Differential expression of pro-inflammatory cytokines and a pro-apoptotic protein in pelvic ileal pouches for ulcerative colitis and familial adenomatous polyposis

Incidence and Risk Factors of Cancer in the Anal Transitional Zone and Ileal Pouch following Surgery for Ulcerative Colitis and Familial Adenomatous Polyposis

Proctocolectomy with ileal pouch-anal anastomosis is the intervention of choice for ulcerative colitis and familial adenomatous polyposis requiring surgery. One of the long-term complications is pouch cancer, having a poor prognosis. The risk of high-grade dysplasia and cancer in the anal transitional zone and ileal pouch after 20 years is estimated to be 2 to 4.5% and 3 to 10% in ulcerative colitis and familial polyposis, respectively. The risk factors for ulcerative colitis are the presence of pre-operative dysplasia or cancer, disease duration > 10 years and severe villous atrophy. For familial polyposis, the risk factors are the number of pre-operative polyps > 1000, surgery with stapled anastomosis and the duration of follow-up. In the case of ulcerative colitis, a pouchoscopy should be performed annually if one of the following is present: dysplasia and cancer at surgery, primary sclerosing cholangitis, villous atrophy and active pouchitis (every 5 years without any of these factors). In the case of familial polyposis, endoscopy is recommended every year including chromoendoscopy. Even if anal transitional zone and ileal pouch cancers seldom occur following proctectomy for ulcerative colitis and familial adenomatous polyposis, the high mortality rate associated with this complication warrants endoscopic monitoring.

Immune Microenvironment: New Insight for Familial Adenomatous Polyposis

Currently, the main treatment for familial adenomatous polyposis (FAP) is surgery, however, surgery is far from ideal as there are many complications such as uncontrollable bowel movements, pouch inflammation, anastomotic stricture, and secondary fibroids. Therefore, it is necessary to further expand the understanding of FAP and develop new treatments for FAP. The immune microenvironment including immune cells and cytokines, plays an important role in FAP and the progression of FAP to adenocarcinoma, thus it may be a promising treatment for FAP. In the current review, we summarized the recent progress in the immune microenvironment of FAP.

Difference in the frequency of pouchitis between ulcerative colitis and familial adenomatous polyposis: is the explanation in peripouch fat?

AIM

Patients with ulcerative colitis (UC) have an unexplained higher incidence of pouchitis and a greater amount of peripouch fat compared with patients with familial adenomatous polyposis (FAP). The aims of this study were to compare the peripouch fat areas between patients with UC and patients with FAP, and to explore relationship between peripouch fat and pouchitis or chronic antibiotic-refractory pouchitis (CARP).

METHOD

Patients with an abdominal CT image from our prospectively maintained Pouch Database were included. Abdominal fat and peripouch fat were measured on CT images at different levels or planes. Comparisons of peripouch fat and CARP were performed before and after propensity score matching.

RESULTS

A total of 277 patients with UC and 40 patients with FAP were included. Compared with patients with FAP, patients with UC were found to have a higher incidence of pouchitis (58.5% vs 15.0%, P < 0.001) and CARP (24.5% vs 2.5%, P = 0.002) and a higher total peripouch fat area (P = 0.030) and mesenteric peripouch fat area (P = 0.022) at Level-3. Univariate and multivariate analyses showed that diagnosis (UC vs FAP) and peripouch fat areas at Level-3 and Level-5 were independent risk factors for CARP. With propensity score matching, 38 pairs of patients with UC and FAP were matched successfully. After matching, patients with UC were found to have higher total peripouch fat area and higher mesenteric peripouch fat area at Level-3, and a higher incidence of pouchitis (57.9% vs 13.2%, P < 0.001) and CARP (23.7% vs 2.6%, P = 0.007).

CONCLUSION

Our study demonstrates that patients with UC have more peripouch fat than those with FAP, which may explain the difference in the frequency of pouchitis and CARP between these groups of patients.

Ileal pouch of ulcerative colitis and familial adenomatous polyposis patients exhibit modulation of autophagy markers

Total retocolectomy with ileal pouch-anal anastomosis (IPAA) is the surgery of choice for patients with ulcerative colitis (UC) that are refractory to clinical treatment. Pouchitis is one of the most common complications after this procedure. Defects in autophagy have been reported in inflammatory bowel diseases. However, there are no studies on the IP. Therefore, we studied markers for autophagy in the IP mucosa of UC and FAP patients comparing them to controls with a normal distal ileum. Sixteen patients with IP in "J" shape, asymptomatic and with endoscopically normal IP were evaluated. The control group consisted of eight patients with normal colonoscopy. There was a significant decrease in the transcriptional levels of ATG5, MAP1LC3A and BAX in the FAP group. There was also a decrease in the protein level of Beclin-1 in the UC and FAP compared to the control group. Although the LC3II levels by immunoblot were higher in the UC group, LC3/p62 co-localization were lower in the immunofluorescence analysis in the UC and FAP compared to the control group. Corroborating these results, there was an increase of p62 by immunoblot in the UC group. These findings indicated a modulation of macroautophagy markers in the IP, which may explain the mucosa inflammation predisposition.

Tripterygium wilfordii polyglycosidium ameliorates pouchitis induced by dextran sulfate sodium in rats

BACKGROUND

The aim of this study was to investigate the therapeutic effects of Tripterygium wilfordii polyglycosidium (TWP) to rats with dextran sulfate sodium (DSS)-induced pouchitis and its possible mechanism.

METHODS

Sprague-Dawley rats underwent surgery of ileal pouch anal anastomosis (IPAA) and pouchitis was induced by DSS. Rats were randomly divided into no intervention (NI), normal saline (NS) and TWP groups. Rats were lavaged with normal saline (3ml/day in NS group) or TWP (12mg/kg/day in TWP group) for 7days. General conditions of animals and histopathological examinations were evaluated. Interleukin (IL)-1β, IL-6, IL-10, and tumor necrosis factor (TNF)-α mRNA expression was measured. Levels of occludin and Zo-1 proteins were measured by immunohistochemistry. In addition, ALT and AST were assessed.

RESULTS

TWP significantly attenuated the symptoms of pouchitis characterized by body weight loss, diarrhea, and bloody stool. Furthermore, TWP diminished histological damage compared with other groups. There was a significant reduction in levels of IL-1β, IL-6, and TNF-α, as well as an increase in IL-10 in the TWP group. The expression of tight junction proteins occludin and Zo-1 were increased in the TWP group. There were no statistical differences in serum ALT and AST among the three groups.

CONCLUSIONS

TWP significantly ameliorated pouchitis and inhibited the production of IL-1β, IL-6, and TNF-α as well as increased the levels of IL-10, occludin, and Zo-1 protein in rats. These findings suggest TWP might be a potential therapeutic agent for patients with pouchitis.

Therapeutic effects of triptolide via the inhibition of IL-1β expression in a mouse model of ulcerative colitis

The present study aimed to investigate the effect of triptolide (TL) on ulcerative colitis (UC) and explore the potential association between the therapeutic effects of TL and IL-1β expression using a 4,4-dimethyl-4-silapentane-1-sulfonic acid (DSS)-induced mouse model to simulate human UC. A total of 70 BALB/c female mice were randomly allocated into seven equal groups: Group A, blank control; group B, normal saline injection; group C, propylene glycol injection; group D (TL1), 0.2 mg/kg TL; group E (TL2), 0.4 mg/kg TL; group F (TL3), 0.6 mg/kg TL; and group G, dexamethasone injection. Mice activity, diet and stool characteristics were recorded daily. Mice were sacrificed by cervical dislocation on day 8, and disease activity indices, colon tissue histological scores and colonic histopathological scores were subsequently calculated. Serum levels of IL-1β were evaluated by enzyme-linked immunosorbent assay, and IL-1β expression levels were examined by reverse transcription-quantitative polymerase chain reaction with colonic mucosa specimen at the gene level and western blot analysis at the protein level. The IL-1β mRNA and protein expression levels were significantly elevated in the normal saline injection and propylene glycol injection groups compared with the blank control group and (P<0.01). In TL (TL2 and TL3)- and dexamethasone-treated mice, IL-1β expression levels were significantly decreased, as compared with the normal saline and propylene glycol injection groups (P<0.05). No significant difference was detected between TL (TL2 and TL3) and dexamethasone treatments. The results of the present study indicated that IL-1β expression was upregulated in the UC mouse model, which may be associated with the development and progression of UC. Furthermore, TL inhibited IL-1β expression, suggesting that TL may be a novel therapeutic target for the treatment of UC.

Dynamic evaluation of a mouse model of DSS induced ulcerative colitis

AIM: To develop an experimental mouse model of ulcerative colitis (UC) and to dynamically monitor the colonic injures, pathological changes, and contents of interleukin (IL)-1β, IL-18, and IL-33 in plasma and colonic mucosa to evaluate the model.

METHODS: Sixty-four C57BL/6 mice were randomly divided into either a normal group or a model group. The model group was fed 3% dextran sulfate sodium (DSS) solution for a week, followed by normal drinking water for another 3 wk. We then dynamically observed fecal condition, alterations of colon length and weight, pathological changes, colonic mucosa inflammation score and contents of IL-1β, IL-18, and IL-33 in plasma and colonic mucosa every week.

RESULTS: One week after modeling, the mice developed diarrhea, bloody stools, crouching, and huddled together. Pathological examination showed colon epithelial erosion, bleeding, multifocal ulcers and numerous inflammation cells infiltrating the mucosa and submucosa. Compared to the normal group, the colon weight was markedly increased (P < 0.05), the colon length was significantly shortened (P < 0.01), the colonic mucosa inflammation score was significantly increased (P < 0.01), and the contents of IL-1β, IL-18, and IL-33 in both plasma and mucosa were significantly elevated (P < 0.05, P < 0.01) in the model group. At the end of the second week, compared to the normal group, the model group had gradually decreased bleeding, a large number of inflammatory cells in the submucosa, increased colon weight (P < 0.01), shortened colon length (P < 0.01), increased colonic mucosa inflammation score (P < 0.01), and dramatically elevated contents of IL-1β and IL-18 in plasma and IL-18 in colonic mucosa (P < 0.05). At the third and fourth weeks, the mouse activity and fecal condition returned to normal, inflammation cells could be seen in colonic mucosa, muscle fiber was arranged disorderly; compared to normal group, colon weight was increased (P < 0.01), colon length was shortened (P < 0.01), but colonic mucosa inflammation score and the contents of IL-1β, IL-18, and IL-33 showed no significant changes in the model group (P > 0.05).

CONCLUSION: The dynamic changes in the mouse UC model show a shift from acute to chronic disease process, and this mouse model could be used for studying UC mechanism and treatment in the future.

Pouchitis: what every gastroenterologist needs to know

Pouchitis is the most common complication among patients with ulcerative colitis who have undergone restorative proctocolectomy with ileal pouch-anal anastomosis. Pouchitis is actually a spectrum of diseases that vary in etiology, pathogenesis, phenotype, and clinical course. Although initial acute episodes typically respond to antibiotic therapy, patients can become dependent on antibiotics or develop refractory disease. Many factors contribute to the course of refractory pouchitis, such as the use of nonsteroidal anti-inflammatory drugs, infection with Clostridium difficile, pouch ischemia, or concurrent immune-mediated disorders. Identification of these secondary factors can help direct therapy.

Gene expression profiles of ileal inflammatory bowel disease correlate with disease phenotype and advance understanding of its immunopathogenesis

BACKGROUND

Pouchitis may develop in patients with ulcerative colitis undergoing pouch surgery. We aimed to evaluate the de novo inflammation developing in the ileal pouch, hypothesizing that it may be similar to ileitis in Crohn's disease (CD).

METHODS

Patients with ulcerative colitis pouch were prospectively recruited, stratified according to disease behavior into normal pouch, chronic pouchitis, and Crohn's-like disease of the pouch groups, and compared with controls. Gene expression analysis was performed using microarrays, validated by real-time polymerase chain reaction. Gene ontology and clustering were evaluated using bioinformatic tools.

RESULTS

Sixty-six subjects were recruited. Although in ulcerative colitis ileum there were no significant gene expression alterations, patients with normal pouch had 168 significant alterations (fold change ≥ 2, corrected P ≤ 0.05). In chronic pouchitis and Crohn's-like disease of the pouch, 490 and 1152 alterations were detected, respectively. High degree of overlap in gene expression alterations between the pouch subgroups was demonstrated. The magnitude of change correlated with pouch disease behavior. Gene expression profiles were more reflective of disease behavior compared with inflammatory indices. CD ileitis had 358 alterations, with a 90% overlap with pouchitis. Gene ontology analyses revealed multiple biological processes associated with pouch inflammation, including response to chemical stimulus, small molecule metabolic and immune system processes, and specific infection-related pathways such as Staphylococcus aureus, leishmaniasis, and tuberculosis.

CONCLUSIONS

Gene alterations in pouch inflammation and CD overlap, suggesting that inflammatory bowel diseases is a spectrum, rather than distinct diseases. Pouchitis may serve as a model of CD. The novel pathways associated with inflammatory bowel diseases may decipher pathophysiology and suggest targets for intervention.

Cytomegalovirus infection of the ileoanal pouch: clinical characteristics and outcomes

BACKGROUND

Up to 30% of cases of pouchitis are felt to have a secondary cause. Cytomegalovirus (CMV) may represent a possible etiopathological agent. Here, we report our experience with CMV involvement of the pouch, including risk factors, clinical features, and pouch outcomes in patients with inflammatory bowel disease after proctocolectomy with ileal pouch-anal anastomosis.

METHODS

The pathology database at Mayo Clinic in Rochester was searched between January 1995 and October 2012 for patients with a tissue diagnosis of CMV of the pouch following ileal pouch-anal anastomosis.

RESULTS

Seven patients with CMV inclusions of the pouch were identified. The median age was 35 (range, 10-53) years, and the majority were female (71%). Five patients (71%) were on immunosuppressive medications including 4 who had undergone orthotopic liver transplantation for primary sclerosing cholangitis. The clinical presentation was similar among all patients: the majority had diarrhea (86%), fever (71%), and abdominal pain (57%). All had mucosal inflammation, with 71% having focal ulcerations in the pouch and 60% having inflammatory changes in the prepouch ileum. All patients improved with ganciclovir. None required pouch excision or had recurrent CMV infection. Three patients had recurrent nonspecific pouchitis.

CONCLUSIONS

A high index of suspicion is needed to diagnose CMV of the pouch. An increase in stool frequency and fever in patients on immune suppression or in those who have failed empiric antibiotics should prompt assessment for CMV infection. Antiviral therapy seems to be effective, and postinfection pouch outcomes seem favorable, particularly in those presenting with their first episode of pouchitis.

Recombinant human beta 2-defensin fusion proteins as a tool to investigate defensin structure and function in small human intestinal tissue samples

OBJECTIVE

Effects of immune cells on the beta 2 (β2)-defensin (HBD2) expression and its antibacterial activity in the intestinal mucosa of patients with inflammatory bowel diseases remains unclear. The small size of these proteins presents a major challenge in localizing antibacterial activities in human intestinal tissue. In this study, we evaluated the detection limits at mRNA and protein level by approaching HBD2 from small tissue samples.

METHODS

HT-29 colonic epithelial cells were incubated with proinflammatory cytokines before HBD2 mRNA was investigated by quantitative polymerase chain reaction. The HBD2 protein was assessed by Western blot analysis using HBD2 fused with enhanced green fluorescent protein (HBD2-EGFP). Purified HBD2 fused with the glutathione-S-transferase (GST-HBD2) was used to detect antibacterial activity in a densitometric assay.

RESULTS

Interleukin (IL)-1β induced HBD2 mRNA in HT-29 cells; however, tumor necrosis factor-α, IL-6 and IL-17 did not. The Western blot had a sensitivity of 1.5 pmol to detect recombinant HBD2, but did not detect HBD2 in either human intestinal or IL-1β-treated HT-29 cells. HBD2-EGFP was detected by HBD2-specific Western blot within cell lysates and culture supernants of transfected HT-29 and primary cells. In nanomolar ranges, GST-HBD2 reduced bacterial growth. The HBD2 bioactivity depended on solution conditions, but not on the size of the fusion partner.

CONCLUSION

The established fusion proteins provide excellent tools to evaluate expression patterns and antibacterial effects of HBD2 in human intestinal tissue samples.

Etiology of pouchitis

Restorative proctocolectomy with ileal-pouch anal anastomosis (RPC) is the operation of choice for ulcerative colitis (UC) patients requiring surgery. It is also used for patients with familial adenomatous polyposis (FAP). Pouchitis accounts for 10% of pouch failures. It is an idiopathic inflammatory condition that may occur in up to 50% of patients after RPC for UC. It is rarely seen in FAP patients after RPC. The etiology of pouchitis remains unclear. An overlap with UC is suggested by the frequency with which pouchitis affects patients with UC compared with FAP patients. There is significant clinical evidence implicating bacteria in the pathogenesis of pouchitis. Studies using culture and molecular methods demonstrate a dysbiosis of the pouch microbiota in pouchitis. Risk factors, genetic associations, and serological markers of pouchitis suggest that the interactions between the host immune responses and the pouch microbiota underlie the etiology of this idiopathic inflammatory condition. Here we present a detailed review of the data focusing on the pouch microbiota and the immune responses that support this hypothesis. We also discuss the contribution of luminal metabolic factors and the epithelial membrane in the etiology of this inflammatory process. The ileoanal pouch offers a unique opportunity to study the inter-relationships between the gut microbiota and host immune responses from before the onset of disease. For this reason the study of pouchitis could serve as a human model that significantly enhances our understanding of inflammatory bowel diseases in general.

Acute and chronic pouchitis--pathogenesis, diagnosis and treatment

Restorative proctocolectomy with ileal pouch-anal anastomosis has become the procedure of choice for the majority of patients with ulcerative colitis who require surgical treatment. Pouchitis, the most common long-term complication of the procedure, involves a spectrum of disease processes with heterogeneous risk factors, clinical features, disease courses and prognoses. In addition, clinical symptoms of pouchitis are not specific and often overlap with those of other inflammatory and functional pouch disorders, such as Crohn's disease of the pouch and irritable pouch syndrome. Pouchoscopy and biopsy, along with laboratory and radiographic evaluations, are often required for accurate diagnosis in patients with symptoms indicative of pouchitis. Dysbiosis has been implicated as a triggering factor for pouchitis, and concurrent infection with pathogens, such as Clostridium difficile, might contribute to disease relapse and exacerbation. Antibiotic therapy is the main treatment modality. However, the management of antibiotic-dependent and antibiotic-refractory pouchitis remains challenging. Secondary causes of pouchitis, such as ischaemia, NSAID use, the presence of concurrent primary sclerosing cholangitis and other systemic immune-mediated disorders, should be evaluated and properly managed.

Progress in understanding the role of interleukins in the pathogenesis of ulcerative colitis

Ulcerative colitis (UC) is a chronic, nonspecific inflammatory bowel disease. The assessment of UC reactiveness can be used to guide clinical treatment. Therefore, it is of important significance to find markers which have sufficient specificity and sensitivity for ease of monitoring UC. In recent years, a intensive study of the relation between interleukins (ILs) and the pathogenesis of UC has revealed changes in the secretion levels of ILs in the progression of UC, which suggests that ILs can be used as markers for monitoring the activity of UC to guide diagnosis and treatment. This paper is a review on the mechanism of action of ILs in the pathogenesis of UC.

Activation of signal transducer and activator of transcription-1 (STAT-1) and differential expression of interferon-gamma and anti-inflammatory proteins in pelvic ileal pouches for ulcerative colitis and familial adenomatous polyposis

Pouchitis after total rectocolectomy is the most common complication of ulcerative colitis (UC). The immunological mechanisms involved in the genesis of pouchitis are unclear. Therefore, we evaluated the inflammatory activity in normal ileal pouch mucosa by determining signal transducers and activators of transcription (STAT-1) activation and cytokine expression in patients operated for UC and familial adenomatous polyposis (FAP). Eighteen asymptomatic patients, who underwent total rectocolectomy and J pouch, were evaluated: nine with UC and nine with FAP. The activation of STAT-1 and cytokine expression were determined by immunoblot of total protein extracts from pouch mucosal biopsies. The absence of pouchitis was assessed by clinical, histological and endoscopic parameters, according to the Pouchitis Disease Activity Index. The patients were not receiving any medication. Analysis of variance (anova) and Tukey-Kramer's test were applied. The local ethical committee approved the study and informed consent was signed by all participants. STAT-1 activation was increased in UC when compared to FAP and controls (P < 0.05). Higher levels of interferon (IFN)-gamma expression were observed in UC patients when compared to the control group (P < 0.05), but were similar to FAP. In contrast, cytokine signalling (SOCS-3) and interleukin (IL)-10 expression were similar in all groups (P > 0.05). These findings could explain the higher susceptibility to this inflammatory complication in UC when compared to FAP. A tendency towards increased levels of IFN-gamma and STAT-1 in patients with UC, even without clinical and endoscopic evidence of pouchitis, was observed; studying inflammatory activity in asymptomatic ileal pouches may help understanding of the pathogenesis of pouchitis.

Detection of epithelial apoptosis in pelvic ileal pouches for ulcerative colitis and familial adenomatous polyposis

Background

Ileal pouch-anal anastomosis (IPAA) is the surgical procedure of choice for patients with refractory ulcerative colitis (UC) and for familial adenomatous polyposis (FAP) with many rectal polyps. Pouchitis is one of the more frequent complications after IPAA in UC patients; however, it is rare in FAP.

Objective

Evaluate pro-apoptotic activity in endoscopically and histological normal mucosa of the ileal pouch in patients with UC and FAP.

Methods

Eighteen patients (nine with UC and nine with FAP) with J pouch after total rectocolectomy were studied. Biopsies were obtained from the mucosa of the pouch and from normal ileum. The specimens were snap-frozen and the expressions of Bax and Bcl-2 were determined by immunoblot of protein extracts and by immunohistochemistry analysis. FADD, Caspase-8, APAF-1 and Caspase-9 were evaluated by immunoprecipitation and immunoblot.

Results

Patients with UC had significantly higher protein levels of Bax and APAF-1, Caspase-9 than patients with FAP, but were similar to controls. The expressions of Bcl-2 and FADD, Caspase-8 were similar in the groups. Immunohistochemistry for Bax showed less intensity of immunoreactions in FAP than in UC and Controls. Bcl-2 immunostaining was similar among the groups.

Conclusion

Patients with FAP present lower levels of pro-apoptotic proteins in all methods applied, even in the absence of clinical and endoscopic pouchitis and dysplasia in the histological analysis. These findings may explain a tendency of up-regulation of apoptosis in UC patients, resulting in higher rates of progression to pouchitis in these patients, which could correlate with mucosal atrophy that occurs in inflamed tissue. However, FAP patients had low pro-apoptotic activity in the mucosa, and it could explain the tendency to low cell turn over and presence of adenomas in this syndrome.

Pouchitis and pouch dysfunction

Restorative proctocolectomy with ileal pouch-anal anastomosis has become the surgical treatment of choice for most patients with ulcerative colitis who require surgery. Although the surgical procedure offers a cure in some patients, postoperative inflammatory and noninflammatory complications are common. Pouchitis is the most common long-term complication of the procedure. Pouchitis represents a spectrum of disease processes with heterogeneous risk factors, clinical phenotypes, natural history, and prognosis. Accurate diagnosis and classification are important for proper treatment and prognosis.

Pouchitis and pouch dysfunction

Restorative proctocolectomy with ileal pouch-anal anastomosis has become the surgical treatment of choice for most patients with ulcerative colitis who require surgery. Although the surgical procedure offers a cure in some patients, postoperative inflammatory and noninflammatory complications are common. Pouchitis is the most common long-term complication of the procedure. Pouchitis represents a spectrum of disease processes with heterogeneous risk factors, clinical phenotypes, natural history, and prognosis. Accurate diagnosis and classification are important for proper treatment and prognosis.

Pouchitis: lessons for inflammatory bowel disease

PURPOSE OF REVIEW

One of the significant limitations to the investigation of inflammatory bowel disease (IBD) in humans is the impossibility of studying this condition from the beginning of the disease process to understand the individual contribution of the various microbiological and immunological components to its pathogenesis. Pouchitis can serve as a human model for IBD, as the time of the pouch creation is known, which allows to prospectively study the events that might eventually lead to the development of a form of intestinal inflammation (i.e., pouchitis) that mimics IBD.

RECENT FINDINGS

A considerable amount of progress has been made in the last few years on the mechanisms underlying the pathogenesis of pouchitis. Recent literature suggests that pouchitis may present a spectrum of disease processes, with a wide range of causes, risk factors, clinical phenotypes, disease courses, and prognoses. Genetic, microbiological, and immunological profiles in pouchitis were evaluated.

SUMMARY

Ileal pouch and pouchitis represent a valuable human model to study the evolution of bacterial communities and host-bacteria interactions in IBD by sequentially monitoring microbiological and immunological profile before, during, and after pouch construction and before and after development and treatment of pouchitis.