Patient-reported outcomes at three months after pancreatic surgery for benign and malignant diseases - A prospective observational study.

BACKGROUND/OBJECTIVES: Pancreatic surgery may have a long-lasting effect on patients' health status and quality of life (QoL). We aim to evaluate patient-reported outcomes (PRO) 3 months after pancreatic surgery. METHODS: Patients scheduled for pancreatic surgery were enrolled in a prospective trial at five German centers. Patients completed PRO questionnaires (EQ-5D-5L, EORTC QLQ-PAN26, patient-reported happiness, and HADS-D), we report the first follow-up 3 months after surgery as an interim analysis. Statistical testing was performed using R software. RESULTS: From 2019 to 2022 203 patients were enrolled, a three-month follow-up questionnaire was available in 135 (65.5 %). 77 (57.9 %) underwent surgery for malignant disease. Patient-reported health status (EQ-5D-5L) was impaired in 4/5 dimensions (mobility, self-care, usual activities, pain, discomfort) for patients with malignant and 3/5 dimensions (mobility, self-care, usual activities) for patients with benign disease 3 months after surgery (p < 0.05). Patients with malignant disease reported an increase in depressive symptoms, patients with benign disease had a decrease in anxiety symptoms (HADS-D; depression: 5.00 vs 6.51, p = 0.002; anxiety: 8.04 vs. 6.34, p = 0.030). Regarding pancreatic-disease-specific symptoms (EORTC-QLQ-PAN26), patients with malignant disease reported increased problems with taste, weight loss, weakness in arms and legs, dry mouth, body image and troubling side effects at three months. Patients with benign disease indicated more weakness in arms and legs, troubling side effects but less future worries at three months. CONCLUSION: Patient-reported outcomes of patients undergoing pancreatic surgery for benign vs. malignant disease show important differences. Patients with malignant tumors report more severely decreased quality of life 3 months postoperatively than patients with benign tumors.

SOCIUS Mentoring-A Novel Course to Encourage Students for a Career as Surgical Oncologists.

Surgical disciplines are affected by an increasing shortage of young doctors. Studies show that formerly interested students decide against a career in surgical disciplines at the end of their studies or during practical year. Measures to counteract this development are urgently needed. As a joint project between gynecology, urology, and general surgery, SOCIUS mentoring was designed to prepare and encourage students for a career in surgical oncology. The structured curriculum of SOCIUS mentoring contains six modules, including surgical skills, soft skills, mentoring, theory, clinical visitation, and congress participation and runs over one year. Effects on confidence towards physician skills and plans for a future career were evaluated with questionnaires. After participation, students reported increased confidence in surgical and soft skills. In addition, participants noted that they have specified their career goals and gained more confidence in surgery, as well as seeing more development potential for a career in surgery. We describe the implementation of a novel extracurricular program for motivated students that combines individual mentoring with surgical and soft skills training. Due to its modular structure, this concept can easily be transferred to other disciplines. SOCIUS mentoring, with its combination of mentoring and skills training, is a promising measure to prepare and motivate students for their surgical career and thus counteract the shortage of young talent.

Antibiotic-Resistant Bacteria Colonizing the Bile Duct Are Associated with Increased Morbidity and Mortality after Resection of Extrahepatic Cholangiocarcinoma.

Background: Patients with extrahepatic cholangiocarcinoma (CCA) face considerable morbidity including septic complications after surgery. The aim of this study was to characterize the bacterial spectrum of the common hepatic duct (CHD) and its clinical relevance regarding morbidity and mortality after resection of extrahepatic CCA. Methods: We retrospectively analyzed data from 205 patients undergoing surgery for extrahepatic CCA in our department between January 2000 and March 2015. Patients were reviewed for pre-operative medical conditions, biliary bacterial flora obtained from intra-operative swabs, different septic complications, and post-operative outcome. Results: Bacterial colonization of the CHD was observed in 84.9% of the patients, with Enterococcus faecalis being detected most frequently (28.3%). Wound infections occurred in 30.7% of patients. Bacterial flora of the CHD and of the post-operatively colonized wounds coincided in 51.5% and of intra-abdominal swabs obtained during surgical revisions in 40.0%. Ciprofloxacin-resistant bacteria in the CHD were identified as independent risk factor for wound infections (odds ratio [OR], 3.330; 95% confidence interval [CI], 1.771-6.263; p < 0.001) and for complications requiring surgical revision (OR, 2.417; 95% CI, 1.288-4.539; p = 0.006). Most important independent risk factors for intra-hospital mortality were ampicillin-sulbactam-resistant bacteria in the CHD (OR, 3.969; 95% CI, 1.515-10.399; p = 0.005) and American Society of Anesthesiologists (ASA) grading >2 (OR, 2.936; 95% CI, 1.337-6.451; p = 0.007). Conclusions: Antibiotic-resistant bacteria from the CHD are associated with increased morbidity and mortality in patients undergoing resection for extrahepatic CCA.

Increase of α-dicarbonyls in liver and receptor for advanced glycation end products on immune cells are linked to nonalcoholic fatty liver disease and liver cancer.

Hepatocellular carcinoma (HCC) is the most common primary malignancy of the liver with a very poor prognosis and constantly growing incidence. Among other primary risks of HCC, metabolic disorders and obesity have been extensively investigated over recent decades. The latter can promote nonalcoholic fatty liver disease (NAFLD) leading to the inflammatory form of nonalcoholic steatohepatitis (NASH), that, in turn, promotes HCC. Molecular determinants of this pathogenic progression, however, remain largely undefined. In this study, we have focussed on the investigation of α-dicarbonyl compounds (α-dC), highly reactive and tightly associated with overweight-induced metabolic disorders, and studied their potential role in NAFLD and progression toward HCC using murine models. NAFLD was induced using high-fat diet (HFD). Autochthonous HCC was induced using transposon-based stable intrahepatic overexpression of oncogenic NRASG12V in mice lacking p19Arf tumor suppressor. Our study demonstrates that the HFD regimen and HCC resulted in strong upregulation of α-dC in the liver, heart, and muscles. In addition, an increase in α-dC was confirmed in sera of NAFLD and NASH patients. Furthermore, higher expression of the receptor for advanced glycation products (RAGE) was detected exclusively on immune cells and not on stroma cells in livers of mice with liver cancer progression. Our work confirms astable interplay of liver inflammation, carbonyl stress mediated by α-dC, and upregulated RAGE expression on CD8+ Tand natural killer (NK) cells in situ in NAFLD and HCC, as key factors/determinants in liver disease progression. The obtained findings underline the role of α-dC and RAGE+CD8+ Tand RAGE+ NK cells as biomarkers and candidates for a local therapeutic intervention in NAFLD and malignant liver disease.

Transcriptome Profiling Identifies TIGIT as a Marker of T-Cell Exhaustion in Liver Cancer.

BACKGROUND AND AIMS: Programmed death 1 (PD-1) checkpoint inhibition has shown promising results in patients with hepatocellular carcinoma, inducing objective responses in approximately 20% of treated patients. The roles of other coinhibitory molecules and their individual contributions to T-cell dysfunction in liver cancer, however, remain largely elusive. APPROACH AND RESULTS: We performed a comprehensive mRNA profiling of cluster of differentiation 8 (CD8) T cells in a murine model of autochthonous liver cancer by comparing the transcriptome of naive, functional effector, and exhausted, tumor-specific CD8 T cells. Subsequently, we functionally validated the role of identified genes in T-cell exhaustion. Our results reveal a unique transcriptome signature of exhausted T cells and demonstrate that up-regulation of the inhibitory immune receptor T-cell immunoreceptor with immunoglobulin and immunoreceptor tyrosine-based inhibitor motif domains (TIGIT) represents a hallmark in the process of T-cell exhaustion in liver cancer. Compared to PD-1, expression of TIGIT more reliably identified exhausted CD8 T cells at different stages of their differentiation. In combination with PD-1 inhibition, targeting of TIGIT with antagonistic antibodies resulted in synergistic inhibition of liver cancer growth in immunocompetent mice. Finally, we demonstrate expression of TIGIT on tumor-infiltrating CD8 T cells in tissue samples of patients with hepatocellular carcinoma and intrahepatic cholangiocarcinoma and identify two subsets of patients based on differential expression of TIGIT on tumor-specific T cells. CONCLUSIONS: Our transcriptome analysis provides a valuable resource for the identification of key pathways involved in T-cell exhaustion in patients with liver cancer and identifies TIGIT as a potential target in checkpoint combination therapies.

Preoperative leukocytosis and the resection severity index are independent risk factors for survival in patients with intrahepatic cholangiocarcinoma.

PURPOSE: The incidence of intrahepatic cholangiocarcinoma is increasing worldwide. Despite advances in surgical and non-surgical treatment, reported outcomes are still poor and surgical resection remains to be the only chance for long-term survival of affected patients. The identification and validation of prognostic factors and scores, such as the recently introduced resection severity index, for postoperative morbidity and mortality are essential to facilitate optimal therapeutic regimens. METHODS: This is a retrospective analysis of 269 patients undergoing resection of histologically confirmed intrahepatic cholangiocarcinoma between February 1996 and September 2018 at a tertiary referral center for hepatobiliary surgery. Regression analyses were performed to evaluate potential prognostic factors, including the resection severity index. RESULTS: Median postoperative follow-up time was 22.93 (0.10-234.39) months. Severe postoperative complications (≥ Clavien-Dindo grade III) were observed in 94 (34.9%) patients. The body mass index (p = 0.035), the resection severity index (ASAT in U/l divided by Quick in % multiplied by the extent of liver resection graded in points; p = 0.006), additional hilar bile duct resection (p = 0.005), and number of packed red blood cells transfused during operation (p = 0.036) were independent risk factors for the onset of severe postoperative complications. Median Kaplan-Meier survival after resection was 27.63 months. Preoperative leukocytosis (p = 0.003), the resection severity index (p = 0.005), multivisceral resection (p = 0.001), and T stage ≥ 3 (p = 0.013) were identified as independent risk factors for survival. CONCLUSION: Preoperative leukocytosis and the resection severity index are useful variables for preoperative risk stratification since they were identified as significant predictors for postoperative morbidity and mortality, respectively.

Abdominal Surgery in Patients with Ventricular Assist Devices: a Single-Center Report.

This study was performed to evaluate the incidence and outcome of patients with ventricular assist devices (VADs) undergoing abdominal surgery at our institution. A total of 604 adult patients who underwent VAD implantation between February 2004 and February 2018 were analyzed retrospectively with a median follow-up time of 66 (6-174) months. Thirty-nine patients (6.5%) underwent abdominal surgery. Elective surgical procedures were performed in 22 patients (56.4%), mainly for abdominal wall hernia repairs, partial colectomies, and cholecystectomies. Early after elective abdominal surgery no patient died, resulting in a median survival of 23 (1-78) months. Emergency surgery was performed in 17 patients (43.6%). The most common emergency indications were intestinal ischemia and/or perforation. Eight patients undergoing emergent surgery (44.4%) died within the first 30 days after primary abdominal operation, mainly due to sepsis and consecutive multiple organ failure, resulting in a dismal median survival of one month (0-52). Patients undergoing abdominal surgery had significantly lower rates of realized heart-transplantation (p = 0.031) and a significantly higher rate of VAD exchange, before or after abdominal surgery, due to thromboses or infections (p = 0.037). Nonetheless, overall survival after primary VAD implantation in these patients (median 38 months; 0-107) was not significantly impaired when compared to all other patients undergoing VAD implantation (median 30 months; 0-171). In summary, elective abdominal surgery can be performed safely when well planned by an experienced multidisciplinary team. Abdominal complications in VAD patients requiring emergent surgery, however, lead to a significant increase in short-term morbidity and a high 30-day mortality rate.

The importance of MHC class II in allogeneic bone marrow transplantation and chimerism-based solid organ tolerance in a rat model.

Mixed hematopoietic chimerism enables donor-specific tolerance for solid organ grafts. This study evaluated the influence of different serological major histocompatibility complex disparities on chimerism development, graft-versus-host disease incidence and subsequently on solid organ tolerance in a rat model. For bone marrow transplantation conditioning total body irradiation was titrated using 10, 8 or 6 Gray. Bone marrow transplantation was performed across following major histocompatibility complex mismatched barriers: complete disparity, MHC class II, MHC class I or non-MHC mismatch. Recipients were clinically monitored for graft-versus-host disease and analyzed for chimerism using flow cytometry. After a reconstitution of 100 days, composition of peripheral leukocytes was determined. Mixed chimeras were challenged with heart grafts from allogeneic donor strains to define the impact of donor MHC class disparities on solid organ tolerance on the basis of stable chimerism. After myeloablation with 10 Gray of total body irradiation, chimerism after bone marrow transplantation was induced independent of MHC disparity. MHC class II disparity increased the incidence of graft-versus-host disease and reduced induction of stable chimerism upon myelosuppressive total body irradiation with 8 and 6 Gray, respectively. Stable mixed chimeras showed tolerance towards heart grafts from donors with MHC matched to either bone marrow donors or recipients. Isolated matching of MHC class II with bone marrow donors likewise led to stable tolerance as opposed to matching of MHC class I. In summary, MHC class II disparity was critically associated with the onset of graft-versus host disease and was identified as obstacle for successful development of chimerism after bone marrow transplantation and subsequent donor-specific solid organ tolerance.

An Immunological Model for Heterotopic Heart and Cardiac Muscle Cell Transplantation in Rats.

Heterotopic heart transplantation in rats has been a commonly used model for diverse immunological studies for more than 50 years. Several modifications have been reported since the first description in 1964. After 30 years of performing heterotopic heart transplantation in rats, we have developed a simplified surgical approach, which can be easily taught and performed without further surgical training or background. After dissection of the ascending aorta and the pulmonary artery and ligation of superior and inferior caval and pulmonary veins, the donor heart is harvested and subsequently perfused with ice-cold saline solution supplemented with heparin. After clamping and incising the recipient abdominal vessels, the donor ascending aorta and pulmonary artery are anastomosed to the recipient abdominal aorta and inferior vena cava, respectively, using continuous running sutures. Depending on different donor-recipient combinations, this model allows analyses of either acute or chronic rejection of allografts. The immunological significance of this model is further enhanced by a novel approach of in-ear injection of vital cardiac muscle cells and subsequent analysis of draining cervical lymphatic tissue.

Potent Antitumor Activity of Liposomal Irinotecan in an Organoid- and CRISPR-Cas9-Based Murine Model of Gallbladder Cancer.

Gallbladder cancer is associated with a dismal prognosis, and accurate in vivo models will be elemental to improve our understanding of this deadly disease and develop better treatment options. We have generated a transplantation-based murine model for gallbladder cancer that histologically mimics the human disease, including the development of distant metastasis. Murine gallbladder-derived organoids are genetically modified by either retroviral transduction or transfection with CRISPR/Cas9 encoding plasmids, thereby allowing the rapid generation of complex cancer genotypes. We characterize the model in the presence of two of the most frequent oncogenic drivers-Kras and ERBB2-and provide evidence that the tumor histology is highly dependent on the driver oncogene. Further, we demonstrate the utility of the model for the preclinical assessment of novel therapeutic approaches by showing that liposomal Irinotecan (Nal-IRI) is retained in tumor cells and significantly prolongs the survival of gallbladder cancer-bearing mice compared to conventional irinotecan.

Alloresponses of Mixed Lymphocyte Hepatocyte Culture to Immunosuppressive Drugs as an In-Vitro Model of Hepatocyte Transplantation.

BACKGROUND Hepatocyte transplantation (HCTx) has the potential for the treatment of end-stage liver disease. However, failure of engraftment and the long-term acceptance of cellular allografts remain significant challenges for its clinical application. The aim of this study was to investigate the efficacy of the immunosuppressive agents, Cyclosporine, Everolimus, and Belatacept to suppress the alloresponse of primary human hepatocytes in a mixed lymphocyte-hepatocyte culture (MLHC) and their potential hepatotoxicity in vitro. MATERIAL AND METHODS Primary human hepatocytes were co-cultured with allogeneic peripheral blood mononuclear cells (PBMCs) in an MLHC. Proliferative alloresponses were determined by flow cytometry, and cytokine secretion was measured using Luminex-based multiplex technology. Using an MLHC, the alloresponses of primary human hepatocytes were compared in the presence and absence of Cyclosporine, Everolimus, and Belatacept. Cultured primary human hepatocytes were assessed for the production of albumin, urea, aspartate transaminase (AST) and DNA content. Metabolic activity was determined with the MTT assay. RESULTS Immune responses induced by primary human hepatocytes were effectively suppressed by Cyclosporine, Everolimus, and Belatacept. Everolimus significantly reduced the metabolic activity of primary human hepatocytes in vitro, suggesting impairment of cell viability. However, further functional analysis showed no significant differences between treated and untreated controls. CONCLUSIONS Cyclosporine, Everolimus, and Belatacept suppressed the alloresponse of primary human hepatocytes in an MLHC without significant cytotoxicity or functional cell impairment.

Recipient natural killer cells alter the course of rejection of allogeneic heart grafts in rats.

Rejection of solid organ grafts is regarded to be dependent on T cell responses. Nonetheless, numerous studies have focused on the contribution of NK cells in this process, resulting in contradictory theories. While some conclude that there is no participation of NK cells, others found an inflammatory or regulative role of NK cells. However, the experimental settings are rarely comparable with regard to challenged species, strain combinations or the nature of the graft. Thus, clear definition of NK cell contribution might be impeded by these circumstances. In this study we performed heterotopic heart transplantation (HTx) in rats, choosing one donor-recipient-combination leading to a fast and a second leading to a prolonged course of graft rejection. We intervened in the rejection process, by depletion of recipient NK cells on the one hand and by injection of activated NK cells syngeneic to the recipients on the other. The fast course of rejection could not be influenced by any of the NK cell manipulative treatments. However, the more prolonged course of rejection was highly susceptible to depletion of NK cells, resulting in significant acceleration of rejection, while injection of NK cells induced acceptance of the grafts. We suggest that, depending on the specific setting, NK cells can attenuate the first trigger of immune response, which allows establishing the regulatory activity leading to tolerance of the graft.

Protein kinase C beta deficiency increases glucose-mediated peritoneal damage via M1 macrophage polarization and up-regulation of mesothelial protein kinase C alpha.

BACKGROUND: Peritoneal membrane (PM) damage during peritoneal dialysis (PD) is mediated largely by high glucose (HG)-induced pro-inflammatory and neo-angiogenic processes, resulting in PM fibrosis and ultrafiltration failure. We recently demonstrated a crucial role for protein kinase C (PKC) isoform α in mesothelial cells. METHODS: In this study we investigate the role of PKCß in PM damage in vitro using primary mouse peritoneal macrophages (MPMΦ), human macrophages (HMΦ) and immortalized mouse peritoneal mesothelial cells (MPMCs), as well as in vivo using a chronic PD mouse model. RESULTS: We demonstrate that PKCß is the predominant classical PKC isoform expressed in primary MPMΦ and its expression is up-regulated in vitro under HG conditions. After in vitro lipopolysaccharides stimulation PKCß-/- MPMΦ demonstrates increased levels of interleukin 6 (IL-6), tumour necrosis factor α, and monocyte chemoattractant protein-1 and drastically decrease IL-10 release compared with wild-type (WT) cells. In vivo, catheter-delivered treatment with HG PD fluid for 5 weeks induces PKCß up-regulation in omentum of WT mice and results in inflammatory response and PM damage characterized by fibrosis and neo-angiogenesis. In comparison to WT mice, all pathological changes are strongly aggravated in PKCß-/- animals. Underlying molecular mechanisms involve a pro-inflammatory M1 polarization shift of MPMΦ and up-regulation of PKCα in MPMCs of PKCß-/- mice. Finally, we demonstrate PKCß involvement in HG-induced polarization processes in HMΦ. CONCLUSIONS: PKCß as the dominant PKC isoform in MPMΦ is up-regulated by HG PD fluid and exerts anti-inflammatory effects during PD through regulation of MPMΦ M1/M2 polarization and control of the dominant mesothelial PKC isoform α.

Hepatocyte-induced CD4+ T cell alloresponse is associated with major histocompatibility complex class II up-regulation on hepatocytes and suppressible by regulatory T cells.

Hepatocyte transplantation is a promising therapeutic approach for various liver diseases. Despite the liver's tolerogenic potential, early immune-mediated loss of transplanted cells is observed, and longterm acceptance has not been achieved yet. Patients deemed tolerant after liver transplantation presented an increased frequency of regulatory T cells (Tregs), which therefore also might enable reduction of posttransplant cell loss and enhance longterm allograft acceptance. We hence characterized hepatocyte-induced immune reactions and evaluated the immunomodulatory potential of Tregs applying mixed lymphocyte cultures and mixed lymphocyte hepatocyte cultures. These were set up using peripheral blood mononuclear cells and primary human hepatocytes, respectively. Polyclonally expanded CD4+ CD25high CD127low Tregs were added to cocultures in single-/trans-well setups with/without supplementation of anti-interferon γ (IFNγ) antibodies. Hepatocyte-induced alloresponses were then analyzed by multicolor flow cytometry. Measurements indicated that T cell response upon stimulation was associated with IFNγ-induced major histocompatibility complex (MHC) class II up-regulation on hepatocytes and mediated by CD4+ T cells. An indirect route of antigen presentation could be ruled out by use of fragmented hepatocytes and culture supernatants of hepatocytes. Allospecific proliferation was accompanied by inflammatory cytokine secretion. CD8+ T cells showed early up-regulation of CD69 despite lack of cell proliferation in the course of coculture. Supplementation of Tregs effectively abrogated hepatocyte-induced alloresponses and was primarily cell contact dependent. In conclusion, human hepatocytes induce a CD4+ T cell alloresponse in vitro, which is associated with MHC class II up-regulation on hepatocytes and is susceptible to suppression by Tregs. Liver Transplantation 24 407-419 2018 AASLD.

Early Tracheostomy Reduces Time of Mechanical Ventilation in Respiratory High-Risk Patients After Liver Transplant.

OBJECTIVES: Weaning from mechanical ventilation after liver transplant can be demanding. In selected cases, tracheostomy is helpful. The optimal timing for tracheostomy in ventilator-dependent liver transplant recipients is not well known. MATERIALS AND METHODS: We retrospectively analyzed data of 447 patients who had undergone liver transplant in our hospital. Thirty-nine patients who had high risk of prolonged mechanical ventilation according to the Respiratory Risk Score were identified from 95 patients who received tracheostomy after liver transplant. RESULTS: When compared with tracheostomy performed > 3 days after transplant, early tracheostomy (≤ 3 days) had a higher likelihood of a brief duration of mechanical ventilation (62.5% vs 9.7%; P = .001). Accordingly, time spent in an intensive care unit was shorter with early tracheostomy. CONCLUSIONS: This study provides a retrospective analysis of a small study cohort; therefore, validation of our findings requires a prospective randomized multicenter study on early tracheostomy in respiratory high-risk liver transplant recipients.

Monitoring of liver function in a 73-year old patient undergoing 'Associating Liver Partition and Portal vein ligation for Staged hepatectomy': case report applying the novel liver maximum function capacity test.

BACKGROUND: The two-stage liver resection combining in situ liver transection with portal vein ligation, also referred to as ALPPS (Associating Liver Partition and Portal vein ligation for Staged hepatectomy), has been described as a promising method to increase the resectability of liver tumors. However, one of the most important issues regarding the safety of this procedure is the optimal timing of the second stage at the point of sufficient hypertrophy of the future liver remnant. The recently developed liver maximum function capacity test (LiMAx) can be applied to monitor the liver function postoperatively and hence could be a useful tool for decision-making regarding the timing of the second stage of ALPPS. CASE PRESENTATION: A 73-year-old female patient presented with metachronous colorectal liver metastasis comprising the complete right liver lobe as well as segment IV. Due to an insufficient future liver remnant (19.3 %; segments II and III of the liver) and a low future liver remnant:body weight ratio (0.28 %) the decision was made to perform an ALPPS-procedure in order to avoid development of postoperative small-for-size syndrome. Despite a formally sufficient increase of the FLR to 30.8 % within 7 days after the first step of ALPPS, the liver function was seen to only slowly increase as expressed by a LiMAx value of 245 µg/h/kg (baseline of 282 µg/h/kg prior to surgery). By means of the LiMAx test, sufficient increase of liver function eventually was detected by postoperative day 11 (LiMAx value of 371 µg/h/kg; FLR 35.2 %) so that the second step of ALPPS (completion of hepatectomy) was performed with no signs of liver failure during further clinical course. CONCLUSION: Performing ALPPS we have observed a significant difference between the increase in future liver remnant volume and function applying the LiMAx test. The latter tool thus might proof valuable for application in two-stage liver resection to avoid postoperative small-for-size syndrome.

Cholangitis in the postoperative course after biliodigestive anastomosis.

BACKGROUND: Hepatobiliary surgery with biliodigestive anastomosis (BDA) results in a loss of the sphincter of Oddi with consecutive ascension of bacteria into the bile system which may cause cholangitis in the postoperative course. METHODS: Patients who received reconstruction with a BDA after hepatobiliary surgery were analyzed retrospectively for their postoperative course of disease depending on intraoperatively obtained bile cultures and antibiotic prophylaxis. RESULTS: Two hundred forty-three patients were included in the analysis, 49.4 % of whom had received endoscopic stenting before the operation. Stenting was significantly associated with the presence of drug-resistant bacteria in the intraoperatively obtained bile sample (p < 0.001, OR = 4.09). Of all patients, 14.4 % developed postoperative cholangitis. This was significantly associated with the postoperative length of stay in the intensive care unit (p = 0.002, OR = 1.035). The highest incidence of postoperative cholangitis was found in patients with cholangiocellular carcinoma (n = 12, p = 0.046, OR = 2.178). Patients were more likely to harbor strains with resistance against the antibiotic that was given intraoperatively. CONCLUSION: The risk for the presence of drug-resistant bacteria is increased by preoperative stenting of the common bile duct. Bile culture by intraoperative swabs can be altered by the perioperative antibiotic prophylaxis as it induces microbiological selection in the common bile duct.

Protein kinase C α inhibition prevents peritoneal damage in a mouse model of chronic peritoneal exposure to high-glucose dialysate.

Chronic exposure to commercial glucose-based peritoneal dialysis fluids during peritoneal dialysis induces peritoneal membrane damage leading to ultrafiltration failure. In this study the role of protein kinase C (PKC) α in peritoneal membrane damage was investigated in a mouse model of peritoneal dialysis. We used 2 different approaches: blockade of biological activity of PKCα by intraperitoneal application of the conventional PKC inhibitor Go6976 in C57BL/6 wild-type mice and PKCα-deficient mice on a 129/Sv genetic background. Daily administration of peritoneal dialysis fluid for 5 weeks induced peritoneal upregulation and activation of PKCα accompanied by epithelial-to-mesenchymal transition of peritoneal mesothelial cells, peritoneal membrane fibrosis, neoangiogenesis, and macrophage and T cell infiltration, paralleled by reduced ultrafiltration capacity. All pathological changes were prevented by PKCα blockade or deficiency. Moreover, treatment with Go6976 and PKCα deficiency resulted in strong reduction of proinflammatory, profibrotic, and proangiogenic mediators. In cell culture experiments, both treatment with Go6976 and PKCα deficiency prevented peritoneal dialysis fluid-induced release of MCP-1 from mouse peritoneal mesothelial cells and ameliorated transforming growth factor-ß1-induced epithelial-to-mesenchymal transition and peritoneal dialysis fluid-induced MCP-1 release in human peritoneal mesothelial cells. Thus, PKCα plays a crucial role in the pathophysiology of peritoneal membrane dysfunction induced by peritoneal dialysis fluids, and we suggest that its therapeutic inhibition might be a valuable treatment option for peritoneal dialysis patients.

A Depleting Anti-CD45 Monoclonal Antibody as Isolated Conditioning for Bone Marrow Transplantation in the Rat.

OBJECTIVE: A monoclonal antibody (mAb) against the leukocyte common antigen CD45 (RT7 in rats) could facilitate bone marrow transplantation (BMT). This study in rats evaluates a depletive rat anti-RT7a mAb as isolated tool for BMT conditioning without using irradiation or any chemotherapeutic / immunosuppressive agent. METHODS: The model used a CD45 di-allelic polymorphism (RT7a/RT7b). The anti-RT7a mAb was intravenously administered to LEW.1W rats (RT1uRT7a) at 5, 10 and 15 mg/kg. 1x10(8) BM cells of MHC syngeneic (RT1u), MHC disparate (RT1l) or MHC haploidentical (RT1u/l) donors were transplanted. All BM donor strains carried the RT7b allele so that their CD45+ cells were not affected by the anti-RT7a mAb. Recipients were monitored for reconstitution and donor-chimerism in blood leukocytes. RESULTS: mAb dosages of 5 or 10 mg/kg were myelosuppressive, whereas 15 mg/kg was myeloablative. Multi-lineage donor-chimerism at day 100 indicated engraftment of MHC syngeneic BM after any used mAb dosage (5 mg/kg: 46+/-7%; 10 mg/kg: 62+/-5%; 15 mg/kg: 80+/-4%). MHC disparate BM resulted in autologous reconstitution after conditioning by 10 mg/kg of the mAb and caused transient chimerism ending up in death associated with aplasia after conditioning by 15 mg/kg of the mAb. MHC haploidentical BM (F1 to parental) engrafted only after conditioning by 15 mg/kg (chimerism at day 100: 78+/-7%). Abandonment of α/ß TCR+ cell depletion from BM grafts impaired the engraftment process after conditioning using 15 mg/kg of the mAb in the MHC syngeneic setting (2 of 6 recipients failed to engraft) and the MHC haploidentical setting (3 of 6 recipients failed). CONCLUSION: This depletive anti-RT7a mAb is myelosuppressive and conditions for engraftment of MHC syngeneic BM. The mAb also facilitates engraftment of MHC haploidentical BM, if a myeloablative dose is used. RT7b expressing, BM-seeded α/ß TCR+ cells seem to impair the engraftment process after myeloablative mAb conditioning.

Application of allogeneic bone marrow cells in view of residual alloreactivity: sirolimus but not cyclosporine evolves tolerogenic properties.

BACKGROUND: Application of bone marrow cells (BMC) is a promising strategy for tolerance induction, but usually requires strong depletion of the host immune system. This study evaluates the ability of immunosuppressants to evolve tolerogenic properties of BMC in view of residual alloreactivity. METHODS: The rat model used a major histocompatibility complex (MHC) class II disparate bone marrow transplantation (BMT) setting (LEW.1AR1 (RT1auu) → LEW.1AR2 (RT1aau)). Heart grafts (LEW.1WR1 (RT1uua)) were disparate for the complete MHC to recipients and for MHC class I to BMC donors. Limited conditioning was performed by total body irradiation of 6 Gy. Cyclosporine (CsA) or Sirolimus (Srl) were administered for 14 or 28 days. Transplantation of heart grafts (HTx) was performed at day 16 or at day 100 after BMT. Chimerism and changes in the T cell pool were detected by flow cytometry. RESULTS: Mixed chimeras accepted HTx indefinitely, although the composition of the regenerated T cell pool was not changed to a basically donor MHC class II haplotype. Non-chimeric animals rejected HTx spontaneously. BMC recipients, who received HTx during T cell recovery at day 16, accepted HTx only after pre-treatment with Srl, although chimerism was lost. CsA pre-treatment led to accelerated HTx rejection as did isolated application of BMC. CONCLUSION: Srl evolves tolerogenic properties of allogeneic BMC to achieve indefinite acceptance of partly MHC disparate HTx despite residual alloreactivity and in particular loss of chimerism.