Small Bowel Allograft Research Articles

Beyond 10years, with or without an intestinal graft: Present and future?

Long-term outcomes in children undergoing intestinal transplantation remain unclear. Seventy-one children underwent intestinal transplantation in our center from 1989 to 2007. We report on 10-year posttransplant outcomes with (group 1, n=26) and without (group 2, n=9) a functional graft. Ten-year patient and graft survival rates were 53% and 36%, respectively. Most patients were studying or working, one third having psychiatric disorders. All patients in group 1 were weaned off parenteral nutrition with mostly normal physical growth and subnormal energy absorption. Graft histology from 15 late biopsies showed minimal abnormality. However, micronutrient deficiencies and fat malabsorption were frequent; biliary complications occurred in 4 patients among the 17 who underwent liver transplantation; median renal clearance was 87mL/min/1.73m2 . Four patients in group 1 experienced late acute rejection. Among the 9 patients in group 2, 4 died after 10years and 2 developed significant liver fibrosis. Liver transplantation and the use of a 3-drug regimen including sirolimus or mycophenolate mofetil were associated with improved graft survival. Therefore, intestinal transplantation may enable a satisfactory digestive function in the long term. The prognosis of graft removal without retransplantation is better than expected. Regular monitoring of micronutrients, early psychological assessment, and use of sirolimus are recommended.

P2B.11: Interobserver agreement in histological diagnosis of acute cellular rejection in small bowel allografts: a multicenter study

P2B.11: Interobserver agreement in histological diagnosis of acute cellular rejection in small bowel allografts: a multicenter study

Adipose-derived mesenchymal stem cells suppress of acute rejection in small bowel transplantation.

Background/Aims:Adipose-derived mesenchymal stem cells (ADSCs) possess immunosuppressive activity and hold promise in autologous cell-based therapies. The aim of this study was to determine whether autologous ADSCs can improve outcomes in the rat small bowel transplantation (SBT) model.Materials and Methods:Allogeneic SBT followed by implantation of autologous ADSCs through the penile vein was conducted in Brown-Norway (BN) donor rats with Lewis (LEW) recipient rats infused with phosphate buffered solution as the control. Allograft and recipient peripheral blood were obtained. We assessed histopathology, apoptosis, cytokines, and regulatory T cells (Tregs). One-way analysis of variance was applied to assess the significance of the data.Results:It was found that ADSCs significantly reduced acute rejection and improved the allograft's survival rate. In addition, there were significantly fewer apoptotic cells in allograft mucosae in the ADSC group in comparison with the control group. Furthermore, levels of interleukin (IL)-10 and transforming growth factor-β1 were significantly elevated, whereas those of IL-2 and IL-17 levels were significantly reduced in the ADSC group when compared to the control group. Moreover, flow cytometry analysis revealed that there were significantly more peripheral Tregs after the infusion of ADSCs.Conclusions:These results demonstrate that implanted autologous ADSCs improve allogeneic small bowel allograft outcomes by attenuating the acute rejection and reducing inflammatory responses.

Allograft biopsy findings in patients with small bowel transplantation.

In this study, we sought to determine the incidence of post-transplant complications including acute cellular rejection (ACR), infection, and post-transplant lymphoproliferative disease (PTLD) in mucosal allograft biopsies in patients with small bowel transplant at our institution. We retrospectively reviewed pathology reports from 5675 small bowel allograft biopsies from 99 patients and analyzed the following: indications for biopsy, frequency and grade of ACR, the presence of infectious agents, results of workup for potential PTLD, results of C4d immunohistochemistry (IHC), features of chronic mucosal injury, and findings in concurrent native bowel biopsies. Findings from 42 allograft resection specimens were also correlated with prior biopsy findings. Indeterminate, mild, moderate, and severe ACR were seen in 276 (4.9%), 409 (7.2%), 100 (1.8%), and 207 (3.6%) of biopsies, respectively. Although ACR may show histologic overlap with mycophenolate mofetil toxicity, we found the analysis of concurrent native bowel biopsies to be helpful in this distinction. Adenovirus was the most common infectious agent seen (11%), and we routinely performed adenovirus IHC on biopsies. Eighteen patients (18%) developed PTLD, 83% of which were EBV associated, but only 28% of PTLD cases were diagnosed on mucosal allograft biopsies. C4d IHC did not correlate with the presence of donor-specific antibodies in limited cases.

P048 Gene expression profiling of transplant formalin-fixed paraffin-embedded biopsies: comparison of a custom TaqMan® low density array and quantitative nuclease-protection assay

Aim We developed a custom TLDA to monitor changes of gene expression in FFPE renal and small bowel allografts. Here we carried out a parallel comparison of expression profiles of marker genes obtained with TaqMan® technology and with the automated qNPA system. Methods Kidney, small bowel and heart transplant FFPE biopsies with different levels of rejection were selected. 5–6 curls of 10 μm were cut from each biopsy for analysis in TLDA (47 markers including immune, inflammatory and apoptosis genes), and in HTG Edge System using the Immuno-Oncology Expression assay (HTGIOE, 26 markers), or HTG EdgeSeq Oncology Biomarker assay (HTGESOB, 2558 genes, format for NGS). Data was presented as differential expression. Results There are 10 overlapping markers between our TLDA and the HTGIOE assay. Analysis of 30 kidney biopsies with both technologies gave similar results for all 10 markers. Several markers were not detected in some samples analyzed with the HTG Edge System, mostly in normal donor and non-rejection samples. 11 unique markers of HTGIOE assay showed potential value for monitoring gene expression in kidney. 55 samples of heart biopsies were analyzed in TLDA and HTGIOE. Similar results were obtained with both technologies for all overlapping markers. 15 useful markers for monitoring gene expression in heart were found in HTGIOE assay. HTGIOE markers often did not express in non-rejection samples. We also analyzed 17 small bowel biopsies in HTGESOB, which contains 39 of the 47 markers in our TLDA (8 for SB, 17 for both kidney and small bowel, and 14 for kidney). 17.3% of the 2558 genes in the panel showed 2-fold increase expression relative to non-rejection. 15 markers in our TLDA (6 small bowel specific, 7 for both kidney and small bowel, and 2 kidney specific) were in the 5% of markers with the highest fold change. Conclusions We showed that expression analysis carried out with TLDA and qNPA are comparable. The qNPA technology developed by HTG Molecular Diagnostics, Inc. is a good alternative to assess expression in biopsies. We found that the HTGIOE could be an excellent automated tool to evaluate panels with low number of markers in a clinical lab. The HTGESOB allows evaluation of a large number of genes, but it includes a NGS step that makes it costlier and time consuming. It is a good exploratory tool for searching new markers.

Crypt apoptotic body counts in normal ileal biopsies overlap with graft-versus-host disease and acute cellular rejection of small bowel allografts

Crypt apoptosis in intestinal epithelium is an important diagnostic feature of graft-versus-host disease (GVHD) and acute cellular rejection (ACR) of intestinal transplants (ITx). In ITx pathology, 2 or fewer apoptotic bodies in 10 consecutive crypts are considered normal, whereas 6 or more is consistent with mild ACR. The presence of 3 to 5 apoptotic bodies is problematic and is often classified as indeterminate for ACR. The minimum diagnostic threshold for GVHD is controversial but also depends on the apoptotic body count (ABC). We investigated how many crypt apoptotic bodies could be identified in histologically normal ileal biopsies from healthy subjects (native intestines, no bone marrow transplant) who underwent screening colonoscopy and had ileal biopsy to confirm complete colonoscopy. We recorded the number of biopsy pieces per specimen and the maximum ABC in 10 consecutive crypts. Twenty-six of 40 patients (65%) had an ABC of 3 or more in 10 crypts, thus only 35% were "normal." Four (10%) had an ABC of ≥6 (positive for ACR). Twenty-two (55%) had 3-5 (indefinite for ACR). Depending on the criteria, up to 60% of the cases could be diagnosed as positive for GVHD.

Anti-inflammatory Effects of Ischemic Preconditioning on Rat Small Bowel Allografts

IntroductionMinimizing the inflammatory events that follow intestinal transplantation may influence immediate graft function and improve outcome. Ischemic preconditioning (IPc) has been shown to ameliorate early inflammatory responses, and it may also attenuate the potentially damaging inflammation after intestinal transplantation. Herein, we examine the influence of intestinal IPc on inflammatory indices (tissue expression of ICAM-1, CD11a, and CD44 and serum levels of the soluble ICAM-1, sICAM-1) after heterotopic intestinal transplantation. MethodsLewis rats received full-length preconditioned or non-preconditioned Brown Norway intestinal allografts in the absence of immunosuppression. Preconditioned grafts were subjected to 1 cycle of 10 minutes of ischemia-reperfusion. Preconditioned and non-preconditioned isografts acted as controls. Blood was collected on alternate days post-transplant, and graft tissue harvested on sacrifice. ICAM-1, CD44, and CD11a expression was determined by immunohistochemistry, and the area of staining was quantified using image analysis. Serum soluble ICAM-1 levels were determined using an R&D Systems Quantikine enzyme immunoassay. Results(1) IPc ameliorated serum levels of sICAM-1 until severe rejection (day 7) overcame this down-regulation when compared to non-preconditioned allografts (day 3: 34,304 vs 40,479 pg/mL; day 5: 52,441 vs 61,593 pg/mL; day 7: 75,114 vs 73,309 pg/mL; day 9: 72,872 vs 76,314 pg/mL, respectively). (2) ICAM-1 expression was significantly lower in preconditioned allografts (1.02 vs 2.01 mm2). (3) CD44 tissue levels were also found to be lower in preconditioned allografts (0.86 vs 1.13 mm2). (4) There was a significant relationship between tissue ICAM-1 expression and serum levels of soluble ICAM-1 (P < .02). ConclusionsIPc improves inflammatory indices in the early stages following intestinal transplantation, and this might lead to a preserved cellular, architectural, and functional graft status. Furthermore, our results support the use of soluble ICAM-1 as a marker of endothelial activation, and thence of inflammation and developing rejection.

Attenuation of rat chronic small bowel allograft rejection by n‐3 polyunsaturated fatty acids is associated with reduced expression of graft IL‐15

Interleukin-15 was found to play key roles in various immunological processes including chronic rejection after renal and cardiac transplantation. n-3 polyunsaturated fatty acids (n-3 PUFA) have shown beneficial effects to chronic allograft rejection. The objective of this study is to search the possible mechanism of this inhibitory effect in chronic small bowel allograft rejection. Animals were divided into three groups: isograft (CsA+corn oil-supplemented diet); allograft (CsA+corn oil-supplemented diet); and allograft (CsA+fish oil-supplemented diet). Donor intestines from F344 rats were transplanted orthotopically into Lewis rat recipients. CsA was administered at 5mg/kg/day for 2wk post-operatively. Post-transplant weight was recorded. Histopathological changes and graft IL-15 expression were measured on POD 90. Chronic small bowel allograft rejection developed on POD 90. n-3 PUFA significantly decreased the score of chronic rejection and increased the post-operative weight gain rate. This attenuation is associated with reduced graft IL-15 expression. n-3 PUFA contributed to improved pathological and clinical outcome during chronic small bowel allograft rejection, and this improvement was associated with reduced graft IL-15 expression.

Cell Stress Response in Rat Chronic Small Bowel Allograft Rejection

BackgroundWe sought to assess the expression of five cell stress molecules: Heat shock protein (HSP)-60, HSP-70, interferon (IFN)-α, rat retinoic acid early induible-1 like transcript (RRLT), and vasoactive intestinal peptide (VIP) during rat chronic small bowel allograft rejection. MethodsA rat model of small bowel allograft rejection was induced on postoperative day 90 using F344 rat as donor and Lewis rat as recipient. ResultsWe demonstrated increased expression of lamina propria HSP-60 (mean rank grade 8.3 and 3.2, respectively), graft RRLT (relative mRNA amount 5.1 ± 1.8 and 3.0 ± 1.3, respectively) and IFN-α (relative mRNA amount 108.3 ± 49.2 and 59.2 ± 22.0, respectively) in allograft group compared with the isograft group. ConclusionThese data suggest the presence of cell stress during chronic small bowel allograft rejection.

Early onset, EBV− PTLD in pediatric liver-small bowel transplantation recipients: a spectrum of plasma cell neoplasms with favorable prognosis

AbstractEBV− posttransplantation lymphoproliferative disorders (PTLDs) are rare compared with EBV+ PTLDs, occur later after transplantation, and have a poor response to treatment. Few studies have reported EBV− PTLD in pediatric solid-organ transplantation recipients. We describe 5 cases of EBV− PTLD in recipients of combined liver and small bowel allografts ranging in age from 16 months to 7 years. EBV− PTLD developed 9-22 months (median, 15) after transplantation. Morphologically, the lesions ranged from atypical plasma cell hyperplasia (a term not currently included in the World Health Organization classification) to plasmacytoma like. In all cases, in situ hybridization for EBV was negative, and molecular studies demonstrated clonal IgH gene rearrangements. Protein electrophoresis showed multiple clonal paraproteins in 4 of 5 cases. In 2 cases with a donor-recipient sex mismatch, FISH cytogenetics demonstrated that the plasma cells were of mixed donor/recipient origin. One patient died before therapy. Four patients were treated with high-dose dexamethasone, and 1 patient subsequently required thalidomide. All 4 remain in remission 75-128 months (median, 86) after diagnosis. In contrast to reports of EBV− PTLD in adults, these plasma cell lesions occurred early after transplantation and resolved completely after minimal treatment.

Interleukin-17 plays a critical role in the acute rejection of intestinal transplantation

To investigate the role of interleukin (IL)-17 in small bowel allograft rejection. We detected the expression of helper T cell 17 (Th17) cells in biopsy specimens from 3 cases of living small bowel transplantation in our department through immunofluorescence stain. We then established a rat heterotopic small bowel transplantation model. The rats were sacrificed on the 1(st), 2(nd), 3(rd), 5(th), and 7(th) d after small bowel transplantation. The degrees of transplantation rejection in rat intestine graft were examined through hematoxylin eosin (HE) stain, and the expression of Th17 cells in rat intestine graft were detected through immunofluorescence stain. In addition, the recipient rats undergoing intestinal transplantation were administrated with mouse-anti-rat IL-17 monoclonal antibody (mAb), and the survival of rats was analyzed. The recipient rats which received mouse-anti-rat IL-17 mAb treatment were sacrificed on the 1(st), 2(nd), 3(rd), 5(th), and 7(th) d after small bowel transplantation. The degrees of transplantation rejection and the expression of Th17 cells in rat intestine graft were detected through HE and immunofluorescence stain. The expression of IL-17, IL-1β, tumor necroses factor receptor-α (TNF-α), IL-6, and IL-8 in the intestine graft or serum were also detected. The expressions of Th17 cells ran parallel with the degree of acute rejection in human intestine grafts. The intestine graft rejection of rats was aggravated with prolonged duration after intestinal transplantation, and the expressions of Th17 cells were also correlated with the degree of acute rejection in rat intestine grafts. Administration of mouse-anti-rat IL-17 mAb prolonged the survival of rats after small bowel transplantation (P < 0.001). Furthermore, we found that the administration of mouse-anti-rat IL-17 mAb significantly decreased the intensity of CD4+IL-17+ Th17 cells in intestine grafts on the 2(nd), 3(rd), 5(th), and the 7(th) d (97.22 ± 4.05 vs 12.45 ± 2.02 on the 7(th) d, P < 0.0001), and suppressed the severity of acute rejection. The expression of IL-17 in the intestine graft declined after mouse-anti-rat IL-17 mAb administration on the 2(nd), 3(rd), 5(th), and the 7(th) d (0.88 ± 0.03 vs 0.35 ± 0.02 on the 7(th) d, P < 0.0001). We also detected the IL-17 serum level and found that the IL-17 level reduced from the 1(st) d to the 7(th) d (6.52 ± 0.18 ng/mL vs 2.04 ± 0.15 ng/mL on the 7(th) d, P < 0.0001). No significant difference in the level of IL-17 mRNA in the intestine graft was identified between the two groups. The levels of IL-1β, TNF-α, IL-6, and IL-8 mRNA in the intestine graft after the administration of mouse-anti-rat IL-17 mAb were also tested. We found that on the 3(rd), 5(th), and 7(th) d after intestinal transplantation, administration of mouse-anti-rat IL-17 mAb significantly inhibited the levels of IL-1β (12.11 ± 1.16 vs 1.27 ± 0.15 on the 7(th) d, P < 0.001), TNF-α (27.37 ± 2.60 vs 1.06 ± 0.26 on the 7(th) d, P < 0.001), IL-6 (21.43 ± 1.79 vs 1.90 ± 0.32 on the 7(th) d, P < 0.001), and IL-8 (20.44 ± 1.44 vs 1.34 ± 0.20 on the 7(th) d, P < 0.001) mRNA in the intestine graft. IL-17 may act as a promising and potent target for inhibiting acute rejection after small bowel transplantation.

Histologic Analysis of Chronic Rejection in Small Bowel Transplantation

Chronic rejection is a significant barrier to small bowel allograft survival. Although chronic rejection primarily involves vessels of the submucosa, serosa, and mesentery, some mucosal alterations have been suggested to be correlative. We retrospectively investigated explanted small bowel allografts for clinical characteristics and histological alterations in the mucosa, submucosa, and serosa. Crypt epithelial mucin loss, submucosal fibrosis, and length of time to explant were all statistically associated with chronic rejection. Medium-sized and large-sized vessels of the serosa and mesentery preferentially demonstrated histologic changes of chronic rejection. These results further define chronic vascular rejection and the relationship between the mucosal changes and chronic rejection.

Role of Recipient Derived Myd88 in Small Bowel Allograft Rejection

Background: Accumulating evidence suggests that Myd88, a common adaptor protein for signal transduction of most TLRs, plays an important role in ischemia/reperfusion injury and skin and heart allograft rejection. However, little is known concerning its role in small bowel (SB) transplantation. The purpose for this study was to determine whether MyD88 deficiency in recipients alleviates SB allograft rejection. Methods: Small bowels from B6 were transplanted into either wild type (WT) or Myd88−/− BALB/c mice (allografts) heterotopically. The recipients were followed up on POD7 and POD11. Frequencies of CD4+, CD8+, CD11b+, Gr-1+, IFN-g producing T cells, IL-17 producing cells, as well as CD4+Foxp3+ cells in spleen and SB allografts were measured by flow cytometry analysis on POD7 and POD11. Morphological changes of small bowel grafts were examined by histology and phenotypes of cellular infiltrates including CD4, CD8 were identified by immunohistochemical staining on POD7 and POD11. Results: B6 to BALB/c allografts developed severe rejection manifested by loss of epithelial integrity along with diffuse infiltration by CD11b+, CD8+ and Gr-1+ cells. In contrast, Myd88−/− allograft has minimal morphological changes with a marked decrease in the number of CD11b+, CD8+ and Gr1+ cell infiltrates on both POD7 and POD11. Moreover, data from phonotypical analysis of SB infiltrating cells reveal that compared to WT allografts on both POD7 and POD11, Myd88−/− SB allografts had decreased frequencies of CD8+ cells, IFN-g producing cells and IL-17 producing cells, whereas numbers of CD4+Foxp3+ T cells were markedly increased in both spleens and SB infiltrating cells of Myd88−/− allografts. Conclusion: Our results suggest that MyD88 dependent TLR signaling plays an important role in T cell differentiation by shifting the balance between effector T cells and Tregs, thereby influencing cellular infiltration and small bowel allograft rejection.

MicroRNA Expression and Functions During Allograft Rejection

Introduction: MicroRNAs (miRNAs) are single-stranded noncoding RNA molecules of ˜22 nucleotides in length that bind to mRNAs and prevent their translation. They are an important gene regulatory step in many biological processes, and abnormal expression of miRNAs is associated with many disease states. Recent reports have demonstrated altered patterns of miRNAs in recipients of kidney and small bowel allografts. We sought to profile the miRNA expression patterns during unmodified rejection using a well-characterized experimental model of heart transplantation. Methods: Heart grafts from syngeneic (C57BL/6 —> C57BL/6) and allogeneic (BALB/c -->C57BL/6) (n=9) heterotopic heart transplants were collected 7 days after transplantation. Graft function was assessed through abdominal palpation and rejection was confirmed by histopathological analyses using H&E and Masson Trichrome staining. Samples were profiled for miRNAs using TaqMan microfluidic cards and microarray data were analyzed to define miRNAs that are differentially expressed (P< 0.05). Target predictions using both mouse and human homolog miRNA were made using TargetScan, PicTar and pathway predictions were performed using PANTHER. A luciferase reporter assay was used to determine binding of miR-132 to a predicted target USP9X. Results: Eight miRNAs, miR-10a, -20a, -132, -147b, -155, 188-5p, -221, and -424/322, were chosen for further investigation. Quantitative PCR was used to detect the kinetics of expression in heart grafts on days 1, 3, 5, and 7 post-transplant (n=3). Four distinct patterns were observed when the rejecting, allogeneic group was compared to the non-rejecting, syngeneic group. MiRs -10a, -20a and -132 demonstrated significantly elevated (3X), peak expression on day 5 post-transplant with a subsequent drop on day 7. MiRs-147b and -155 were also significantly elevated on day 5 and continued to increase through day 7 post-transplant (5X). MiRs-188-5p and -221 were moderately increased (2X) and reached a plateau by day 5 post-transplant. In contrast, expression of miR-424 was moderately decreased on day 7 post-transplant. Putative targets of each miRNA were predicted and used for pathway analysis. Results indicate that miR-20a is involved in NF-kB pathways. Mir-424 is important in cell cycle control and the Wnt pathways. Mir-221 may target genes involved in calcineurin regulation. Of note, miR-132 is predicted to target USP9X, a gene involved in deubiquination of SMAD4 in TGF-beta signaling. To confirm binding of miR-132 to USP9X, the 3′ UTR of USP9X was inserted downstream of the luciferase ORF, specific binding to miR-132 prevented luciferase reporter gene expression, however mutation of the USP9X binding site decreased specific binding to miR-132 and restored luciferase activity indicating that USP9X is a target of miR-132. Thus increased expression of miR-132 post-transplant may be important in decreasing USP9X gene expression. Interestingly, altered expression of USP9X has been reported in ischemic reperfusion injury, cardiomyopathy and during allograft rejection in the PBMC of heart transplant patients. Conclusion: Studying the roles of specific miRNA will give us insights into the regulation of key genes that control immune activation, signaling, and cell growth and suggest new targets for therapeutic intervention.

MicroRNA Expression and Functions During Allograft Rejection

Introduction: MicroRNAs (miRNAs) are single-stranded noncoding RNA molecules of ˜22 nucleotides in length that bind to mRNAs and prevent their translation. They are an important gene regulatory step in many biological processes, and abnormal expression of miRNAs is associated with many disease states. Recent reports have demonstrated altered patterns of miRNAs in recipients of kidney and small bowel allografts. We sought to profile the miRNA expression patterns during unmodified rejection using a well-characterized experimental model of heart transplantation. Methods: Heart grafts from syngeneic (C57BL/6 —> C57BL/6) and allogeneic (BALB/c —>C57BL/6) (n=9) heterotopic heart transplants were collected 7 days after transplantation. Graft function was assessed through abdominal palpation and rejection was confirmed by histopathological analyses using H&E and Masson Trichrome staining. Samples were profiled for miRNAs using TaqMan microfluidic cards and microarray data were analyzed to define miRNAs that are differentially expressed (P< 0.05). Target predictions using both mouse and human homolog miRNA were made using TargetScan, PicTar and pathway predictions were performed using PANTHER. A luciferase reporter assay was used to determine binding of miR-132 to a predicted target USP9X. Results: Eight miRNAs, miR-10a, -20a, -132, -147b, -155, 188-5p, -221, and -424/322, were chosen for further investigation. Quantitative PCR was used to detect the kinetics of expression in heart grafts on days 1, 3, 5, and 7 post-transplant (n=3). Four distinct patterns were observed when the rejecting, allogeneic group was compared to the non-rejecting, syngeneic group. MiRs -10a, -20a and -132 demonstrated significantly elevated (3X), peak expression on day 5 post-transplant with a subsequent drop on day 7. MiRs-147b and -155 were also significantly elevated on day 5 and continued to increase through day 7 post-transplant (5X). MiRs-188-5p and -221 were moderately increased (2X) and reached a plateau by day 5 post-transplant. In contrast, expression of miR-424 was moderately decreased on day 7 post-transplant. Putative targets of each miRNA were predicted and used for pathway analysis. Results indicate that miR-20a is involved in NF-κB pathways. Mir-424 is important in cell cycle control and the Wnt pathways. Mir-221 may target genes involved in calcineurin regulation. Of note, miR-132 is predicted to target USP9X, a gene involved in deubiquination of SMAD4 in TGF-beta signaling. To confirm binding of miR-132 to USP9X, the 3' UTR of USP9X was inserted downstream of the luciferase ORF, specific binding to miR-132 prevented luciferase reporter gene expression, however mutation of the USP9X binding site decreased specific binding to miR-132 and restored luciferase activity indicating that USP9X is a target of miR-132. Thus increased expression of miR-132 post-transplant may be important in decreasing USP9X gene expression. Interestingly, altered expression of USP9X has been reported in ischemic reperfusion injury, cardiomyopathy and during allograft rejection in the PBMC of heart transplant patients. Conclusion: Studying the roles of specific miRNA will give us insights into the regulation of key genes that control immune activation, signaling, and cell growth and suggest new targets for therapeutic intervention.

Six Months Fish Oil Ameliorates the Small Bowel Allograft Arteriosclerosis by Reduction in Intestine Cholesterol Absorption

Six Months Fish Oil Ameliorates the Small Bowel Allograft Arteriosclerosis by Reduction in Intestine Cholesterol Absorption

Two-Photon Microscopy Reveals Changes in Cellular Morphology and NADH and FAD Oxidation-Reduction States in Ischemic Small Bowel Allografts

Two-Photon Microscopy Reveals Changes in Cellular Morphology and NADH and FAD Oxidation-Reduction States in Ischemic Small Bowel Allografts

Systematic Protocol Biopsy of the Duodenal Graft for Surveillance after Pancreas Transplantation

Introduction: We present data on serial protocol biopsies (px) of the duodenal graft by double-balloon enteroscopy (DBE) for surveillance of rejection and local CMV infection in patients undergoing either single pancreas (SPT) or combined pancreas and kidney transplantation (SPK). Methods: Between August 2009 and December 2011, 39 pancreas transplantations (SPK n= 31; SPT n= 8) were performed. All patients underwent consecutive px of the duodenal graft at 1, 3, 6 and 12-month post-transplant. Thereafter, duodenal-px was continued yearly and/or on-demand basis. Rejection was evaluated according to the Banff criteria for small bowel allografts. All samples were immunostained for focal cytomegalovirus (CMV) infection. Results: Patient and survival rate for the study cohort were 100%. Overall 86 mucosal px of the duodenal graft were obtained in 36 patients. No procedure-related complications were observed. DBE was feasible in 90% of the study cohort. In 7 out of 39 patients (17.9%) (SPK n= 4; SPT n=3) rejection was diagnosed in the duodenal graft. All patients in the SPK group presented also rejection in the kidney graft, either simultaneously (n= 2) or previous to the duodenal px (n= 2, 14 and 50 days pre-duodenal-px). In SPT group, subclinical rejection was diagnosed in 3 of 8 patients. Local CMV-infection was detected in 5 patients (13%) (SPK n= 3; SPT n= 2). In 1 patient with focal CMV infection, spontanuous perforation of the duodenal graft was observed at 1-month. Subsequent duodenal px at 1-month post-treatment showed reversal of both rejection episodes and focal CMV-infections. Conclusion: Serial protocol px of the duodenal segment of the pancreas graft by DBE is safe and might represent an effective method for surveillance of both rejection and focal CMV-infection after clinical pancreas transplantation.

Six Months Fish Oil Ameliorates the Small Bowel Allograft Arteriosclerosis by Reduction in Intestine Cholesterol Absorption

Six Months Fish Oil Ameliorates the Small Bowel Allograft Arteriosclerosis by Reduction in Intestine Cholesterol Absorption

Two-Photon Microscopy Reveals Changes in Cellular Morphology and NADH and FAD Oxidation-Reduction States in Ischemic Small Bowel Allografts

Two-Photon Microscopy Reveals Changes in Cellular Morphology and NADH and FAD Oxidation-Reduction States in Ischemic Small Bowel Allografts