn's disease (CD) and intestinal tuberculosis mimic each other so much that it becomes difficult to differentiate between them. The aim was to find out clinical, endoscopic, and histological predictor features for differentiation between CD and intestinal tuberculosis., Methods: We recruited 106 patients, 53 each with CD and intestinal tuberculosis, in this study. The clinical, histological, and endoscopic features were subjected to univariate, bivariate, and multivariate analyses. On the basis of regression coefficients of the final multivariate logistic model, a score to discriminate between CD and intestinal tuberculosis was devised. For the validation of the score, the same model was tested on 20 new patients, each with CD and intestinal tuberculosis., Results: On univariate analysis, although longer duration of disease, chronic diarrhea, blood in stool, perianal disease, extra-intestinal manifestations, involvement of left colon, skip lesions, aphthous ulcers, cobblestoning, longitudinal ulcers, focally enhanced colitis, and microgranulomas were significantly more common in CD, partial intestinal obstruction, constipation, presence of nodular lesions, higher number, and larger granulomas were significantly more common in intestinal tuberculosis. On multivariate analysis, blood in stool (odds ratio (OR) 0.1 (confidence interval (CI) 0.04-0.5)), weight loss (OR 9.8 (CI 2.2-43.9)), histologically focally enhanced colitis (OR 0.1 (CI 0.03-0.5)), and involvement of sigmoid colon (OR 0.07(0.01-0.3)) were independent predictors of intestinal tuberculosis. On the basis of regression coefficients of the final multivariate logistic model, a score that varied from 0.3 to 9.3 was devised. Higher score predicted more likelihood of intestinal tuberculosis. Once the cutoff was set at 5.1, then the sensitivity, specificity, and ability to correctly classify the two diseases were 83.0, 79.2, and 81.1%, respectively. Area under the curve for receiver-operating characteristic (ROC) to assess the ability of these features to discriminate between CD and intestinal tuberculosis was 0.9089. The area under ROC in the validation data set was 89.2% (95% CI 0.79-0.99). With a similar cutoff score of 5.1, sensitivity and specificity in the validation model were 90% (95% CI 66.9-98.2) and 60% (95% CI 36.4-80.0), respectively., Conclusions: Blood in stool, weight loss, focally enhanced colitis, and involvement of the sigmoid colon were the most important features in differentiating CD from intestinal tuberculosis.

Background/Aims: Classical M1 macrophage activation exhibits an inflammatory phenotype while alternative M2 macrophage activation exhibits an anti-inflammatory phenotype. We aimed to determine whether there are discriminant patterns of macrophage polarization in Crohn's disease (CD) and intestinal tuberculosis (iTB). Methods: Colonic mucosal biopsies from 29 patients with iTB, 50 with CD, and 19 controls were examined. Dual colored immunohistochemistry was performed for iNOS/CD68 (an M1ϕ marker) and CD163/CD68 (an M2ϕ marker), and the ratio of M1ϕ to M2ϕ was assessed. To establish the innate nature of macrophage polarization, we analyzed the extent of mitochondrial depolarization, a key marker of inflammatory responses, in monocyte-derived macrophages obtained from CD and iTB patients, following interferon-γ treatment. Results: M1ϕ polarization was more prominent in CD biopsies (P =0.002) than in iTB (P =0.2) and control biopsies. In granuloma-positive biopsies, including those in CD, M1ϕ predominance was significant (P =0.001). In iTB, the densities of M1ϕ did not differ between granuloma-positive and granuloma-negative biopsies (P =0.1). Interestingly, higher M1ϕ polarization in CD biopsies correlated with high inflammatory response exhibited by peripheral blood-derived monocytes from these patients. Conclusions: Proinflammatory M1ϕ polarization was more common in colonic mucosa of CD patients, especially in the presence of mucosal granulomas. Further characterization of the innate immune system could help in clarifying the pathology of iTB and CD. [ABSTRACT FROM AUTHOR]