Autologous Islet Transplantation in Patients Requiring Pancreatectomy: A Broader Spectrum of Indications Beyond Chronic Pancreatitis.

Islet autotransplantation (IAT) is usually performed in patients undergoing pancreatic surgery for chronic pancreatitis. In the present series, IAT was offered also to patients undergoing pancreatic surgery for both nonmalignant and malignant diseases, having either completion pancreatectomy as treatment for severe pancreatic fistulas (n = 21) or extensive distal pancreatectomy for neoplasms of the pancreatic neck (n = 19) or pancreatoduodenectomy because of the high risk of pancreatic fistula (n = 32). Fifty-eight of 72 patients who were eligible to this broader spectrum of indication actually received IAT. There was no evidence of a higher-than-expected rate of major complications for pancreatectomy. Forty-five patients receiving IAT were still alive at the time of the last scheduled follow-up (1375 ± 365 days). Eighteen (95%) of 19 and 11 (28%) of 39 patients reached insulin independence after partial or total pancreatectomy, respectively. The metabolic results were dependent on the transplanted islet mass. Thirty-one of 58 patients had malignant diseases of the pancreas or periampullary region, and only three patients developed ex novo liver metastases after IAT (median follow-up 914 ± 382 days). Our data demonstrate the feasibility, efficacy, and safety of IAT for a broader spectrum of clinical indications beyond chronic pancreatitis.

No evidence of enteroviruses in the intestine of patients with type 1 diabetes.

AIMS/HYPOTHESIS: The purpose of this study was to investigate whether the gut mucosa is a reservoir for enterovirus persistence in patients with type 1 diabetes. METHODS: Small intestine biopsy samples from 25 individuals at different stages of type 1 diabetes, 21 control individuals and 27 individuals with coeliac disease were analysed for the presence of enterovirus RNA by using both radioactive in-situ hybridisation and real-time RT-PCR and for the presence of enterovirus proteins by immunostaining with antibodies against VP1 and VP4-2-3 capsid proteins and virus polymerase. Lymphocytic enteropathy and serum anti-VP1 antibodies were also evaluated at the time of biopsy. Moreover, high-throughput sequencing was performed to identify viral transcripts or genomes. RESULTS: Enterovirus was not detected by in-situ hybridisation or RT-PCR in any of the individuals tested. Immunohistology revealed a few stained cells in the intestinal epithelium in a low number of individuals, with no difference between diabetic and non-diabetic individuals. Levels of serum IgG against VP1 did not differ between control individuals and those with diabetes or coeliac disease and no evidence of diabetes-related lymphocytic enteropathy was detected. High-throughput sequencing did not reveal specific enterovirus sequences in the gut mucosa of individuals with type 1 diabetes. CONCLUSIONS/INTERPRETATION: Prolonged/persistent enterovirus infections in gut mucosa are not common in patients with type 1 diabetes.

Ghrelin-producing epsilon cells in the developing and adult human pancreas.

AIMS/HYPOTHESIS: While the mechanisms of specification and the reciprocal relationships of the four types of endocrine cell (alpha, beta, delta and pancreatic polypeptide cells) within the human endocrine pancreas are well described in adults and during fetal development, ghrelin-immunoreactive cells (epsilon cells) remain poorly understood. METHODS: We studied epsilon cells in 24 human fetal pancreases between 11 and 39 weeks of development and in 32 pancreases from adult organ donors. RESULTS: We observed single epsilon cells scattered in primitive exocrine tissue from gestational week 13 in developing pancreas. Later in the developmental process, epsilon cells started to aggregate into clusters. From gestational week 21, epsilon cells were observed located around developing islets, forming an almost continuous layer at the peripheral rim of the islets. They remain localised on the mantle of the islets, although at different amounts, in the adult pancreas. Co-production of ghrelin with insulin, glucagon or somatostatin was not detected during fetal development. Co-production with pancreatic polypeptide was evident sporadically. Epsilon cells co-produced NK2 homeobox 2 and ISL LIM homeobox 1, but not NK6 homeobox 1 and paired box 6. A quantitative analysis was performed in the adult pancreas: there was an average of 1.17 + 1.17 epsilon cells per islet, the relative epsilon cell volume was 0.14 + 0.16% and the epsilon cell mass was 0.13 + 0.15 g. Neither sex nor age affected the epsilon cell mass, although there was a significant inverse correlation with BMI. CONCLUSIONS/INTERPRETATION: During fetal development epsilon cells show an ontogenetic and morphogenetic pattern that is distinct from that of alpha and beta cells.

High levels of donor CCL2/MCP-1 predict graft-related complications and poor graft survival after kidney-pancreas transplantation.

In this study we analyzed the role of CCL2, a member of the chemokine family, in early graft damage. Using simultaneous kidney-pancreas transplantation (SPK) as a model, we showed that brain death significantly increases circulating CCL2 levels in humans. We found that in such situations, high donor CCL2 levels (measured before organ recovery and at the onset of cold preservation) correlate with increased postreperfusion release of CCL2 by both the graft and recipient throughout the week following transplantation (n = 28). In a retrospective study of 77 SPK recipients, we found a significant negative association between high donor levels of CCL2 and graft survival. Decreased survival in these patients is related to early posttransplant complications, including a higher incidence of pancreas thrombosis and delayed kidney function. Taken together our data indicate that high CCL2 levels in the donor serum predict both an increase in graft/recipient CCL2 production and poor graft survival. This suggests that the severity of the inflammatory response induced by brain death influences the posttransplant inflammatory response, independent of subsequent ischemia and reperfusion.

Intrahepatic islet transplant in the mouse: functional and morphological characterization.

Although in a clinical setting islet transplantation is normally performed by percutaneous intrahepatic infusion, the kidney capsule has been the site of choice in nearly all the studies using mice. In the present study, we extensively characterized the mouse model of intraportally transplanted islets with the purpose to propose it as a model to study islet transplantation. C57BL/6 (n = 78) and BALB/C (n = 53) recipients were transplanted with 400 autologous islets alternatively through the portal vein (PV-Tx) or under the kidney capsule (KC-Tx). Glucose concentration during the first hour after syngeneic islet infusion was associated with subsequent long-term function confirming that early events have long-term effects on graft function. In both strains tested the probability to achieve islet function was significantly lower for PV-Tx than KC-Tx. Also in allogeneic models (C57BL/6 to BALB/C, n = 104; BALB/C to C57BL/6, n = 77) the probability to achieve primary function was significantly lower for PV-Tx than KC-Tx and the site of transplantation significantly affected the graft survival. Histological evaluation of livers showed the presence of features (embolism, thrombosis, focal areas of liver necrosis) that are absent in the kidney subcapsular site. Finally, significant differences in the outcome of PV-Tx were observed between the Th type 1 inflammatory-prone C57BL/6 mouse and the type 2 inflammatory-prone BALB/C mouse. Intraportal islet graft model has some features that are more similar to human clinical islet transplantation and should be used as a model to study not only engraftment but also mechanisms of immune suppression and immune tolerance.

A preclinical evaluation of pemetrexed and irinotecan combination as second-line chemotherapy in pancreatic cancer.

Gemcitabine (GEM)-based chemotherapy is regarded as the standard treatment of pancreatic adenocarcinoma, but yields a very limited disease control. Very few studies have investigated salvage chemotherapy after failure of GEM or GEM-containing chemotherapy and preclinical studies attempting to widen the therapeutic armamentarium, not including GEM, are warranted. MIA PaCa2, CFPAC-1 and Capan-1 pancreatic cancer cell lines were treated with GEM, fluouracil (5-FU), docetaxel (DCT), oxaliplatin (OXP), irinotecan (CPT-11), pemetrexed (PMX) and raltitrexed (RTX) as single agent. Pemetrexed, inducing apoptosis with IC50s under the Cmax in the three lines tested, appeared the most effective drug as single agent. Based on these results, schedule- and concentration-dependent drug interactions (assessed using the combination index) of PMX/GEM, PMX/DCT and PMX-CPT-11 were evaluated. The combinatory study clearly indicated the PMX and CPT-11 combination as the most active against pancreatic cancer. To confirm the efficacy of PMX-CPT-11 combination, we extended the study to a panel of 10 pancreatic cancer cell lines using clinically relevant concentrations (PMX 10 microM; CPT-11 1 microm). In eight of 10 lines, the PMX-CPT-11 treatment significantly reduced cell recovery and increased both the subG1 and caspase 3/7 fraction. After a 5-day wash out period, an increased fraction of subG1 and caspase3/7 persisted in PMX-CPT-11-pretreated cell lines and a significant reduction in the clonogenicity capacity was evident. Finally, in vivo, the PMX/CPT-11 combination showed the ability to inhibit xenograft tumours growth as second-line therapy after GEM treatment. The PMX and CPT-11 combination displays a strong schedule-independent synergistic cytotoxic activity against pancreatic cancer, providing experimental basis for its clinical testing as salvage chemotherapy in pancreatic cancer patients.

Rapamycin induces a caspase-independent cell death in human monocytes.

The immunosuppressive activity of rapamycin (RAPA) and its efficacy as an anti-rejection agent in organ transplantation have been ascribed principally to its anti-proliferative effects on T cells, while the activity on monocytes is partially unknown. In vitro, RAPA reduced monocyte survival by inducing a caspase-independent cell death. RAPA-induced monocyte cell death (RAPA-CD) was impeded by activation of granulocyte macrophage-colony stimulating factor family receptors or toll-like receptor 4, and by exposure to inflammatory cytokines. In vivo, in patients who received RAPA monotherapy as part of pre-conditioning for islet transplantation, RAPA affected survival of myeloid lineage cells. In the peripheral blood, CD33(+) and CD14(+) cells decreased, whereas lymphocytes appeared unaffected. In the bone marrow, myeloid precursors such as CD15(+) and CD15(+)/CD16(+) were selectively and significantly decreased, but no major cytotoxic effects were observed. The RAPA-CD suggests a dependence of monocytes on mammalian target of RAPA pathways for nutrient usage, and this feature implies that RAPA could be selectively useful as a treatment to reduce monocytes or myeloid cells in conditions where these cells negatively affect patient, suggesting a potential anti-inflammatory action of this drug.