OBJECTIVEThe safety of dendritic cells to selectively suppress autoimmunity, especially in type 1 diabetes, has never been ascertained. We investigated the safety of autologous dendritic cells, stabilized into an immunosuppressive state, in established adult type 1 diabetic patients.RESEARCH DESIGN AND METHODSA randomized, double-blind, phase I study was conducted. A total of 10, otherwise generally healthy, insulin-requiring type 1 diabetic patients between 18 and 60 years of age, without any other known or suspected health conditions, received autologous dendritic cells, unmanipulated or engineered ex vivo toward an immunosuppressive state. Ten million cells were administered intradermally in the abdomen once every 2 weeks for a total of four administrations. The primary end point determined the proportion of patients with adverse events on the basis of the physician’s global assessment, hematology, biochemistry, and immune monitoring for a period of 12 months.RESULTSThe dendritic cells were safely tolerated. There were no discernible adverse events in any patient throughout the study. Other than a significant increase in the frequency of peripheral B220+ CD11c− B cells, mainly seen in the recipients of engineered dendritic cells during the dendritic cell administration period, there were no statistically relevant differences in other immune populations or biochemical, hematological, and immune biomarkers compared with baseline.CONCLUSIONSTreatment with autologous dendritic cells, in a native state or directed ex vivo toward a tolerogenic immunosuppressive state, is safe and well tolerated. Dendritic cells upregulated the frequency of a potentially beneficial B220+ CD11c− B-cell population, at least in type 1 diabetes autoimmunity.
OBJECTIVEExcessive endogenous glucose production contributes to fasting hyperglycemia in diabetes. This effect stems from inept insulin suppression of hepatic gluconeogenesis. To understand the underlying mechanisms, we studied the ability of forkhead box O6 (FoxO6) to mediate insulin action on hepatic gluconeogenesis and its contribution to glucose metabolism.RESEARCH DESIGN AND METHODSWe characterized FoxO6 in glucose metabolism in cultured hepatocytes and in rodent models of dietary obesity, insulin resistance, or insulin-deficient diabetes. We determined the effect of FoxO6 on hepatic gluconeogenesis in genetically modified mice with FoxO6 gain- versus loss-of-function and in diabetic db/db mice with selective FoxO6 ablation in the liver.RESULTSFoxO6 integrates insulin signaling to hepatic gluconeogenesis. In mice, elevated FoxO6 activity in the liver augments gluconeogenesis, raising fasting blood glucose levels, and hepatic FoxO6 depletion suppresses gluconeogenesis, resulting in fasting hypoglycemia. FoxO6 stimulates gluconeogenesis, which is counteracted by insulin. Insulin inhibits FoxO6 activity via a distinct mechanism by inducing its phosphorylation and disabling its transcriptional activity, without altering its subcellular distribution in hepatocytes. FoxO6 becomes deregulated in the insulin-resistant liver, accounting for its unbridled activity in promoting gluconeogenesis and correlating with the pathogenesis of fasting hyperglycemia in diabetes. These metabolic abnormalities, along with fasting hyperglycemia, are reversible by selective inhibition of hepatic FoxO6 activity in diabetic mice.CONCLUSIONSOur data uncover a FoxO6-dependent pathway by which the liver orchestrates insulin regulation of gluconeogenesis, providing the proof-of-concept that selective FoxO6 inhibition is beneficial for curbing excessive hepatic glucose production and improving glycemic control in diabetes.
Phase equilibrium relations in the liquidus temperature region of the system CaO-iron oxide-S O 2 in air were determined, using the quenching technique. The results are illustrated by means of a projection of the liquidus surface onto the composition triangle Ca0-Fe203-Si02. A supplementary diagram is presented in order to indicate true compositions of liquids at liquidus temperatures. Data obtained in the present investigation are combined with literature data to construct diagrams showing stability relations among crystalline phases at subsolidus temperatures. A diagram is also presented to show phase relations along the join CaO .Si02-2Ca0 .Fe20s.
OBJECTIVE—This study was aimed at ascertaining the efficacy of antisense oligonucleotide-formulated microspheres to prevent type 1 diabetes and to reverse new-onset disease. RESEARCH DESIGN AND METHODS—Microspheres carrying antisense oligonucleotides to CD40, CD80, and CD86 were delivered into NOD mice. Glycemia was monitored to determine disease prevention and reversal. In recipients that remained and/or became diabetes free, spleen and lymph node T-cells were enriched to determine the prevalence of Foxp3+ putative regulatory T-cells (Treg cells). Splenocytes from diabetes-free microsphere-treated recipients were adoptively cotransferred with splenocytes from diabetic NOD mice into NOD-scid recipients. Live-animal in vivo imaging measured the microsphere accumulation pattern. To rule out nonspecific systemic immunosuppression, splenocytes from successfully treated recipients were pulsed with β-cell antigen or ovalbumin or cocultured with allogeneic splenocytes. RESULTS—The microspheres prevented type 1 diabetes and, most importantly, exhibited a capacity to reverse clinical hyperglycemia, suggesting reversal of new-onset disease. The microspheres augmented Foxp3+ Treg cells and induced hyporesponsiveness to NOD-derived pancreatic β-cell antigen, without compromising global immune responses to alloantigens and nominal antigens. T-cells from successfully treated mice suppressed adoptive transfer of disease by diabetogenic splenocytes into secondary immunodeficient recipients. Finally, microspheres accumulated within the pancreas and the spleen after either intraperitoneal or subcutaneous injection. Dendritic cells from spleen of the microsphere-treated mice exhibit decreased cell surface CD40, CD80, and CD86. CONCLUSIONS—This novel microsphere formulation represents the first diabetes-suppressive and reversing nucleic acid vaccine that confers an immunoregulatory phenotype to endogenous dendritic cells.
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