A promising treatment method for type 1 diabetes mellitus is transplantation of pancreatic islets containing ␤-cells. The aim of this study was to develop an MR technique to monitor the distribution and fate of transplanted pancreatic islets in an animal model. Twenty-five hundred purified and magnetically labeled islets were transplanted through the portal vein into the liver of experimental rats. The animals were scanned using a MR 4.7-T scanner. The labeled pancreatic islets were clearly visualized in the liver in both diabetic and healthy rats as hypointense areas on T 2 *-weighted MR images during the entire measurement period. Transmission electron microscopy confirmed the presence of iron-oxide nanoparticles inside the cells of the pancreatic islets. A significant decrease in blood glucose levels in diabetic rats was observed; normal glycemia was reached 1 week after transplantation. This study, therefore, represents a promising step toward possible clinical application in human medicine.

Background: Microalbuminuria is an early sign of kidney disease in diabetes and indicates cardiovascular risk. We tested if a prespecified urinary proteomic risk classifier (CKD273) was associated with development of microalbuminuria and if progression to microalbuminuria could be prevented with the mineralocorticoid receptor antagonist spironolactone. Methods: Prospective multicentre study in people with type 2 diabetes, normal urinary albumin excretion and preserved renal function in 15 European specialist centres. High-risk individuals determined by CKD273 were randomised 1:1 (interactive web response system) in a double-blind randomised controlled trial comparing spironolactone 25 mg o.d. to placebo. Primary endpoint was development of confirmed microalbuminuria in all individuals with available data. Secondary endpoints included reduction in incidence of microalbuminuria with spironolactone and association between CKD273 and impaired renal function defined as a glomerular filtration rate < 60 ml/min per 1•73 m 2. This study is registered with ClinicalTrials.gov: NCT02040441 and is completed. Findings: From March 25, 2014 to September 30, 2018 we followed 1775 participants, 12% (n=216) had high-risk urinary proteomic pattern of which 209 were included in the trial and assigned spironolactone (n=102) or placebo (n=107). Median follow-up time was 2•51 years (IQR 2•0-3•0). Progression to microalbuminuria was seen in 28•2% of high-risk and 8•9% of low-risk people (P< 0•001) (hazard ratio (HR), 2•48; 95% confidence interval [CI], 1•80 to 3•42 P<0•001, independent of baseline clinical characteristics). A 30% decline in eGFR from baseline was seen in 42 (19•4 %) high-risk participants compared to 62 (3•9 %) low-risk participants, HR 5•15; 95 % CI (3•41 to 7•76; p<0.0001). Development of microalbuminuria was seen in 35 (33%) randomised to placebo and 26 (25%) randomised to spironolactone treatment (HR 0•81, 95% CI, 0•49 to 1•34, P=0•41). Harms: hyperkalaemia was seen in 13 versus 4, and gynaecomastia in 3 versus 0 subjects on spironolactone and placebo, respectively. Interpretation: In people with type 2 diabetes and normoalbuminuria, the urinary proteomic classifier CKD273 was associated with a 2•5 times increased risk for progression to microalbuminuria over a median of 2•5 years, independent of clinical characteristics. Spironolactone did not prevent progression to microalbuminuria in high-risk subjects.

MR imaging of iron-labeled pancreatic islets can be used for verification of the technical success of the transplantation procedure itself and for the detection of the decreasing relative islet mass due to rejection.

Pancreatic islets (PI) visualization was safe and successful in all recipients but was less efficient if labeling period was less than 16 hr. Significant decrease of islet spots occurred at week 1, suggesting early islet destruction or impaired engraftment. Afterward, the islet spot numbers remained stable for up to 24 weeks. Data show that MR detection of ferucarbotran-labeled islets enables their long-term noninvasive visualization and correlates with sustained C-peptide production.

In vitro labeling of pancreatic islets with iron nanoparticles enables their direct posttransplant visualization by magnetic resonance; however, there is still a discrepancy in the fate of iron nanoparticles. This study was performed to detail the labeling process, consequently to improve the labeling efficacy and to confirm safety for islet cells. The islets were visible on T2*-weighted magnetic resonance images as hypointense spots immediately after 1-hr cultivation. Although at this time already the sufficient superparamagnetic effect was achieved, most of the particles were deposed in islet macrophages and only later were they found in endosomes of endocrine islet cells. The iron content depended on length of culture period. The labeled islets showed an intact ultrastructure, responded normally to glucose stimulation in vitro, and were able to treat experimental diabetes. For purpose of subsequent magnetic resonance imaging, a 24-hr culture with ferucarbotran leads to sufficient labeling with no apparent adverse effect on beta cell morphology or function.

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Introduction: Islet transplantation is a promising treatment for type 1 diabetic patients; however, there are several hurdles to make islet cell transplantation as the standard therapy. Early graft loss immediately after islet transplantation caused primarily due to inflammation is one of such issues. Recently we and others demonstrated that IL-1 beta played critical role at the onset of juvenile diabetes. In addition, based on collaborative islet transplant registry (CITR) database, TNF-alpha blockage significantly improved clinical outcome of islet transplantation. Therefore, we hypothesized that combined inflammatory blockade using anakinra (IL-1beta blocker) and etanercept (TNF-alpha blocker) will improve the efficacy of islet transplantation. Methods: Nine clinical grade human pancreata were procured by surgeons who belonged to islet isolation team. Pancreatic ductal preservation was performed using ET-Kyoto solution and oxygen static charged two-layer method was used for transportation of procured pancreata in all cases (Cell Transplantation in press). Islets were isolated using modified Ricordi method. When isolated islet preparation met transplantation criteria based on the Edmonton protocol, we transplanted those islets into type 1 diabetic patients. We used two immunosuppression and anti-inflammatory protocols. The first protocol used daclizumab for induction and sirolimus and tacrolimus for maintenance immunosuppression. Eternacept was administered for anti-inflammation. The second protocol used thymoglobulin for induction and tacrolimus and mycophenolate mofetile for maintenance immunosuppression. Eternacept and anakinra were administered for anti-inflammation. As an assessment of islet transplantation, total amount of insulin requirement and SUITO index were monitored. To assess the efficacy of anti-inflammatory therapy, we performed gene microarray from patients' peripheral blood samples at pre-transplant, post operative day (POD) 1, 2, 4, 7 with the second protocol. Results: All isolated islet preparations met criteria for clinical transplantation; therefore, the success rate of clinical islet isolation was 100% (9/9). Nine clinical islet transplantations were performed into 6 type 1 diabetic patients. All patients achieved insulin independence; however, the first protocol required two islet infusions and the second protocol required only single infusion. Average SUITO index at one month was significantly higher in the second protocol group (52.0±9.6 vs. 27.6±12, p<0.05). Gene microarray analysis revealed that T cell and cytotoxic cell related genes were substantially suppressed. However, inflammation and neutrophil related genes were significantly activated suggesting that the other inflammatory mechanisms besides TNF-alpha and IL-1 beta may be relevant. Platelet related genes were not activated suggesting that current anticoagulation protocol might be enough to prevent coagulation related inflammatory reaction. Conclusion: Combined IL-1beta and TNF-alpha blockage allowed us to achieve insulin-fre...

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