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1.  Erratum: Body mass index and outcome in renal transplant recipients: a systematic review and meta-analysis 
BMC Medicine  2015;13:141.
This is an Erratum to BMC Medicine 2015, 13:111 indicating the correct name for one of the authors.
Please see related article:
PMCID: PMC4469463  PMID: 26076728
2.  GITR engagement in combination with CTLA-4 blockade completely abrogates immunosuppression mediated by human liver tumor-derived regulatory T cells ex vivo 
Oncoimmunology  2015;4(12):e1051297.
In liver cancer tumor-infiltrating regulatory T cells (Ti-Treg) are potent suppressors of tumor-specific T-cell responses and express high levels of the Treg-associated molecules cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) and glucocorticoid-induced tumor necrosis factor receptor (GITR). In this study, we have evaluated the capacity of GITR-ligation, CTLA-4-blockade and a combination of both treatments to alleviate immunosuppression mediated by Ti-Treg. Using ex vivo isolated cells from individuals with hepatocellular carcinoma (HCC) or liver metastases from colorectal cancer (LM-CRC) we show that treatment with a soluble form of the natural ligand of GITR (GITRL), or with blocking antibodies to CTLA-4, reduces the suppression mediated by human liver tumor-infiltrating CD4+Foxp3+ Treg, thereby restoring proliferation and cytokine production by effector T cells. Importantly, combined treatment with low doses of both molecules exhibited stronger recovery of T cell function compared with either treatment alone. Our data suggest that in patients with primary and secondary liver cancer both GITR-ligation and anti-CTLA-4 mAb can improve the antitumor immunity by abrogating Ti-Treg mediated suppression.
PMCID: PMC4635937  PMID: 26587321
cytotoxic T lymphocyte-associated antigen 4 (CTLA-4); glucocorticoid-induced tumor necrosis factor receptor (GITR); hepatocellular carcinoma (HCC); liver metastases from colorectal cancer (LM-CRC); regulatory T cells (Treg)
3.  Fasting protects against the side effects of irinotecan but preserves its anti-tumor effect in Apc15lox mutant mice 
Cell Cycle  2015;14(14):2333-2339.
Irinotecan is a widely used topoisomerase-I-inhibitor with a very narrow therapeutic window because of its severe toxicity. In the current study we have examined the effects of fasting prior to irinotecan treatment on toxicity and anti-tumor activity. FabplCre;Apc15lox/+ mice, which spontaneously develop intestinal tumors, of 27 weeks of age were randomized into 3-day fasted and ad libitum fed groups, followed by treatment with a flat-fixed high dose of irinotecan or vehicle. Side-effects were recorded until 11 days after the start of the experiment. Tumor size, and markers for cell-cycle activity, proliferation, angiogenesis, and senescence were measured. Fasted mice were protected against the side-effects of irinotecan treatment. Ad libitum fed mice developed visible signs of discomfort including weight loss, lower activity, ruffled coat, hunched-back posture, diarrhea, and leukopenia. Irinotecan reduced tumor size in fasted and ad libitum fed groups similarly compared to untreated controls (2.4 ± 0.67 mm and 2.4 ± 0.82 mm versus 3.0 ± 1.05 mm and 2.8 ± 1.08 mm respectively, P < 0.001). Immunohistochemical analysis showed reduced proliferation, a reduced number of vascular endothelial cells, and increased levels of senescence in tumors of both irinotecan treated groups. In conclusion, 3 days of fasting protects against the toxic side-effects of irinotecan in a clinically relevant mouse model of spontaneously developing colorectal cancer without affecting its anti-tumor activity. These results support fasting as a powerful way to improve treatment of colorectal carcinoma patients.
PMCID: PMC4613178  PMID: 25955194
APC; colorectal cancer; fasting; irinotecan; mouse models
4.  Tumor-infiltrating plasmacytoid dendritic cells promote immunosuppression by Tr1 cells in human liver tumors 
Oncoimmunology  2015;4(6):e1008355.
CD4+ type 1 T regulatory (Tr1) cells have a crucial role in inducing tolerance. Immune regulation by these cells is mainly mediated through the secretion of high amounts of IL-10. Several studies have suggested that this regulatory population may be involved in tumor-mediated immune-suppression. However, direct evidence of a role for Tr1 cells in human solid tumors is lacking. Using ex vivo isolated cells from individuals with hepatocellular carcinoma (HCC; n = 39) or liver metastases from colorectal cancer (LM-CRC; n = 60) we identify a CD4+FoxP3−IL-13−IL-10+ T cell population in tumors of individuals with primary or secondary liver cancer that is characterized as Tr1 cells by the expression of CD49b and the lymphocyte activation gene 3 (LAG-3) and strong suppression activity of T cell responses in an IL-10 dependent manner. Importantly, the presence of tumor-infiltrating Tr1 cells is correlated with tumor infiltration of plasmacytoid dendritic cells (pDCs). pDCs exposed to tumor-derived factors enhance IL-10 production by Tr1 cells through up-regulation of the inducible co-stimulatory ligand (ICOS-L). These findings suggest a role for pDCs and ICOS-L in promoting intra-tumoral immunosuppression by Tr1 cells in human liver cancer, which may foster tumor progression and which might interfere with attempts of immunotherapeutic intervention.
PMCID: PMC4485712  PMID: 26155417
colorectal cancer liver metastasis; hepatocellular carcinoma; ICOS-L; IL-10; Immunotherapy; Tr1 cells; CFSE, carboxyfluorescein diacetate succinimidyl ester; CMV, cytomegalovirus; HCC, hepatocellular carcinoma; LM-CRC, liver metastasis from colorectal cancer; pDCs, plasmacytoid dendritic cells; TFL, tumor-free area of the liver; TILs, tumor-infiltrating lymphocytes; Tr1, CD4+ type 1 T regulatory
5.  Hydroxylated collagen peptide in urine as biomarker for detecting colorectal liver metastases 
The clinical efficacy of carcinoembryonic antigen (CEA) as a marker of colorectal liver metastasis is limited, motivating a search for new biomarkers. Recently, urine proteomic analysis revealed AGPP(-OH)GEAGKP(-OH)GEQGVP(-OH)GDLGAP(-OH)GP (AGP), a promising peptide for this application. This study aimed to determine whether combining urine AGP testing with serum CEA analyses improves the sensitivity of detecting colorectal liver metastases. Urine samples from 100 patients with CRLM were collected prospectively and compared to three control groups: healthy kidney donors, patients who were relapse-free for 24 months after curative CRLM surgery, and primary colorectal cancer patients. A stable isotope labeled peptide standard was used to quantify the abundance of AGP in urine samples by selective reaction monitoring. Combined testing of urine AGP levels and serum CEA levels revealed a significantly increased sensitivity compared to CEA alone (85% vs. 68%, P<0.001; specificity 84% and 91%, respectively). No correlation was found between CEA and AGP-positive test results within individual patients (r2 = 0.08). Urine AGP testing was negative in the three control groups. These results indicate that collagen-derived urine AGP peptide with a specific hydroxylation pattern combined with serum CEA levels may significantly improve the detection of colorectal liver metastases in patients at risk.
PMCID: PMC4859663  PMID: 27186406
Colorectal liver metastases; urine; collagen; biomarker; mass spectrometry
6.  Human Allogeneic Bone Marrow and Adipose Tissue Derived Mesenchymal Stromal Cells Induce CD8+ Cytotoxic T Cell Reactivity 
For clinical applications, Mesenchymal Stromal Cells (MSC) can be isolated from bone marrow and adipose tissue of autologous or allogeneic origin. Allogeneic cell usage has advantages but may harbor the risk of sensitization against foreign HLA. Therefore, we evaluated whether bone marrow and adipose tissue-derived MSC are capable of inducing HLA-specific alloreactivity.
MSC were isolated from healthy human Bone Marrow (BM-MSC) and adipose tissue (ASC) donors. Peripheral Blood Mononuclear Cells (PBMC) were co-cultured with HLA-AB mismatched BM-MSC or ASC precultured with or without IFNy. After isolation via FACS sorting, the educated CD8+ T effector populations were exposed for 4 hours to Europium labeled MSC of the same HLA make up as in the co-cultures or with different HLA. Lysis of MSC was determined by spectrophotometric measurement of Europium release.
CD8+ T cells educated with BM-MSC were capable of HLA specific lysis of BM-MSC. The maximum lysis was 24% in an effector:target (E:T) ratio of 40:1. Exposure to IFNγ increased HLA-I expression on BM-MSC and increased lysis to 48%. Co-culturing of PBMC with IFNγ-stimulated BM-MSC further increased lysis to 76%. Surprisingly, lysis induced by ASC was significantly lower. CD8+ T cells educated with ASC induced a maximum lysis of 13% and CD8+ T cells educated with IFNγ-stimulated ASC of only 31%.
Allogeneic BM-MSC, and to a lesser extend ASC, are capable of inducing HLA specific reactivity. These results should be taken into consideration when using allogeneic MSC for clinical therapy.
PMCID: PMC3982127  PMID: 24729944
Mesenchymal stromal cells; Bone marrow; Adipose tissue; Alloreactivity; HLA class I; CD8+ cytotoxicity
7.  Human Bone Marrow- and Adipose Tissue-derived Mesenchymal Stromal Cells are Immunosuppressive In vitro and in a Humanized Allograft Rejection Model 
Recent studies with bone marrow (BM)-derived Mesenchymal Stromal Cells (MSC) in transplant recipients demonstrate that treatment with MSC is safe and clinically feasible. While BM is currently the preferred source of MSC, adipose tissue is emerging as an alternative. To develop efficient therapies, there is a need for preclinical efficacy studies in transplantation. We used a unique humanized transplantation model to study the in vivo immunosuppressive effect of human BM-MSC and adipose tissue-derived MSC (ASC).
Gene expression of BM-MSC and ASC and their capacity to inhibit activated PBMC proliferation was evaluated. The in vivo immunosuppressive effect of BM-MSC and ASC was studied in a humanized mouse model. SCID mice were transplanted with human skin grafts and injected with human allogeneic PBMC with or without administration of BM-MSC or ASC. The effect of MSC on skin graft rejection was studied by immunohistochemistry and PCR.
BM-MSC and ASC expressed TGFβ, CXCL-10 and IDO. IDO expression and acitivity increased significantly in BM-MSC and ASC upon IFN-γ stimulation. IFN-γ stimulated BM-MSC and ASC inhibited the proliferation of activated PBMC in a significant and dose dependent manner. In our humanized mouse model, alloreactivity was marked by pronounced CD45+ T-cell infiltrates consisting of CD4+ and CD8+ T cells and increased IFN-γ expression in the skin grafts which were all significantly inhibited by both BM-MSC and ASC.
BM-MSC and ASC are immunosuppressive in vitro and suppress alloreactivity in a preclinical humanized transplantation model.
PMCID: PMC3963708  PMID: 24672744
Adipose tissue; Allograft rejection; Bone marrow; Immunomodulation; Mesenchymal stromal cells
8.  Management strategy after diagnosis of Abernethy malformation: a case report 
The Abernethy malformation is a rare anomaly with a widely variable clinical presentation. Many diagnostic dilemmas have been reported. Nowadays, with the evolution of medical imaging, diagnosis can be made more easily, but management of patients with an Abernethy malformation is still open for discussion.
Case presentation
In this case study, we describe a 34-year-old Caucasian man who presented with a large hepatocellular carcinoma in the presence of an Abernethy malformation, which was complicated by the development of pulmonary arterial hypertension.
This case underlines the importance of regular examination of patients with an Abernethy malformation, even in older patients, to prevent complications and to detect liver lesions at an early stage.
PMCID: PMC3419678  PMID: 22742057
hepatocellular carcinoma; arteriovenous malformation; Abernethy malformation; pulmonary hypertension
10.  Laparoscopic versus open peritoneal dialysis catheter insertion, the LOCI-trial: a study protocol 
BMC Surgery  2011;11:35.
Peritoneal dialysis (PD) is an effective treatment for end-stage renal disease. It allows patients more freedom to perform daily activities compared to haemodialysis. Key to successful PD is the presence of a well-functioning dialysis catheter. Several complications, such as in- and outflow obstruction, peritonitis, exit-site infections, leakage and migration, can lead to catheter removal and loss of peritoneal access. Currently, different surgical techniques are in practice for PD-catheter placement. The type of insertion technique used may greatly influence the occurrence of complications. In the literature, up to 35% catheter failure has been described when using the open technique and only 13% for the laparoscopic technique. However, a well-designed randomized controlled trial is lacking.
The LOCI-trial is a multi-center randomized controlled, single-blind trial (pilot). The study compares the laparoscopic with the open technique for PD catheter insertion. The primary objective is to determine the optimum placement technique in order to minimize the incidence of catheter malfunction at 6 weeks postoperatively. Secondary objectives are to determine the best approach to optimize catheter function and to study the quality of life at 6 months postoperatively comparing the two operative techniques.
This study will generate evidence on any benefits of laparoscopic versus open PD catheter insertion.
Trial registration
Dutch Trial Register NTR2878
PMCID: PMC3266194  PMID: 22185091
11.  Remarkable changes in the choice of timing to discuss organ donation with the relatives of a patient: a study in 228 organ donations in 20 years 
Critical Care  2011;15(5):R235.
We studied whether the choice of timing of discussing organ donation for the first time with the relatives of a patient with catastrophic brain injury in The Netherlands has changed over time and explored its possible consequences. Second, we investigated how thorough the process of brain death determination was over time by studying the number of medical specialists involved. And we studied the possible influence of the Donor Register on the consent rate.
We performed a retrospective chart review of all effectuated brain dead organ donors between 1987 and 2009 in one Dutch university hospital with a large neurosurgical serving area.
A total of 271 medical charts were collected, of which 228 brain dead patients were included. In the first period, organ donation was discussed for the first time after brain death determination (87%). In 13% of the cases, the issue of organ donation was raised before the first EEG. After 1998, we observed a shift in this practice. Discussing organ donation for the first time after brain death determination occurred in only 18% of the cases. In 58% of the cases, the issue of organ donation was discussed before the first EEG but after confirming the absence of all brain stem reflexes, and in 24% of the cases, the issue of organ donation was discussed after the prognosis was deemed catastrophic but before a neurologist or neurosurgeon assessed and determined the absence of all brain stem reflexes as required by the Dutch brain death determination protocol.
The phases in the process of brain death determination and the time at which organ donation is first discussed with relatives have changed over time. Possible causes of this change are the introduction of the Donor Register, the reintroduction of donation after circulatory death and other logistical factors. It is unclear whether the observed shift contributed to the high refusal rate in The Netherlands and the increase in family refusal in our hospital in the second studied period. Taking published literature on this subject into account, it is possible that this may have a counterproductive effect.
PMCID: PMC3334786  PMID: 21982557
12.  Hand-assisted retroperitoneoscopic versus standard laparoscopic donor nephrectomy: HARP-trial 
BMC Surgery  2010;10:11.
Transplantation is the only treatment offering long-term benefit to patients with chronic kidney failure. Live donor nephrectomy is performed on healthy individuals who do not receive direct therapeutic benefit of the procedure themselves. In order to guarantee the donor's safety, it is important to optimise the surgical approach. Recently we demonstrated the benefit of laparoscopic nephrectomy experienced by the donor. However, this method is characterised by higher in hospital costs, longer operating times and it requires a well-trained surgeon. The hand-assisted retroperitoneoscopic technique may be an alternative to a complete laparoscopic, transperitoneal approach. The peritoneum remains intact and the risk of visceral injuries is reduced. Hand-assistance results in a faster procedure and a significantly reduced operating time. The feasibility of this method has been demonstrated recently, but as to date there are no data available advocating the use of one technique above the other.
The HARP-trial is a multi-centre randomised controlled, single-blind trial. The study compares the hand-assisted retroperitoneoscopic approach with standard laparoscopic donor nephrectomy. The objective is to determine the best approach for live donor nephrectomy to optimise donor's safety and comfort while reducing donation related costs.
This study will contribute to the evidence on any benefits of hand-assisted retroperitoneoscopic versus standard laparoscopic donor nephrectomy.
Trial Registration
Dutch Trial Register NTR1433
PMCID: PMC2856541  PMID: 20338030

Results 1-12 (12)