Distinct activation of primary human BDCA1(+) dendritic cells upon interaction with stressed or infected ß cells.

Derailment of immune responses can lead to autoimmune type 1 diabetes, and this can be accelerated or even induced by local stress caused by inflammation or infection. Dendritic cells (DCs) shape both innate and adaptive immune responses. Here, we report on the responses of naturally occurring human myeloid BDCA1(+) DCs towards differentially stressed pancreatic ß cells. Our data show that BDCA1(+) DCs in human pancreas-draining lymph node (pdLN) suspensions and blood-derived BDCA1(+) DCs both effectively engulf ß cells, thus mimicking physiological conditions. Upon uptake of enterovirus-infected, but not mock-infected cells, BDCA1(+) DCs induced interferon (IFN)-α/ß responses, co-stimulatory molecules and proinflammatory cytokines and chemokines. Notably, induction of stress in ß cells by ultraviolet irradiation, culture in serum-free medium or cytokine-induced stress did not provoke strong DC activation, despite efficient phagocytosis. DC activation correlated with the amount of virus used to infect ß cells and required RNA within virally infected cells. DCs encountering enterovirus-infected ß cells, but not those incubated with mock-infected or stressed ß cells, suppressed T helper type 2 (Th2) cytokines and variably induced IFN-γ in allogeneic mixed lymphocyte reaction (MLR). Thus, stressed ß cells have little effect on human BDCA1(+) DC activation and function, while enterovirus-infected ß cells impact these cells significantly, which could help to explain their role in development of autoimmune diabetes in individuals at risk.

Pig-to-monkey islet xenotransplantation using multi-transgenic pigs.

The generation of pigs with genetic modifications has significantly advanced the field of xenotransplantation. New genetically engineered pigs were produced on an α1,3-galactosyltransferase gene-knockout background with ubiquitous expression of human CD46, with islet beta cell-specific expression of human tissue factor pathway inhibitor and/or human CD39 and/or porcine CTLA4-lg. Isolated islets from pigs with 3, 4 or 5 genetic modifications were transplanted intraportally into streptozotocin-diabetic, immunosuppressed cynomolgus monkeys (n = 5). Immunosuppression was based on anti-CD154 mAb costimulation blockade. Monitoring included features of early islet destruction, glycemia, exogenous insulin requirement and histopathology of the islets at necropsy. Using these modified pig islets, there was evidence of reduced islet destruction in the first hours after transplantation, compared with two series of historical controls that received identical therapy but were transplanted with islets from pigs with either no or only one genetic modification. Despite encouraging effects on early islet loss, these multi-transgenic islet grafts did not demonstrate consistency in regard to long-term success, with only two of five demonstrating function beyond 5 months.

Fragility of epidermis and its consequence in dermatology.

The skin is the largest organ of the body, providing a protective barrier against bacteria, chemicals and physical insults while maintaining homeostasis in the internal environment. Such a barrier function the skin ensures protection against excessive water loss. The skin's immune defence consists of several facets, including immediate, non-specific mechanisms (innate immunity) and delayed, stimulus-specific responses (adaptive immunity), which contribute to fending off a wide range of potentially invasive microorganisms. This article is an overview of all known data about 'fragile skin'. Fragile skin is defined as skin with lower resistance to aggressions. Fragile skin can be classified into four categories up to its origin: physiological fragile skin (age, location), pathological fragile skin (acute and chronic), circumstantial fragile skin (due to environmental extrinsic factors or intrinsic factors such as stress) and iatrogenic fragile skin. This article includes the epidemiologic data, pathologic description of fragile skin with pathophysiological bases (mechanical and immunological role of skin barrier) and clinical description of fragile skin in atopic dermatitis, in acne, in rosacea, in psoriasis, in contact dermatitis and other dermatologic pathologies. This article includes also clinical cases and differential diagnosis of fragile skin (reactive skin) in face in adult population. In conclusion, fragile skin is very frequent worldwide and its prevalence varies between 25% and 52% in Caucasian, African and Asian population.

Investigation of lymphocyte depletion and repopulation using alemtuzumab (Campath-1H) in cynomolgus monkeys.

As the target CD52 molecule is expressed on erythrocytes of most nonhuman primate strains, using alemtuzumab in these species would cause massive hemolysis. Six cynomolgus monkeys of Indonesian origin, screened by agglutination assay for absence of CD52 on erythrocytes, were administered alemtuzumab in a cumulative dose to a maximum of 60 mg/kg. In two monkeys, mycophenolate mofetil (MMF) was added as maintenance therapy. Complete depletion of T and B lymphocytes (>99.5%) was achieved with 20 mg/kg alemtuzumab and was more profound than in monkeys treated with antithymocyte globulin (n = 5), as quantified by flow cytometry. Repopulation was suppressed by weekly injections of 10 mg/kg. Without MMF, repopulation of CD20(+)B cells and CD8(+)T cells was complete within 2 and 3 months, respectively, and repopulation of CD4(+)T cells was 67% after 1 year. MMF significantly delayed CD4(+)T-cell repopulation. Among repopulating CD4(+) and CD8(+) T cells, a phenotypic shift was observed from CD45RA(hi)CD62L(hi) naïve cells toward CD45RA(lo)CD62L(lo) effector memory cells. In lymph nodes, the depletion of naïve cells was more profound than of memory cells, which may have initiated a proliferation of memory cells. This model offers opportunities to investigate lymphocyte depletion/repopulation phenomena, as well as the efficacy of alemtuzumab in preclinical transplantation models.

Endoscopic gastric submucosal transplantation of islets (ENDO-STI): technique and initial results in diabetic pigs.

The results of transplantation of human donor islets into the portal vein (PV) in patients with diabetes are encouraging. However, there are complications, for example, hemorrhage, thrombosis and an immediate loss of islets through the 'instant blood-mediated inflammatory reaction' (IBMIR). The gastric submucosal space (GSMS) offers potential advantages. Islets were isolated from adult pigs. Recipient pigs were made diabetic by streptozotocin. Donor islets were injected into the GSMS through a laparotomy (Group 1A, n = 4) or endoscopically (Group 1B, n = 8) or into the PV through a laparotomy (Group 2, n = 3). The pigs were followed for a maximum of 28 days. Monitoring of C-peptide in Group 1 indicated that there was minimal immediate loss of islets whereas in Group 2 there was considerable loss from IBMIR. In Group 1, there were significant reductions in mean blood glucose and mean exogenous insulin requirement between pretransplantation and 20 days posttransplantation. In Group 2, there was no significant reduction in either parameter. Insulin-positive cells were seen in the GSMS in Group 1, but not in the liver in Group 2. Endoscopic gastric submucosal transplantation of islets (ENDO-STI) offers a minimally invasive and quick approach to islet transplantation, avoids IBMIR and warrants further exploration.

Long-term controlled normoglycemia in diabetic non-human primates after transplantation with hCD46 transgenic porcine islets.

Xenotransplantation of porcine islets into diabetic non-human primates is characterized by (i) an initial massive graft loss possibly due to the instant blood-mediated inflammatory reaction and (ii) the requirement of intensive, clinically unfriendly immunosuppressive therapy. We investigated whether the transgenic expression of a human complement-regulatory protein (hCD46) on porcine islets would improve the outcome of islet xenotransplantation in streptozotocin-induced diabetic Cynomolgus monkeys. Immunosuppression consisted of thymoglobulin, anti-CD154 mAb for costimulation blockade, and mycophenolate mofetil. Following the transplantation of islets from wild-type pigs (n = 2) or from 1,3-galactosyltransferase gene-knockout pigs (n = 2), islets survived for a maximum of only 46 days, as evidenced by return to hyperglycemia and the need for exogenous insulin therapy. The transplantation of islets from hCD46 pigs resulted in graft survival and insulin-independent normoglycemia in four of five monkeys for the 3 months follow-up of the experiment. One normalized recipient, selected at random, was followed for >12 months. Inhibition of complement activation by the expression of hCD46 on the pig islets did not substantially reduce the initial loss of islet mass, rather was effective in limiting antibody-mediated rejection. This resulted in a reduced need for immunosuppression to preserve a sufficient islet mass to maintain normoglycemia long-term.

The pig as the donor of pancreatic islets for men.

The promising results obtained using the "Edmonton protocol" for human islet transplantation has resulted in increased interest and growth of various clinical and basic science programs worldwide. Despite these encouraging results two major drawbacks remain: first, the immunosuppressive regimen necessary to prevent the rejection of this allotransplant dramatically affects the lifestyle of the treated patients precluding its implementation in younger diabetic individuals. Second, there continues to be an inadequate amount of islet tissue available to fulfill the needs of an increasing population of diabetic patients possibly interested in receiving this type of treatment. Besides the limited number of cadaveric organ donors, the current procedure used to isolate islets from their pancreata activates metabolic processes that promote the loss of beta cells in the islets. Thus, it becomes necessary to use more than one donor for a single recipient. To fulfill the continuously growing need for more transplantable islets, an immediately available, unlimited source of islets may be found in animals, which are able to produce a type of insulin that is very similar to the human one, and carry islets in quantities that may satisfy the metabolic requirements of diabetic patients: the pigs.

Pig-to-nonhuman primate islet xenotransplantation: a review of current problems.

Islet allotransplantation has been shown to have potential as a treatment for type 1 diabetic patients. Xenotransplantation, using the pig as a donor, offers the possibility of an unlimited number of islets. This comprehensive review focuses on experience obtained in pig-to-nonhuman primate models, particularly with regard to the different types of islets (fetal, neonatal, adult) and isolation procedures used, and the methods to determine islet viability. The advantages and disadvantages of the methods to induce diabetes (pancreatectomy, streptozotocin) are discussed. Experience in pig-to-nonhuman primate islet transplantation studies is reviewed, including discussion of the possible mechanisms of rejection and the immunosuppressive regimens used. The research carried out to date has led to workable animal models to study islet xenotransplantation, but several questions regarding methodology remain unanswered, and details of these practicalities require to be adequately addressed. The encouraging porcine islet survival reported recently provides an indicator for future immunosuppressive regimens.

A randomised, double blind, placebo controlled trial of the effect of theophylline in prevention of vasomotor nephropathy in very preterm neonates with respiratory distress syndrome.

BACKGROUND: Vasomotor nephropathy is a common renal dysfunction in very preterm neonates. OBJECTIVE: To determine whether theophylline could prevent vasomotor nephropathy in very preterm infants with respiratory distress syndrome. METHODS: A randomised, double blind, placebo controlled trial of 50 preterm infants of gestational age < or = 32 weeks needing assisted ventilation. Infants received an intravenous dose of theophylline (1 mg/kg) or placebo for three days. The 24 hour urine volume was measured daily. On days 2, 5, and 11, blood samples and 12 hour urine collections were analysed for electrolytes, creatinine, and urea. RESULTS: On day 1, urine output was significantly higher in the theophylline (2.4 (0.9) ml/kg/h) than the placebo (1.6 (1.0) ml/kg/h; p = 0.023) group (values are mean (SD)). The incidence of oligoanuria was significantly lower in the theophylline treated (5%) than the placebo (33%) group. Twenty four hours after the first administration of theophylline/placebo, serum creatinine concentration was significantly lower in the theophylline (0.76 (0.23) mg/dl) than the placebo (1.0 (0.41) mg/dl; p = 0.025) group. On day 5 an increase in serum creatinine was observed in both groups. On day 11 a significant reduction in serum creatinine was observed, compared with day 5, with no difference between the two groups. CONCLUSION: The results suggest that, in very preterm infants with respiratory distress syndrome, early theophylline administration improves renal function during the first two days of life.

Improved human islet isolation using a new enzyme blend, liberase.

Enzymatic digestion of donor pancreases is a vital step in human and large mammalian islet isolation. The variable enzymatic activities of different batches of commercially available collagenase is a major obstacle in achieving reproducibility in islet isolation procedures. In the present work, the effectiveness of Liberase, a standardized mixture of highly purified enzymes recently developed for the separation of human islets, was compared with that of a traditional collagenase preparation (type P). The results of 50 islet isolations using Liberase enzyme were compared with those of 36 isolations with collagenase, type P. No significant differences in donor age, cold ischemia time, digestion time, or weight of the pancreases were observed between the two groups. Islet yield was significantly higher in the group where the Liberase enzyme was used. All parameters examined (islet number, islet number per gram of tissue, islet equivalent number, and islet equivalent number per gram of tissue) were significantly improved when Liberase enzyme was used. Different lots of Liberase enzyme were tested, and no difference was observed. Islets isolated with Liberase enzyme were also of larger size and were much less fragmented, suggesting a gentler enzymatic action and better preservation of anatomical integrity. Islets isolated with Liberase enzyme, assessed both in vitro and in vivo, revealed a functional profile similar to that of islets separated with collagenase. Liberase enzyme appears, therefore, to represent a new powerful tool for improving the quality of human islet isolation.

Transplantation of allogeneic islets of Langerhans in the rat liver: effects of macrophage depletion on graft survival and microenvironment activation.

Early impairment of islet function and graft loss limit the success of allogeneic islet transplantation. Nonspecific inflammatory events occurring at the transplant site immediately after grafting, involving the production of cytokines and free radicals and sinusoidal endothelial cell (SEC) activation, may contribute to islet cell damage. To evaluate whether Kupffer cell inactivation would result in prolonged allograft survival in a model system of intrahepatic islet transplantation in rats, we systemically administered either gadolinium chloride (GdCl3) or dichloromethylene diphosphonate (Cl2MDP) to assess the effects of macrophage inactivation on rejection and on the release of proinflammatory molecules, as well as to assess the functional profile of SEC. The results obtained were compared with those observed in untreated, sham-injected animals and in rats receiving intraportal infusions of microbeads. Transient macrophage inhibition, particularly in hepatic Kupffer cells, is associated with significant prolongation of graft survival after intraportal islet allotransplantation (ITx) in rats: 7.2 days in the control group versus 11.9 days in the GdCl3 group (P < 0.01) and 15.6 days in the Cl2MDP group (P < 0.0006), respectively. Although systemic release of inflammatory mediators was observed only when islet transplantations were performed and it could be inhibited by macrophage-targeting treatments, perturbation of the functional profile of endothelial cells was also observed when microembolization was induced by the use of microbeads and could not be prevented by macrophage inhibition. These experiments provide evidence to support the concept that macrophages play a key role in early inflammatory events known to adversely affect islet engraftment and suggest that manipulation of nonspecific immune activation by inhibition of macrophage function may facilitate hepatic engraftment of islet allografts. The mechanisms mediating this effect are likely to include prevention of release of tumor necrosis factor-alpha, interleukin-1beta, and NO and interference with the rate of immune response to the islets.

Transplantation of islets of Langerhans in patients with insulin-requiring diabetes mellitus undergoing orthotopic liver transplantation--the Miami experience.

Most patients with cirrhosis of the liver have detectable insulin resistance. In 60-80% of patients with cirrhosis, impaired glucose tolerance can be uncovered; approximately 20% of these patients eventually develop overt diabetes. Theoretically, insulin resistance and glucose intolerance could be improved or reversed by orthotopic liver transplantation alone or in association with a simultaneous transplant of pancreatic islet cells from the same donor. To investigate these possibilities we initiated a pilot study of simultaneous liver and pancreatic islet cell transplantation in seven patients with diabetes and liver cirrhosis. Donor bone marrow cells were also infused to enhance the acceptance of the grafts. Seven patients who received only orthotopic liver transplantation and donor bone marrow cells were used as historical controls. The preliminary results of this pilot trial suggest that islet cell transplantation in conjunction with orthotopic liver transplantation improves glucose metabolism in patients with liver cirrhosis in association with reduced insulin requirements and HbA1c levels. These results were evident in spite of pre- and post-transplant basal C-peptide levels that were unchanged. Further evaluation of the effects of orthotopic liver transplantation with or without islet cell transplantation will require a randomized prospective trial including accurate metabolic evaluation with the euglycemic insulin clamp technique.

Human islet allografts in patients with type 2 diabetes undergoing liver transplantation.

BACKGROUND: Most patients with cirrhosis have insulin resistance and impaired glucose tolerance, and 20% eventually develop diabetes. Although diabetes in this setting may be reversible after orthotopic liver transplantation (OLTx), immunosuppressive agents administered after transplantation could exacerbate this disease. We report the results of the first pilot trial of islet cell transplantation (ICTx) in patients with diabetes undergoing OLTx. METHODS: Five patients with diabetes and liver cirrhosis underwent OLTx and ICTx. Donor bone marrow cells were also infused to enhance the acceptance of the graft. We identified seven patients who received only OLTx and donor bone marrow cells as historical controls. RESULTS: Preliminary results suggest that ICTx in conjunction with OLTx may improve glucose metabolism (insulin requirement, hemoglobin A1c) in patients with liver cirrhosis. However, there was virtually no change in pre- and posttransplant basal C-peptide levels in the recipients of OLTx + ICTx. CONCLUSIONS: We are planning to further evaluate the effect of OLTx with or without ICTx in a randomized prospective trial, using euglycemic insulin clamp studies.

Antenatal risk factors for germinal matrix hemorrhage and intraventricular hemorrhage in preterm infants.

OBJECTIVES: This study was designed to evaluate the effect of antenatal risk factors on the occurrence of germinal matrix hemorrhage or intraventricular hemorrhage in preterm infants. STUDY DESIGN: Antenatal factors were evaluated in 302 infants delivered between 24 and 33 completed weeks gestation. Ultrasonographic screening of intracranial hemorrhage was carried out in all the infants. The association between risk factors and neonatal intracranial hemorrhage was evaluated with both univariate and multivariate models. RESULTS: In stepwise logistic regression analysis, birthweight was a better predictor of neonatal germinal matrix hemorrhage than gestational age. Conversely, gestational age better predicted intraventricular hemorrhage than did birthweight. Risk factors for neonatal germinal matrix hemorrhage and intraventricular hemorrhage were dissimilar. A history of heavy (> 10 cigarettes/day) maternal smoking on admission increased the risk of germinal matrix hemorrhage three-fold (odds ratio = 3.35; 95% C.I. 1.24-9.07). Antenatal corticosteroid use reduced the risk of intraventricular hemorrhage by 76% (odds ratio = 0.24; 95% C.I. 0.09-0.61). Among patients with spontaneous preterm delivery or premature rupture of fetal membranes, the presence of labor was a significant effect modifier of the gestational-age associated risk of germinal matrix hemorrhage-intraventricular hemorrhage. CONCLUSIONS: Risk factors for neonatal germinal matrix hemorrhage are different from those for intraventricular hemorrhage. Most antenatal factors, especially those affecting fetal maturity, could influence the progression rather than the onset of intracranial hemorrhage.

[Kidney transplantation in the HBsAg+ patient. Our experience]. / Il trapianto renale in pazienti HBsAg+. Nostra esperienza.

HbsAg serum positivity in patients on the waiting list for kidney transplant and modifications of survival rate and transplanted kidney function deriving from this clinical situation are nowadays a matter of investigation and scientifical controversy. Authors analyse data deriving from their own series of renal transplant in HbsAg+ patients comparing them with literature.

Nursing role in advance proxy planning for Alzheimer patients.

Patients with Alzheimer's disease or other types of dementia become unable to make decisions regarding their care. Advance proxy planning provides a mechanism for protecting these patients' self-determination.

Improved quality of life following total pancreatectomy and auto-islet transplantation for chronic pancreatitis.

BACKGROUND: Total pancreatectomy (TP) with auto-islet transplant (AIT) is an extreme treatment for chronic pancreatitis, and we reviewed our experience to assess the impact on quality of life (QOL). METHODS: A prospective cohort study from 2007 through 2010 with pre- and postoperative assessments of the Depression Anxiety Stress Scale, Pain Disability Index, and visual analogue pain scale was performed. RESULTS: Twenty patients underwent TP-AIT with a median follow-up of 12 months (6.75-24 months). All patients reported moderate (45 %) to severe (55 %) pain prior to surgery. TP-AIT resulted in significant decreases in abdominal pain (p < 0.001), 80 % reporting no or mild pain. Despite pain improvement, only 30 % discontinued narcotics. Improvements in all PDI QOL domains improved from 79 to 90 % (p = 0.002), with greatest improvements seen in those without prior pancreatic surgery, younger patients, and in those with higher levels of preoperative pain. Patients were less affected by depression and anxiety prior to surgery, but 60 and 70 % did show improvement in depression and anxiety, respectively (p = 0.033). Sixteen patients (80 %) required exogenous insulin at last follow-up (mean total dose of insulin 11.6 U/day). CONCLUSIONS: TP-AIT significantly improves pain and QOL measures in appropriately selected patients with CP.