OBJECTIVEThe contribution of innate immunity responsible for aggressive β-cell destruction in human fulminant type 1 diabetes is unclear.RESEARCH DESIGN AND METHODSIslet cell expression of Toll-like receptors (TLRs), cytoplasmic retinoic acid–inducible gene I (RIG-I)-like receptors, downstream innate immune markers, adaptive immune mediators, and apoptotic markers was studied in three autopsied pancreata obtained 2 to 5 days after onset of fulminant type 1 diabetes.RESULTSRIG-I was strongly expressed in β-cells in all three pancreata infected with enterovirus. Melanoma differentiation–associated gene-5 was hyperexpressed in islet cells, including β- and α-cells. TLR3 and TLR4 were expressed in mononuclear cells that infiltrated islets. Interferon (IFN)-α and IFN-β were strongly expressed in islet cells. Major histocompatibility complex (MHC)-class I, IFN-γ, interleukin-18, and CXC motif ligand 10 were expressed and colocalized in affected islets. CD11c+ MHC-class II+ dendritic cells and macrophage subsets infiltrated most islets and showed remarkable features of phagocytosis of islet cell debris. CD4+ forkhead box P3+ regulatory T cells were not observed in and around the affected islets. Mononuclear cells expressed the Fas ligand and infiltrated most Fas-expressing islets. Retinoic acid–receptor responder 3 and activated caspases 8, 9, and 3 were preferentially expressed in β-cells. Serum levels of IFN-γ were markedly increased in patients with fulminant type 1 diabetes.CONCLUSIONSThese findings demonstrate the presence of specific innate immune responses to enterovirus infection connected with enhanced adoptive immune pathways responsible for aggressive β-cell toxicity in fulminant type 1 diabetes.

In chronic kidney disease (CKD) patients, inflammation plays a pivotal role in the progression of renal fibrosis. Hypothyroidism is associated with an increased occurrence of atherosclerosis and inflammation, suggesting protective roles of thyroid hormones and their receptors against inflammatory processes. The contribution of thyroid hormone receptors to macrophage differentiation has not been well documented. Here, we focused on the endogenous thyroid hormone receptor α (TRα) in macrophages and examined the role of ligand-bound TRα in macrophage polarization-mediated anti-inflammatory effects. TRα-deficient irradiated chimeric mice showed exacerbated tubulointerstitial injury in a unilateral ureteral obstruction model. Compared with wild-type macrophages, macrophages isolated from the obstructed kidneys of mice lacking TRα displayed increased expression of proinflammatory cytokines that was accompanied by enhanced nuclear translocation of p65. Comparison of TRα-deficient bone marrow-derived macrophages with wild-type macrophages confirmed the propensity of the former cells to produce excessive IL-1β levels. Co-culture of these macrophages with renal epithelial cells induced more severe damage to the epithelial cells via the IL-1 receptor. Our findings indicate that ligand-bound TRα on macrophages plays a protective role in kidney inflammation through the inhibition of NF-κB pathways, possibly by affecting the pro- and anti-inflammatory balance that controls the development of CKD.

BackgroundPancreatic islet endocrine cell-supporting architectures, including islet encapsulating basement membranes (BMs), extracellular matrix (ECM), and possible cell clusters, are unclear.ProceduresThe architectures around islet cell clusters, including BMs, ECM, and pancreatic acinar-like cell clusters, were studied in the non-diabetic state and in the inflamed milieu of fulminant type 1 diabetes in humans.ResultImmunohistochemical and electron microscopy analyses demonstrated that human islet cell clusters and acinar-like cell clusters adhere directly to each other with desmosomal structures and coated-pit-like structures between the two cell clusters. The two cell-clusters are encapsulated by a continuous capsule composed of common BMs/ECM. The acinar-like cell clusters have vesicles containing regenerating (REG) Iα protein. The vesicles containing REG Iα protein are directly secreted to islet cells. In the inflamed milieu of fulminant type 1 diabetes, the acinar-like cell clusters over-expressed REG Iα protein. Islet endocrine cells, including beta-cells and non-beta cells, which were packed with the acinar-like cell clusters, show self-replication with a markedly increased number of Ki67-positive cells.ConclusionThe acinar-like cell clusters touching islet endocrine cells are distinct, because the cell clusters are packed with pancreatic islet clusters and surrounded by common BMs/ECM. Furthermore, the acinar-like cell clusters express REG Iα protein and secrete directly to neighboring islet endocrine cells in the non-diabetic state, and the cell clusters over-express REG Iα in the inflamed milieu of fulminant type 1 diabetes with marked self-replication of islet cells.

Large quantities of radionuclides have leaked from the Fukushima Daiichi Nuclear Power Plant into the surrounding environment. Effective prevention of health hazards resulting from radiation exposure will require the development of efficient and economical methods for decontaminating radioactive wastewater and aquatic ecosystems. Here we describe the accumulation of water-soluble radionuclides released by nuclear reactors by a novel strain of alga. The newly discovered green microalgae, Parachlorella sp. binos (Binos) has a thick alginate-containing extracellular matrix and abundant chloroplasts. When this strain was cultured with radioiodine, a light-dependent uptake of radioiodine was observed. In dark conditions, radioiodine uptake was induced by addition of hydrogen superoxide. High-resolution secondary ion mass spectrometry (SIMS) showed a localization of accumulated iodine in the cytosol. This alga also exhibited highly efficient incorporation of the radioactive isotopes strontium and cesium in a light-independent manner. SIMS analysis showed that strontium was distributed in the extracellular matrix of Binos. Finally we also showed the ability of this strain to accumulate radioactive nuclides from water and soil samples collected from a heavily contaminated area in Fukushima. Our results demonstrate that Binos could be applied to the decontamination of iodine, strontium and cesium radioisotopes, which are most commonly encountered after nuclear reactor accidents.

Aims Whether the titer of glutamic acid decarboxylase antibodies (GADAs), especially a low titer, is a marker of progression of beta cell dysfunction in patients with slowly progressive insulin-dependent (type 1) diabetes (SPIDDM) is unclear. Materials and methods Patients were subdivided as follows: patients with high GADA titers [C10 U/ml (C180 WHO U/ml): high GADA] (group 1, n = 37); those with low GADA titers [\10 U/ml (\180 WHO U/ml): low GADA] (group 2, n = 33); those without GADA and with islet cell antibodies (ICA) (group 3, n = 8); those without both GADA and ICA and with insulinoma-associated antigen 2 antibodies (IA-2A) (group 4, n = 6). We also allocated 198 type 2 diabetic patients without any GADA, ICA or IA-2A as group 5. Serum C-peptide responses to annual oral glucose tolerance tests (OGTTs) were followed up for a mean of 107 months from entry. Results The proportion of patients progressing to an insulin-dependent state in groups 1, 2, 3 and 4 was significantly higher than in group 5. C-peptide responses in OGTTs of patients in groups 1 and 2 were decreased at a significantly higher rate than in group 5. Multivariate Cox proportional hazard analysis revealed that factors including high GADA, low GADA, onset age \45 years, duration of diabetes \24 months, body mass index (BMI) \22.0 kg/ m 2 , low degree of preserved beta cell function and ICA were independent risk factors for progression to an insulindependent state. Conclusions SPIDDM patients with low GADA titers have a significantly higher risk of progression to an insulindependent state than type 2 diabetic patients, suggesting that the presence of GADA, irrespective of the titer, is a hallmark of beta cell failure. Other risk factors for further progression to an insulin-dependent state in SPIDDM patients were ICA, onset age, duration of diabetes, BMI and residual beta cell function. Keywords Slowly progressive insulin-dependent (type 1) diabetes mellitus Á Glutamic acid decarboxylase antibodies Á Islet cell antibodies Á C-peptide