Mark D. Jäger

The functional relevance of passenger leukocytes and microchimerism for heart allograft acceptance in the rat.

With an organ transplant, hematopoietic donor cells are transferred to the recipient. To study the relevance of the resulting microchimerism for allograft acceptance, we analyzed a rat model of cyclosporine-induced tolerance for strongly incompatible heart allografts. Using a monoclonal antibody that detects a donor-specific CD45 allotype (RT7a), we selectively depleted donor leukocytes at different times after transplantation (days 0 or 18). Depletion was similarly effective at both times. However, only depletion on day 0 prevented tolerance induction and was associated with severe acute or chronic graft rejection. This indicates that passenger leukocytes have an essential immunomodulatory effect on the induction phase of allograft acceptance.

Liver regeneration in a retrorsine/CCl4 – induced acute liver failure model: do bone marrow-derived cells contribute?

BACKGROUND/AIMS Adult bone marrow contains progenitors capable of generating hepatocytes. Here a new liver failure model is introduced to assess whether bone marrow-derived progeny contribute to liver regeneration after acute hepatotoxic liver failure. METHODS Retrorsine was used to inhibit endogenous hepatocyte proliferation, before inducing acute liver failure by carbon tetrachloride. Bone marrow chimeras were generated before inducing liver failure to trace bone marrow-derived cells. Therefore, CD45 and major histocompatibility complex (MHC) class I dimorphic rat models were applied. RESULTS Early after acute liver failure a multilineage inflammatory infiltrate was observed, mainly consisting of granulocytes. In long-term experiments small numbers of CD90+/CD45- cells of donor origin occurred in clusters associated with portal triads. Bone marrow cell infusion was not able to enhance liver regeneration. Cellular hypertrophy was the predominant way of liver mass regeneration in models applying retrorsine. CONCLUSIONS Retrorsine pretreatment did not affect sensitivity for carbon tetrachloride. A multilineage inflammatory infiltrate was observed in rats whether pretreated with retrorsine or not. Few donor cells co-expressing CD90 (THY 1) were present in recipient livers, which may resemble donor-derived hematopoietic progenitors or oval cells. No other donor cells within liver parenchyma were detected. This is in contrast to other cell infusion models of acute cell death.

Haematopoietic stem cells improve cardiac function after infarction without permanent cardiac engraftment

Transplantation of bone marrow derived adult stem cells (BMC) improves cardiac function after acute myocardial infarction (MI). However, the cell population mediating myocardial recovery and the fate of the transplanted cells are still controversial.

Inhibition of Autophagic Flux by Salinomycin Results in Anti-Cancer Effect in Hepatocellular Carcinoma Cells

Salinomycin raised hope to be effective in anti-cancer therapies due to its capability to overcome apoptosis-resistance in several types of cancer cells. Recently, its effectiveness against human hepatocellular carcinoma (HCC) cells both in vitro and in vivo was demonstrated. However, the mechanism of action remained unclear. Latest studies implicated interference with the degradation pathway of autophagy. This study aimed to determine the impact of Salinomycin on HCC-autophagy and whether primary human hepatocytes (PHH) likewise are affected. Following exposure of HCC cell lines HepG2 and Huh7 to varying concentrations of Salinomycin (0–10 µM), comprehensive analysis of autophagic activity using western-blotting and flow-cytometry was performed. Drug effects were analyzed in the settings of autophagy stimulation by starvation or PP242-treatment and correlated with cell viability, proliferation, apoptosis induction, mitochondrial mass accumulation and reactive oxygen species (ROS) formation. Impact on apoptosis induction and cell function of PHH was analyzed. Constitutive and stimulated autophagic activities both were effectively suppressed in HCC by Salinomycin. This inhibition was associated with dysfunctional mitochondria accumulation, increased apoptosis and decreased proliferation and cell viability. Effects of Salinomycin were dose and time dependent and could readily be replicated by pharmacological and genetic inhibition of HCC-autophagy alone. Salinomycin exposure to PHH resulted in transient impairment of synthesis function and cell viability without apoptosis induction. In conclusion, our data suggest that Salinomycin suppresses late stages of HCC-autophagy, leading to impaired recycling and accumulation of dysfunctional mitochondria with increased ROS-production all of which are associated with induction of apoptosis.

Explanted Diseased Livers – A Possible Source of Metabolic Competent Primary Human Hepatocytes

Being an integral part of basic, translational and clinical research, the demand for primary human hepatocytes (PHH) is continuously growing while the availability of tissue resection material for the isolation of metabolically competent PHH remains limited. To overcome current shortcomings, this study evaluated the use of explanted diseased organs from liver transplantation patients as a potential source of PHH. Therefore, PHH were isolated from resected surgical specimens (Rx-group; n = 60) and explanted diseased livers obtained from graft recipients with low labMELD-score (Ex-group; n = 5). Using established protocols PHH were subsequently cultured for a period of 7 days. The viability and metabolic competence of cultured PHH was assessed by the following parameters: morphology and cell count (CyQuant assay), albumin synthesis, urea production, AST-leakage, and phase I and II metabolism. Both groups were compared in terms of cell yield and metabolic function, and results were correlated with clinical parameters of tissue donors. Notably, cellular yields and viabilities were comparable between the Rx- and Ex-group and were 5.3±0.5 and 2.9±0.7×106 cells/g liver tissue with 84.3±1.3 and 76.0±8.6% viability, respectively. Moreover, PHH isolated from the Rx- or Ex-group did not differ in regards to loss of cell number in culture, albumin synthesis, urea production, AST-leakage, and phase I and II metabolism (measured by the 7-ethoxycoumarin-O-deethylase and uracil-5′-diphosphate-glucuronyltransferase activity). Likewise, basal transcript expressions of the CYP monooxygenases 1A1, 2C8 and 3A4 were comparable as was their induction when treated with a cocktail that consisted of 3-methylcholantren, rifampicin and phenobarbital, with increased expression of CYP 1A1 and 3A4 mRNA while transcript expression of CYP 2C8 was only marginally changed. In conclusion, the use of explanted diseased livers obtained from recipients with low labMELD-score might represent a valuable source of metabolically competent PHH which are comparable in viability and function to cells obtained from specimens following partial liver resection.

Quality of life following living donor nephrectomy comparing classical flank incision and anterior vertical mini-incision

In this study we focused on the quality of life and satisfaction of living kidney donors comparing traditional lumbar (LDN) and mini-incision donor nephrectomy (MIDN). From May 1996 to December 2002, 174 donor nephrectomies including 127 cases of LDN and 47 cases of MIDN were performed. Donors were evaluated using the SF-36 quality-of-life survey as well as a questionnaire dealing with donors‘ attitude towards kidney donation, financial burdens, pain, cosmetic satisfaction and duration of sick leave. Our donors achieved comparable or even higher scores in all the SF-36 categories in comparison to the general US population. Following MIDN, quality of life tended to be superior compared to that of LDN donors; however, statistical significance was reached only in one of the eight categories. Duration of sick leave following surgery was in favor of MIDN compared to LDN donors. Statistically significant differences favoring MIDN were observed regarding postoperative hospital stay and cosmetic satisfaction. The procedure would be again undergone by 94 of LDN and 97% of MIDN donors. Open-donor nephrectomy is a safe and cost-effective procedure. Introduction of the here-described MIDN has led to comparable or even improved results compared to LDN.

Surgery and radioablation therapy combined: introducing a 1-week-condensed procedure bonding total thyroidectomy and radioablation therapy with recombinant human TSH

OBJECTIVE The objective of this study was to determine whether the use of recombinant human TSH (rhTSH) to stimulate radioiodine uptake after thyroidectomy is as efficacious as a period of withholding thyroid hormones, while at the same time avoiding hypothyroidism, reducing sick leave time and shortening the hospital stay. DESIGN Our aim was to compare the standard procedure of differentiated thyroid cancer treatment, which consists of thyroidectomy followed by 4 weeks of hypothyroidism and a conclusive ablative activity of (131)iodine, with a new shortened treatment in which l-thyroxine (T(4)) medication is initiated a day after thyroidectomy, followed by application of rhTSH stimulation and subsequent ablation a few days after surgery. We presumed our treatment to represent the most sophisticated strategy for the reduction in sick leave days overall without any reduction in safety or the efficacy of ablative therapy. METHODS Patients (n=25) were randomized either for surgery and rhTSH stimulation or surgery and l-T(4) abstinence before the first application of radioiodine. Ablation success was determined by neck ultrasound and serum thyroglobulin during follow-up. RhTSH receivers were monitored for an average of 635 days (s.d.+/-289) and patients in l-T(4) abstinence for an average of 624 days (s.d.+/-205). Both groups were statistically compared for significant differences in treatment efficacy, safety and overall time of sick leave. RESULTS AND CONCLUSIONS Our shortened treatment proved to be equally efficacious and safe in comparison with the conventional therapy regimen. At the same time, it showed economic advantages through the reduction in average sick leave time from approximately 29 days (l-T(4) abstinence) down to approximately 6 days (rhTSH stimulation) as well as sustaining the patients quality of life by the complete avoidance of hypothyroidism.

Surgical treatment for intrahepatic cholangiocarcinoma in Europe : a single center experience

Intrahepatic cholangiocarcinoma is the second most common primary liver tumor. The aim of this study was to analyze retrospectively the outcome of surgical treatment and prognostic factors. Clinical, histopathological and treatment data of 221 patients treated from 1995 to 2010 at our institution were investigated. Univariate and multivariate analysis of the patients data was performed. Patients after R0 and R1 resection presented an overall survival of 67% and 54.5% after 1 year and 40% and 36.4% after 3 years, respectively. The survival of patients without resection of the tumor was dismal with 26% and 3.4% after 1 and 3 years, respectively. Survival after resection was not statistically different in cases with R0 versus R1 resection (P = 0.639, log rank). Univariate Cox regression revealed that higher T stages are a significant hazard for survival (P = 0.048, hazard ratio (HR): 1.211, 95% confidence interval (CI): 1.002–2.465). Patients with tumor recurrence had a significantly inferior long‐term survival when compared to patients without recurrence (P < 0.001, log rank). Presence of lymph node metastasis (N1) was an independent prognostic factor for survival after resection in risk‐adjusted multivariate Cox regression (P < 0.001, HR: 2.577, 95% CI: 1.742–3.813). Adjuvant chemotherapy did not improve patient survival significantly (P = 0.550, log rank). Surgical resection is still the best treatment option for intrahepatic cholangiocarcinoma regarding the patients long‐term survival. R0 and R1 resection enable both better survival rates when compared to surgical exploration without resection. T status, N status, and tumor recurrence seem to be the most important prognostic factors after resection.

Bone marrow aplasia induced by passenger leukocytes from heart allografts

OBJECTIVE Organ allografts contain passenger leukocytes that are transferred to the recipient with the transplantation, but their functional relevance to the recipients immune system is still controversial. MATERIALS AND METHODS To clarify the functional capacity of passenger leukocytes, we attempted to enhance their effect in rat heart allograft recipients by selective depletion of recipient leukocytes using a monoclonal antibody (mAb) against a recipient-specific allotype of CD45 (RT7(a)). RESULTS Although antibody treatment of the recipient alone led to profound lymphopenia and reversible myelosuppression, additional transplantation of an major histocompatibility complex-incompatible heart graft from an RT7(b) donor led to lethal aplastic anemia in the recipients. This lethal effect was completely abrogated by postoperative anti-CD3 treatment of the recipient and was partially abrogated or delayed by depletion of passenger leukocytes through additional anti-RT7(b) antibody treatment of the recipient or gamma-irradiation of the graft. CONCLUSIONS The results suggest a role for both donor and recipient-type T cells for the induction of aplastic anemia in this model. The study shows that, under defined conditions, allogeneic passenger leukocytes in a heart graft can have a profound effect on the recipients immune system and bone marrow.

Effect of incomplete parathyroidectomy preserving entire parathyroid glands on renal graft function.

HYPOTHESIS Parathyroidectomy (PT) corrects tertiary hyperparathyroidism in patients who have received renal grafts but can result in deterioration of renal function. OBJECTIVE To compare different surgical procedures for their effect on renal function and efficacy to cure tertiary hyperparathyroidism. DESIGN A retrospective cohort study. SETTING University clinic. PATIENTS Eighty-three patients with functioning renal grafts receiving PT for the first time. INTERVENTIONS Group 1 received an incomplete PT, with at least 1 entire parathyroid gland (PG) remaining in situ (n = 12). Group 2 received an incomplete PT, with the most morphologically conserved PG partially resected (n = 22). Group 3 received a complete PT, with autotransplantation of PG tissue (n = 49). MAIN OUTCOMES MEASURES The primary end point was the postoperative change in glomerular filtration rate. Secondary end points were rates of redialysis, hypercalcemia, and hyperparathyroidism within 5 years. RESULTS A decrease in glomerular filtration rate occurred postoperatively in 75 patients (90%) and correlated significantly with the extent of PG resection. Recovery of renal function at month 6 was observed in group 1, but not in groups 2 and 3 (P < .001). Seven patients (8%) needed permanent dialysis (1 in group 2 and 6 in group 3). Hypercalcemia was abrogated in 78 patients (94%), without significant differences among the groups. Assessment of parathyroid hormone levels in accordance with target ranges from the Kidney Disease Outcomes Quality Initiative guidelines did not reveal significant differences in the rates of recurrent hyperparathyroidism. CONCLUSION Incomplete PT preserving at least 1 entire PG does not cause deterioration of renal graft function and provides long-term correction of hypercalcemia and tertiary hyperparathyroidism.