Outcome of adrenal tissue fragments allotransplantation: the impact of cryopreservation.

Cryopreservation is thought to have the potential to preserve tissue for transplantation. In addition, it can also be used for decreasing tissue immunogenicity, which might be important for prolonging allograft survival. In the present study we examined the impact of cryopreservation at various cooling rates on the outcome of allotransplantation of murine adrenal tissue fragments (ATFr). ATFr were cryopreserved with a cooling rate at 1; 10; 40 and more than 100 °C/min. After thawing it was found that the number of the cells expressing markers of dendritic cells (CD11c) and macrophages (CD11b) in the suspension obtained from ATFr decreased with increasing cooling rate. After allotransplantation the survival rates of adrenalectomized mice and the blood serum levels of corticosterone were higher in recipients of cryopreserved ATFr. By immunohistochemistry, cryopreserved allografts displayed a decreased infiltration by CD4+ and CD8+ T-lymphocytes as compared to fresh grafts. These findings suggest that cryopreserved allografts cause a less severe rejection by decreasing graft immunogenicity.

Colonic ischaemia as a severe Shiga toxin/verotoxin producing Escherichia coli O104:H4 complication in a patient without haemolytic uraemic syndrome, Germany, June 2011.

An increasing rate of infections with Shiga toxin/verotoxin-producing Escherichia coli (STEC/VTEC) O104:H4 has been observed in Germany since May 2011, with unusually high numbers of patients suffering from haemolytic uraemic syndrome (HUS). We report a STEC/VTEC O104:H4 case without HUS, presenting with colonic ischaemia demanding surgery. This atypical clinical presentation of STEC O104:H4 infection might indicate new severe complications associated with this uncommon strain, and highlights the importance of immediate interdisciplinary assessment of STEC/VTEC patients.

[Intraoperative pitfalls and complications in defecation disorders and rectal prolapse]. / Intraoperative Fallstricke und Komplikationen bei Stuhlentleerungsstörung und Rektumprolaps.

BACKGROUND: No generally accepted gold standard exists for the operative therapy of rectal prolapse in its variety of manifestations. Existing evidence suggests that an individualized choice of procedure provides the best result for each single patient. Knowledge of possible pitfalls and intraoperative management of complications in frequently applied procedures are important prerequisites for reliable treatment of affected patients. MATERIAL AND METHODS: A consecutive series of 233 patients (June 2011-May 2016) with individualized choice of operative procedure in patients with rectal prolapse and rectocele based on an algorithm for a clinical treatment pathway and stapled hemorrhoidopexy were included. Intraoperative pitfalls and complications and their management (iPCM) were prospectively documented and analyzed. RESULTS: The iPCM could be classified into three different categories: group I: iPCM was immediately noted and intraoperatively treated with no impact on the further clinical course (n = 20), group II: iPCM was successfully treated conservatively within a short time after the procedure (n = 9) and group III: iPCM required surgical revision (n = 5). CONCLUSION: Individualized treatment of rectal prolapse and rectocele requires a broad spectrum of methods in specialized coloproctology units. A clinical treatment pathway facilitates the optimal choice of procedure. Overall the complication rates during surgical treatment of transanal rectal prolapse are low; however, available operative procedures hold specific risks and knowledge of these risks helps to avoid them. Once complications occur, measures demonstrated in this study lead to normal clinical courses in the majority of cases.

Control of intestinal allograft rejection by FTY720 and costimulation blockade.

INTRODUCTION: The clinical application of small bowel transplantation (SBTx) is hampered by its pronounced immunogenicity. In this study we examined the effects of the novel immunosuppressant FTY720 and costimulation blockade by an anti-CD40L mAb (MR-1) in a stringent mouse model of SBTx. METHODS: SBTx was performed in mice with a full MHC mismatch (donors: C3H=H-2(k); recipients: C57BL/6=H-2(b)). Recipients were divided into four groups: 1, untreated group; 2, MR1 monotherapy (500 microg IV on days 0, 2, 4, and 7); 3, FTY720 monotherapy (1 mg/kg body weight PO for 14 consecutive days after transplantation); 4, FTY720 plus MR1-treated group. Graft rejection grades were assessed by H&E staining. Graft mesenteric lymph nodes (MLNs), Peyer's patches (PPs), as well as intraepithelial lymphocytes (IELs) and lamina propria lymphocytes (LPLs) were analyzed by flow cytometry and three-color immunofluorescence staining. RESULTS: Neither FTY720 nor MR1 monotherapy was efficient in preventing the rejection of mouse intestinal allografts, whereas FTY720 plus MR1 profoundly inhibited the rejection response at the 14th posttransplant day. The infiltration of host lymphocytes was reduced in graft MLNs, PPs, IELs, and LPLs by FTY720 therapy. FTY720 plus MR1 inhibited host CD8(+) T-cell infiltration in graft LPLs when compared with grafts treated with FTY720 only. Additionally, two subpopulations, CD11b(+high) Gr1(-) and CD11b(+intermediate) Gr1(+) cells, were decreased in FTY720-treated grafts. CONCLUSIONS: FTY720 plus MR1 efficiently delayed intestinal allograft rejection in a mouse model by preventing the infiltration of host lymphocytes, particularly of CD8(+) cells.

Production of cytokines (TNF-alpha, IL-1-beta) and endothelial cell activation in human liver allograft rejection.

Intragraft production of tumor necrosis factor-alpha (TNF-alpha) and interleukin-1-beta (IL-1-beta) was determined in rejecting human liver grafts during acute rejection and in chronic graft dysfunction. The localization of cytokine-producing cells was then correlated with the distribution of monocytes and macrophages as their main producers, as well as with effector functions such as endothelial cell activation. In selected patients collateral TNF-alpha plasma levels were measured. In normal liver and biopsies taken during an uncomplicated course, few TNF-alpha and even fewer IL-1-beta positive macrophages were found. During acute rejection episodes of all degrees of severity liver grafts were infiltrated by large numbers of TNF-alpha-positive monocytes, and concomitant TNF-alpha plasma levels were elevated compared with uncomplicated controls. In marked contrast IL-1-beta production by macrophages and vascular and sinus endothelial cells was restricted to the most severe, irreversible rejection episodes. The localization of cytokine-positive cells coincided with areas of maximum induction of ICAM-1 and von Willebrand Factor. In chronic graft dysfunction increased numbers of mature macrophages were found. A large proportion of these were positive for TNF-alpha as well as IL-1-beta. Distinct from acute rejection episodes, however, parallel TNF-alpha plasma levels were not elevated, suggesting cytokine storage rather than secretion. The present results indicate an important local role of TNF-alpha and IL-1-beta in the early phase of the rejection process. They presumably activate endothelial cells to upregulate the expression of adhesion molecules, thereby facilitating mononuclear cell adhesion and extravasation. Therefore, specific inactivation of cytokines or of their actions may prove to be a powerful tool in the prevention and treatment of allograft rejection in the future.

Transplantation of H-2Kb-transgenic adrenocortical cells in the mouse having undergone an adrenalectomy: functional and morphological aspects.

BACKGROUND: A new model of cellular adrenocortical transplantation after bilateral adrenalectomy in the mouse was established. This model was used to study the effects of the expression of the transgenic MHC class I molecule H-2K(b) (Kb) on graft survival and morphologic features, corticosterone secretion, and the possibility of tolerance induction in the recipient. METHOD: A single cell suspension of purified adrenocortical cells was grafted under the kidney capsule of B10.Br (H-2k) mice having adrenalectomies. Syngeneic, fully MHC-mismatched, and MHC class I-incompatible Kb-transgenic mice served as donor strains. To analyze graft function, urinary excretion and serum levels of corticosterone were monitored over 100 days. Tolerance induction in the graft recipients of Kb-transgenic and third party skin grafts was tested on day 50 after adrenocortical transplantation. Histological sections of the adrenocortical grafts were obtained on day 100. RESULTS: Recipients of syngeneic and Kb-transgenic grafts displayed pretransplant corticosterone levels on days 20, 50, and 100 and ACTH-stimulated serum corticosterone levels similar to those of controls on day 100 after adrenocortical transplantation. In contrast, in recipients of fully MHC-mismatched grafts, corticosterone excretion was significantly reduced. In this group, 4 of 7 mice did not survive. Syngeneic skin grafts survived indefinitely in recipients of syngeneic and Kb-transgenic adrenocortical grafts, whereas Kb-transgenic and fully MHC-mismatched skin grafts were acutely rejected. Tissue sections of the adrenocortical grafts revealed vascularized cell conglomerates in syngeneic and Kb-transgenic grafts without infiltrations of mononuclear cells. Furthermore, a differentiation similar to adrenocortical organization was partly found. CONCLUSION: In conclusion, a model of cellular adrenocortical transplantation was established. The results show that syngeneic transplantation resulted in physiological corticosterone levels early after transplantation, whereas fully MHC-incompatible grafts were rejected. Recipients of Kb-transgenic grafts showed unimpaired adrenocortical function, but did not tolerize toward Kb-transgenic skin grafts. Possible mechanisms include a local immunomodulatory effect of glucocorticoids secreted by the graft and a low immunogenicity of the relatively small numbers of transplanted cells.

Ligand density determines the efficiency of negative selection in the thymus.

To study the influence of antigen density on the efficiency of negative selection in the thymus, MHC class I (H-2K(b), K(b)) transgenic mice were generated, which expressed a K(b) transgene under the control of its natural promoter at 33% (K(b-lo)) or 150% (K(b-hi)) the surface density of Kb in C57BL/6 (B6, H-2(b)) mice. These mice were crossed to anti-K(b) T-cell receptor (Des-TCR) transgenic mice. In Des-TCRxK(b-hi) double transgenic mice, Des-TCR bearing T cells were completely eliminated during thymocyte maturation. In contrast, in Des-TCRxK(b-lo) double transgenic mice, two populations of Des-TCR T cells were evident, which either expressed the Des-TCR at intermediate density in the absence of CD8 (Des-TCR(int)CD8(-)) or expressed both the Des-TCR and CD8 at low density (Des-TCRloCD8lo). In the thymus of both types of double transgenic mice, no Des-TCR(+)CD4(+)CD8(+) thymocytes were detected, suggesting that deletion of Des-TCR cells occurred before the CD4(+)CD8(+) stage. Because only very few Des-TCR(+) thymocytes were found in Des-TCRxK(b-hi) transgenic mice, deletion of these T cells apparently occurred upon expression of the Des-TCR. By contrast, Des-TCRxK(b-lo) transgenic mice showed distinct populations of Des-TCR(int)CD4-8- and Des-TCR(lo)CD8(lo) thymocytes, suggesting that expression of the CD8 coreceptor was required to allow negative selection to proceed. Functional analyses showed that sublethally irradiated Des-TCRxK(b-lo) double transgenic mice were protected from lethal graft-versus-host disease by injected Des-TCR lymph node cells.

Improvement of acute and chronic renal dysfunction in liver transplant patients after substitution of calcineurin inhibitors by mycophenolate mofetil.

BACKGROUND: Renal dysfunction caused by treatment with the calcineurin inhibitors (CNI) is a major problem in the long-term course after liver transplantation. PATIENTS: In 22 liver graft recipients with renal dysfunction and stable graft function between 3 weeks and 12 years after transplantation, CNI were substituted by MMF at a final dose of 1.5-3 g/day between October 1996 and October 1998. METHODS: In a prospective non-randomized study, the development of renal function, the side effects of MMF medication, and the stability of liver function were analyzed for a mean follow-up of 15 months. Results. (1) MMF was withdrawn in four patients for major side effects between 1 and 7 months after study entry; eight patients had minor side effects. (2) Six months after study entry, renal function had improved in 17 of the 22 study patients; mean serum creatinine +/-SD (micromol/L) was 201+/-77 at entry and 153+/-65 after 3 months (P<0.001). (3) Improvement occurred in 11 of 15 patients with creatinine elevation > or =12 months and in 6 of 6 patients with creatinine elevation < or =6 months. (4) One patient developed transient liver dysfunction and a second required retransplantation for progressive cholestasis but without signs of rejection. CONCLUSIONS: In patients who undergo liver transplantation, substitution of CNI by MMF leads to improvement of acute as well as chronic renal dysfunction in most cases. Side effects of MMF may be limiting in some patients, and the immunological consequences remain to be studied.

A murine model of allogeneic adrenocortical cell transplantation: perspectives for the treatment of Addison's disease in humans.

BACKGROUND: Hormone substitution for the treatment of adrenocortical insufficiency (Addison's disease) does not adequately substitute the hormone peaks required in stress situations. Therefore, allogeneic transplantation of adrenal cortex could offer an intriguing alternative. METHODS: Major histocompatibility complex (MHC) class I transgenic mice were used for the implementation of an animal model of adrenocortical cell transplantation in adrenalectomized mice. K(b)-transgenic cells and allogeneic adrenocortical cells were cocultured in mixed lymphocyte cultures to examine the alloimmune response. Lymphocytes from T-cell receptor transgenic mice and normal allogeneic mice served as responder cells. The effect of corticosteroids secreted by adrenocortical cells was antagonized by the steroid receptor antagonist mifepristone (RU486). RESULTS: In vitro coculture experiments showed that MHC class I disparate adrenocortical cells failed to activate B10.BR and T-cell receptor transgenic lymph node cells. In the presence of mifepristone this inhibitory effect was antagonized, resulting in strong lymphocyte proliferation. Activation of B10.BR lymphocytes by K(b)-disparate spleen cells was also abolished in the presence of adrenocortical cells. This effect, however, could not be reversed by mifepristone. CONCLUSIONS: In vitro, the presence of adrenocortical cells potently suppressed allogeneic immune responses. This effect was only in part due to the secretion of corticosteroids, pointing to an additional immunomodulatory property of adrenocortical cells.

Prevention of delayed gastric emptying after pylorus-preserving pancreatoduodenectomy with antecolic reconstruction, a long jejunal loop, and a jejuno-jejunostomy.

BACKGROUND: Delayed gastric emptying (DGE) is one of the major complications following pylorus-preserving pancreatoduodenectomy (PPPD). It leads to significant patient distress and prolonged hospitalization and therefore increased treatment costs. DGE etiology remains unclear but seems to be multifactorial. In order to decrease DGE rates, reconstruction methods have been modified. The presented retrospective study was to evaluate outcomes of different surgical techniques at our institution with special emphasis on retrocolic and antecolic reconstruction types. MATERIAL AND METHODS: One hundred thirteen consecutive patients underwent PPPD between September 2004 and December 2011 for periampullary and bile duct lesions of the pancreatic head and the papilla of Vater. These patients were reviewed for DGE occurrence and other factors. Four different types of reconstruction were applied: the classic retrocolic reconstruction using a short jejunal loop (short loop, n = 40) and three types of reconstructions using a long loop: one with a long loop and retrocolic duodenojejunostomy (n = 22), another with a long loop and an additional latero-lateral enterostomy (Braun's anastomosis, n = 23), and finally, an antecolic group with Braun's anastomosis (n = 28). Patients were reviewed for DGE incidence and severity following the International Study Group of Pancreatic Surgery definition of DGE. RESULTS: The highest DGE occurrence was noted in the retrocolic group using a short jejunal loop (15 of 32 patients, 46.9%), whereas the reconstruction types using long loops showed a notable decrease: DGE occurred in 4 of 16 patients (25%) in the retrocolic group, in 6 of 21 patients (28.6%) in the retrocolic group with an additional latero-lateral enterostomy (Braun's anastomosis), and finally, only 1 of 22 patients (4.5%, p = 0.009) in the antecolic group with Braun's anastomosis presenting with DGE, grade A. However, neither hospitalization time nor days in the intensive care unit were significantly different. There was no difference in DGE rates between the retrocolic long-loop groups with and without Braun's anastomosis. CONCLUSION: The results of this retrospective study suggest that the antecolic route with a long jejunal loop and Braun's anastomosis minimizes DGE rates.

[Surgical management of a retrorectal tumor with consideration of a rare differential diagnosis]. / Management eines retrorektalen Tumors unter Berücksichtigung einer seltenen Differenzialdiagnose.

We present a case of a retrorectal space occupying lesion diagnosed as an adenocarcinoma of unknown primary origin by preoperative histopathology. Localization slightly above the anal sphincter would have required extirpation of the rectum. Rectal palpation, endosonography and radiological imaging, however, suggested a retrorectal tumor or a metastasis of an adenocarcinoma. Both entities would have required local resection. We applied a surgical algorithm including frozen biopsy allowing a stepwise choice of operative procedure from the spectrum in question. The operation performed was thus tailored to the entity of the tumor.

[Incarcerated Spieghel-Hernie mimicking an acute exacerbation of Crohn's disease]. / "Akute Exazerbation des Morbus Crohn" erweist sich sonographisch als inkarzerierte Spieghel-Hernie.

We report on a 25-year-old woman with long-standing Crohn's disease. Upon admittance to the emergency department, the patient complained of abdominal pain with increasing intensity over the last few days. Clinical examination revealed an abdominal mass in the right lower quadrant, and blood tests showed elevated markers of inflammation. Surprisingly, abdominal ultrasound did not show the suspected complication of Crohn's disease, but rather an incarcerated abdominal wall hernia, which turned out to be a spigelian hernia upon surgical repair. This case stresses the importance of abdominal ultrasound to rule out other diagnoses in patients with chronic inflammatory bowel disease in the emergency setting before starting a potentially dangerous treatment with high-dose steroids.