A Central Role for Lipocalin-2 in the Adaptation to Short-Bowel Syndrome Through Down-Regulation of IL22 in Mice.

BACKGROUND & AIMS: In short-bowel syndrome (SBS), inadequate intestinal adaptation is responsible for the majority of complications, including sepsis, liver failure, and death. In this study, we sought to further delineate the adaptive response to identify potential therapeutic targets. METHODS: We performed a 75% small-bowel resection (SBR) or sham operation on C57Bl/6J wild-type (WT), lipocalin-2 (LCN2)-/-, and interleukin 22 (IL22)-/- mice. Exogenous IL22 was administered to SBR WT mice. Cecal fecal matter from SBR WT and SBR LCN2-/- mice were transplanted into germ-free mice. Intestinal permeability, inflammation, proliferation, and the microbiome were evaluated 1 week after surgery. CD4+IL22+ laminal propria lymphocytes were sorted by flow cytometry. Naïve T cells were polarized to T-helper cells with or without LCN2. RESULTS: A 75% SBR in a mouse re-creates the increased intestinal permeability, enterocyte proliferation, and intestinal dysbiosis seen in SBS. LCN2 expression increases after 75% SBR, and this increase can be abrogated with broad-spectrum antibiotic treatment. LCN2-/- mice have less intestinal inflammation, increased IL22 expression, and greater adaptation as evidenced by less intestinal permeability, increased carbohydrate enzyme expression, less weight loss, and less dysbiosis after 75% SBR than WT mice. The proinflammatory and anti-adaptive effects of LCN2 can be transferred to germ-free mice via a fecal transplant. Administration of exogenous IL22 improves adaptation and restores the normal microbiome after 75% SBR in WT mice. CONCLUSIONS: LCN2 promotes inflammation and slows intestinal adaptation through changes in the microbiome and IL22 inhibition in a mouse SBS model. Strategies to reduce LCN2 may offer novel therapeutic approaches to enhance adaptation in SBS.

An exclusive human milk diet for very low birth weight newborns-A cost-effectiveness and EVPI study for Germany.

OBJECTIVES: Human milk-based fortifiers have shown a protective effect on major complications for very low birth weight newborns. The current study aimed to estimate the cost-effectiveness of an exclusive human milk diet (EHMD) compared to the current approach using cow's milk-based fortifiers in very low birth weight newborns. METHODS: A decision tree model using the health states of necrotising enterocolitis (NEC), sepsis, NEC + sepsis and no complication was used to calculate the cost-effectiveness of an EHMD. For each health state, bronchopulmonary dysplasia (BPD), retinopathy of prematurity (RoP) and neurodevelopmental problems were included as possible complications; additionally, short-bowel syndrome (SBS) was included as a complication for surgical treatment of NEC. The model was stratified into birth weight categories. Costs for inpatient treatment and long-term consequences were considered from a third party payer perspective for the reference year 2017. Deterministic and probabilistic sensitivity analyses were performed, including a societal perspective, discounting rate and all input parameter-values. RESULTS: In the base case, the EHMD was estimated to be cost-effective compared to the current nutrition for very low birth weight newborns with an incremental cost-effectiveness ratio (ICER) of €28,325 per Life-Year-Gained (LYG). From a societal perspective, the ICER is €27,494/LYG using a friction cost approach and €16,112/LYG using a human capital approach. Deterministic sensitivity analyses demonstrated that the estimate was robust against changes in the input parameters and probabilistic sensitivity analysis suggested that the probability EHMD was cost-effective at a threshold of €45,790/LYG was 94.8 percent. CONCLUSION: Adopting EHMD as the standard approach to nutrition is a cost-effective intervention for very low birth weight newborns in Germany.

The impact of intestinal resection on the immune function of short bowel syndrome patients.

Short bowel syndrome (SBS) is characterized by a massive intestinal loss after surgery resection. Likewise, disturbances involving the intestine, which represents a complex immune environment, may result in breakdown of homeostasis and altered responses, thus leading to unpredictable clinical outcomes. However, the consequences of bowel resection were poorly investigated until now. Therefore, this study aimed to evaluate the immunological status of SBS-patients. For this purpose, ten subjects and nine healthy controls were evaluated. Along with some metabolic disturbances, the main results showed higher levels of the inflammatory cytokine IL-6 in plasma among SBS-patients. However, there were no differences in the frequency of CD3+, CD3+CD4+ or CD3+CD8+ T lymphocytes. An augmented frequency in CD4+ and CD8+ cells producing IFN-γ was also observed in peripheral blood mononuclear cells (PBMC), together with elevated percentage of CD4+ cells producing IL-10. No differences were observed in the frequency of total CD4+CD25-, CD4+CD25+ lymphocytes nor in the expression of FoxP3 or GITR. Nevertheless, SBS-patients showed higher frequency of the regulatory T cell population CD4+CD25+CD39+ cells in PBMC. In conclusion, these data pointed to SBS as an important disturbance that compromises not only the intestinal environment but also negatively influences systemic immune components.

Updates on acute and chronic rejection in small bowel and multivisceral allografts.

PURPOSE OF REVIEW: The surgical management of short bowel syndrome now includes intestinal (ITx) and multivisceral transplantation (MVTx), which has advanced and is now a sustainable option for the treatment of intestinal failure. Improvements in immunosuppressive therapies, excellence in surgical and medical management and enhanced post-transplant monitoring have all contributed to optimizing this solid organ transplant as a means of supplanting the diseased native bowel and alimentary tract with a functional alternative. RECENT FINDINGS: Post-transplant management is a critical and challenging phase of gastrointestinal transplantation, and the transplant pathologist is an essential member of the transplant team who identifies many of the early and late complications after ITx and MVTx. Among the most injurious and common complications of ITx and MVTx is acute rejection and, to a lesser degree, chronic rejection. Both of these broad categories of rejection are principally identified by histopathological changes in the allograft; however, biomarkers and other laboratory analytes are rapidly evolving into critical ancillary tools in identifying and further characterizing the rejection process. Thus, the transplant pathologist must also be able to utilize numerous other laboratory tests and panels of molecular biomarkers that provide supplementary information to accompany the biopsy interpretation and clinical suspicion of rejection. SUMMARY: Using biopsies and an assortment of additional approaches, the transplant pathologist is now able to provide swift and detailed information regarding the rejection process in the gastrointestinal transplant. This enables the clinical team to properly and successfully intercede, contributing to enhanced patient and graft survival.

Jejunoileal bypass as the main procedure in the onset of immune-related conditions: the model of BADAS.

Bariatric surgery represents a common approach for the control of severe morbid obesity, reducing caloric intake by modifying the anatomy of the gastrointestinal tract. Following jejunoileal bypass, a large spectrum of complications has been described, with rheumatic manifestation present in up to 20% of cases. Although bowel bypass syndrome, also called blind loop syndrome, is a well-recognized complication of jejunoileal bypass, the same syndrome was recognized in patients who had not had intestinal bypass surgery, and the term the 'bowel-associated dermatosis-arthritis syndrome' (BADAS) was coined. The pathogenesis of BADAS is as yet poorly understood and only few data concerning this issue have been published in the literature. The aim of the present paper is to review the literature and to discuss putative pathogenic mechanisms of BADAS, focusing on the immune system.

Development of Crohn's disease in patients with intestinal failure: a role for bacteria?

We present 3 cases of Crohn's disease that developed in patients with previously diagnosed short bowel syndrome from another cause. There are characteristics unique to patients with short bowel syndrome that may increase their likelihood to develop Crohn's disease, based on current concepts of the pathophysiology of inflammatory bowel disease. These patients may have a higher than average prevalence of small intestinal bacterial overgrowth. This may lead to an increase in bacterial translocation and dysregulation of the intestinal immune response. In addition, these patients often require parenteral nutrition (PN) because of macronutrient and micronutrient deficiencies. Some patients receiving PN, particularly those with bowel obstructions, may be at risk for septicemia due to bacterial translocation. It is thought that PN may enhance intestinal dysmotility and impair gut immunity, contributing further to an antigenic immune response in the intestinal immune system, although supporting data is lacking. Finally, studies have demonstrated that patient's with Crohn's disease have a shorter bowel length before any intestinal resections and not related to disease activity. Although the significance of this is unclear, a shorter bowel length may potentially predispose people to the development of Crohn's disease via an alteration of intestinal motility and intestinal flora.

How immunocompromised are short bowel patients receiving home parenteral nutrition? Apropos a case of disseminated Fusarium oxysporum sepsis.

BACKGROUND: Catheter-related sepsis is the most frequent complication in patients receiving home parenteral nutrition (HPN) for short bowel syndrome (SBS). A low-grade systemic inflammatory state and an altered mucosal immune response, as well as diminished intestinal barrier function have been characterized in these patients. The possibility of systemic immunocompromise has only recently been suggested. CASE DESCRIPTION: A 45-year-old female with traumatic SBS was admitted for possible catheter-related sepsis. She was asplenic and had insulin-dependent diabetes mellitus as a result of a pancreatic resection. A large skin ulceration was present on her left calf, which appeared unusual for a disseminated bacterial infection. Chest x-ray and computed tomography scan revealed multiple subpleural pulmonary infiltrates consistent with bacterial or fungal dissemination. Blood cultures from the port system and from the peripheral blood grew Staphylococcus haemolyticus and Fusarium oxysporum. The port system was removed, and flucloxacillin and voriconazole were given for 33 and 35 days, respectively. Clinical signs of disseminated sepsis resolved slowly. Bone marrow biopsy ruled out primary hematologic disease. CONCLUSIONS: (1) Catheter-related sepsis in patients on HPN is usually caused by Gram-positive or Gram-negative bacteria or by Candida species. Identification of molds in blood cultures strongly suggests Fusarium species, which should be treated appropriately with voriconazole or amphotericin B. (2) HPN and SBS aggravated by asplenism and diabetes mellitus can cause severe immunocompromise. (3) Fusaria have a strong tendency to persist or reappear after bone marrow transplantation, which is therefore relatively contraindicated in these patients.

Primer trasplante de intestino en Chile: Caso clínico / Small bowel transplantation: Report of a single case

Small bowel transplantation is associated with a patient survival atone and five years, of 80% and 63%, respectively. We report a 36 year-old female with short bowel syndrome, subjected to the first small bowel transplantation performed in Chile. A cadaveric graft was used. Immunosuppression was achieved by means of alemtuzumab, tacrolimus, sirolimus, micofenolate mofetil and steroids. Serial endoscopies and biopsies were performed during sevenmonths after transplantation. The most important late complications were a drug induced renal failure, infections caused by opportunistic agents and a gastrointestinal bleeding probably induced by drugs. After 29 months of follow up, the patient is ambulatory, on oral diet only, and with no evidence of graft rejection.

Oral antibiotics attenuate bowel segment reversal-induced alterations in subpopulation and function of peripheral blood leukocytes, thymocytes, and splenocytes in massive bowel-resected rats.

BACKGROUND: The authors previously demonstrated that oral antibiotics significantly attenuated inflammatory response, improved intestinal bacterial overgrowth, and augmented anabolic response in massive bowel-resected rats with bowel-segment reversal. Herein, the effects of oral antibiotics on immune functions were investigated. METHODS: Male Wistar rats were subjected to a sham operation or a 70% small bowel resection with or without a 3-cm small bowel segment reversal. Thereafter, half numbers of animals with bowel resection and reversal were orally administered clindamycin plus amoxicillin (50 plus 50 mg/kg/day) for 3 weeks. Age-matched nonsurgical rats were included as references. Peripheral blood, spleen, and thymus were collected for analyzing immunocyte subpopulations and function. RESULTS: Bowel resection significantly decreased weight gain, thymic weight, and splenic helper-T, suppressor-T, and mature-B cells but significantly increased splenic macrophage distribution and concanvavalin A-stimulated splenocytic proliferation and cytokine production, such as tumor-necrosis factor (TNF)-alpha, interferon-gamma, and interleukin (IL)-2 (1-way ANOVA, P<.05). Bowel segment reversal further decreased circulating suppressor-T cells but increased circulating natural killer cells and spontaneous splenocytic TNF-alpha production. Segment reversal-induced elevations in bacterial numbers of gut content, circulating white blood cell, nitric oxide, IL-6, splenocytic interferon-gamma and IL-2 production, reductions in T-thymocytic distribution, and alterations in thymocytic interferon-gamma and IL-2 production were attenuated by oral antibiotics. Moreover, oral antibiotics significantly increased splenocytic granulocytes and spontaneous thymocytic proliferation. CONCLUSIONS: Oral antibiotics might augment the beneficial effects of bowel segment reversal on anabolism via attenuating bacterial overgrowth and inflammatory response, and restore subpopulation and function of splenocytes and thymocytes in massive bowel-resected rats.

Immunonutritional effects during synbiotics therapy in pediatric patients with short bowel syndrome.

The aim of this study was to evaluate the effects of synbiotic therapy in patients with short bowel syndrome (SBS). Four pediatric patients with SBS, who were receiving synbiotics therapy including Bifidobacterium breve, Lactobacillus casei and galactooligosaccharides, were enrolled in this study. We evaluated changes in immunonutritional parameters before and after receiving synbiotics therapy. Four normal, healthy, age-matched children were enrolled as controls. Fecal samples from patients and controls were collected and analyzed for fecal bacterial flora and organic acid (OA) contents. Levels of short chain fatty acids (SCFA) such as butyrate, propionate, and acetate increased in one patient, and SCFA/total OA levels increased in three patients. Serum lymphocyte counts and concentrations of pre-albumin increased after beginning synbiotics therapy, reaching a statistically significant level at the ninth month compared to the pre-treatment level. There was an increasing trend in height and weight gain velocity during the study compared with the pre-treatment period. The patients' fecal bacterial flora improved as a result of synbiotics therapy. Synbiotics therapy may be very effective at improving the intestinal flora and systemic immunonutritional status of patients with SBS.

Inflammatory mediators and immune function are altered in home parenteral nutrition patients.

OBJECTIVES: Patients who used home parenteral nutrition (HPN) and healthy, volunteer control subjects were examined to assess relative immune potential and inflammatory marker expression and to investigate the association between HPN and immune parameters. METHODS: Subjective Global Assessments were performed on all subjects. The peripheral blood concentration of C-reactive protein was determined by enzyme-linked immunosorbent assay. The peripheral blood concentration of systemic inflammatory mediators that included tumor necrosis factor-alpha (TNF-alpha), soluble TNF-alpha receptors p55 and p75, and interleukin-6 were similarly determined. Peripheral blood lymphocytes were isolated and the percentage of circulating CD4+ and CD8+ lymphocytes was determined by flow cytometry. In addition, peripheral blood lymphocytes were cultured in the presence of the T-cell mitogen, phytohemagglutinin, and the proliferative response of the CD3+ population was assessed by flow cytometry. Results of these experiments were obtained for 10 clinically stable patients who had used HPN longer than 2 y and these results were compared by Student's t test with data obtained for 12 normal, volunteer control subjects. RESULTS: Of the 10 patients who used HPN and were examined, seven had short bowel syndrome, two had dysmotility, and one required HPN due to radiation enteritis. Based on Subjective Global Assessments, all patients were well nourished. No difference was observed in TNF-alpha level between groups and C-reactive protein levels were within normal limits (1.2 mg/L in patients, 0.99 mg/L in controls). Soluble TNF-alpha receptors p55 and p75 were significantly increased (P < 0.001), but serum interleukin-6 was not (P = 0.07). The percentage of CD8+ cells and the CD4+/CD8+ ratio were not statistically different between groups. In contrast to this result, the percentage of CD4+ cells and the proliferative T-cell response to phytohemagglutinin were significantly depressed in patients who used HPN versus control subjects. CONCLUSIONS: These data suggest the presence of an underlying inflammatory process and subsequent abnormal T-lymphocyte function in patients who use HPN.

Gene alteration of intestinal intraepithelial lymphocytes in response to massive small bowel resection.

BACKGROUND: The intestinal adaptive response [increased epithelial cell (EC) proliferation and apoptosis] after massive small bowel resection (SBR) is partially controlled by intraepithelial lymphocytes (IEL). To identify IEL factors contributing to EC adaptation post-SBR we utilized microarray assays. METHODS: Mice underwent a 70% SBR (SBR1w/SBR4w) or sham operation (Sham1w/Sham4w). After 1 or 4 weeks (1w, 4w) small bowel was harvested, and IEL isolated. Determination of the EC-proliferation rate used BrdU incorporation, and of the EC-apoptotic rate used Annexin V staining. Affymetrix system microarrays (12,491 genes) were performed to examine IEL-mRNA expression. Results were considered significant if fold-change (FC) between groups was >2 and P<0.05 (F-test), or FC>3 and 0.05> P >0.01, or FC>4 and P>0.05. Significant genes were confirmed by conventional RT-PCR. RESULTS: The SBR EC-proliferation rate increased significantly in both 1w and 4w groups compared to Sham: SBR1w 0.24+/-0.07 vs. Sham1w 0.12+/-0.02 (P=0.03); SBR4w 0.35+/-0.04 vs. Sham4w 0.19+/-0.02 ( P<0.01). The EC-apoptotic rate was unchanged in the 1w group, but significantly differed from controls after 4 weeks: SBR4w 39.92+/-6.78 vs. Sham4w 12.56+/-6.44 ( P<0.01). Microarray results were analyzed to identify potential growth-modifying IEL genes. The following were identified (function in parenthesis; A, apoptosis; P, proliferation): lipocalin 2 (promotes A), angiotensin converting enzyme (increases A), Rap2 interacting protein (reduces A, promotes P), amphiregulin (promotes P) and leucine-rich-alpha2-glycoprotein (promotes A, reduces P). Based on RT-PCR results these genes showed significant changes between groups. The increase in ACE at 1w preceded the observed apoptotic changes. The alterations in lipocalin 2, Rap2 and amphiregulin at 4w coincided with the marked changes in growth and apoptosis in the SBR mice. CONCLUSIONS: IEL undergo temporal changes after SBR. These findings provide profound insight into potential IEL-dependent regulation of EC homeostasis post-SBR.

The effect of mesenteric lymphadenectomy and Kupffer cell depletion on bacterial translocation.

BACKGROUND: Infectious complications are associated with high morbidity in patients with short bowel syndrome and after small bowel transplantation. Bacterial translocation from the intestine is probably an essential factor in the genesis of these infections. In a model for bacterial translocation in the rat we examined the consequence of mesenteric lymphadenectomy and the depletion of Kupffer cells. MATERIALS AND METHODS: The effect of mesenteric lymphadenectomy was studied in two different models; in rats where a Thiry-Vella loop had been created from small bowel and in rats that had received a syngeneic small bowel transplant. To study the role of the Kupffer cells, rats with Thiry-Vella loops were treated intravenously with the Kupffer cell inhibitor gadolinium chloride. All animals were sacrificed on Day 3 postoperatively and the bacterial translocation to the mesenteric lymph nodes, liver, spleen, lung, and blood was evaluated. RESULTS: Removal of the mesenteric lymph nodes did not result in any increased bacterial translocation in animals with a Thiry-Vella loop. However, the inactivation of Kupffer cells with gadolinium chloride produced a more severe translocation to the liver, spleen, and lungs. After small bowel transplantation the bacterial translocation to the spleen was increased in animals without mesenteric lymph nodes. CONCLUSIONS: In the model of bacterial translocation from a defunctionalized loop of small bowel the inhibition of Kupffer cells will promote the systemic spread of the translocating bacteria. This indicates an important protective function of the Kupffer cells against translocating microbes.

T-cell dysfunction in a patient with short bowel syndrome: report of a case.

We describe herein the case of a 48-year-old man who underwent emergency massive resection of the small intestine due to strangulated ileus, which led to short bowel syndrome (SBS) as he was left with 7 cm of jejunum and 8 cm of ileum. We evaluated the immune function in this patient, focusing particular attention on T-cell-mediated immunity. Biochemical and nutritional parameters, including minerals and trace elements, indicated that the patient was in relatively good health; however, the proliferative response to mitogen and tumor necrosis factor-alpha production in response to the anti-CD3 monoclonal antibody in peripheral blood lymphocytes (PBL) were impaired compared with age-matched postgastrectomy patients and healthy donors. Moreover, the expression of T-cell receptor (TCR) zeta, which is involved in signal transduction and the subsequent activation of T cells, was downregulated in this patient compared with that in the age-matched postgastrectomy patients and healthy donors. These observations suggest that T-cell function was disturbed in our patient, and that this dysfunction was associated with the decreased expression of TCR zeta molecules.

Bacterial translocation and T-lymphocyte populations in experimental short-bowel syndrome.

Bacterial translocation (BT) accounts in part for sepsis in short-bowel syndrome in which total parenteral nutrition (TPN) is routinely necessary. TPN "per se" facilitates BT and it has been suggested that decreased T-lymphocyte populations (TLP) in newborn rabbits and nude mice promote BT as well. We have tested the hypothesis that BT and modifications in TLP are to be expected in rats subjected to TPN and gut resection. Forty-five adult Wistar rats underwent central venous cannulations and were randomly assigned to one of three groups receiving for ten days three treatment regimes: - Group Sham (n = 17) oral intake of rat chow + saline (300 ml/kg/24 h) through a jugular vein catheter. - Group TPN (n = 17) fasting + infusion of all-in-one TPN solution (300 ml/kg/24 h). - Group RES (n = 11) fasting, same TPN regime + 80% gut resection. At the end of the experiment they were sacrified and specimens (peripheral and portal blood, spleen and mesenteric lymph nodes) were recovered, cultured and/or assessed for CD4+ and CD8+. Bacterial translocation was found in 47% of TPN animals, 92% of RES rats, but not in SHAM ones. Lymphocyte populations were not different in BT+ (n = 8) or BT- (n = 9) rats in the TPN group. TPN and resected animals showed a rise in CD4+ and a drop in CD8+ (then a better CD4+/CD8 ratio) when comparing with SHAM group rats. From this data we may conclude that: 1) BT is frequent if TPN is administered, and constant in resected animals. 2) No apparent relationship between the proportions of CD4+ and CD8+ lymphocytes and BT could be shown in TPN group. 3) High CD4+/CD8+ ratio in TPN and RES groups demonstrate that BT is possible even having good TLP.

Cytokine gene transcription by NF-kappa B family members in patients with inflammatory bowel disease.

We examined the expression of the transcription factor NF-kappa B, a nuclear trans-acting factor known to play a key role in cytokine gene regulation, in patients with inflammatory bowel disease (IBD). It was found that LP macrophages in Crohn's disease (CD) and ulcerative colitis (UC) display high levels of NF-kappa B DNA-binding activity accompanied by an increased production of interleukin (IL)-1, IL-6, and tumor necrosis factor (TNF) alpha. Western blot studies showed an increased expression of the p50 and c-rel subunits of NF-kappa B; however, the most striking finding was an increased expression level of NF-kappa B p65 in patients with CD and UC. Selective downregulation of p65 in IBD macrophages by a specific antisense phosphorothioate oligonucleotide was sufficient to considerably reduce production of proinflammatory cytokines. These results demonstrate a characteristic increase of NF-kappa B binding levels in patients with IBD. The data suggest that antisense DNA targeting NF-kappa B p65 can be used as a novel molecular approach for the treatment of patients with IBD.

Trophic effects of interleukin-11 in rats with experimental short bowel syndrome.

Interleukin-11 (IL-11) is a multifunctional cytokine, derived from bone marrow stromal cells, that stimulates proliferation of stem/progenitor precursor cells in the small intestinal crypts and accelerates recovery of intestinal mucosa after cytoablative therapy. This study evaluates whether IL-11 can improve the function and structure of the small intestine and enhance adaptation in an experimental model of short bowel syndrome. After 90% small bowel resection, 32 Sprague-Dawley rats were divided randomly into eight experimental groups of four animals each. Four groups were treated with IL-11 (125 micrograms/kg twice daily, subcutaneously), and the four control groups were treated with a similar volume (0.1%) of bovine serum albumin (BSA). The animals were weighed daily and were killed on day 2, 4, 6, or 8; remnant small bowel was evaluated for villus height and crypt cell mitosis. The body weight of the animals that received IL-11 was significantly greater at the beginning of postoperative day 4 in comparison to that of the BSA groups (P < .01 during days 5 to 7). The rats that had IL-11 also had significantly greater villus height and crypt cell mitotic rates (P < .05). These observations suggest that IL-11 has a trophic effect on the small bowel during the adaptive phase that follows massive bowel resection and may be useful in the treatment of short bowel syndrome.