Saint Cloud, MN, United States
Saint Cloud, MN, United States

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Papas K.K.,University of Arizona | Papas K.K.,University of Minnesota | Papas K.K.,Schulze Diabetes Institute | Bellin M.D.,University of Minnesota | And 28 more authors.
PLoS ONE | Year: 2015

Background Reliable in vitro islet quality assessment assays that can be performed routinely, prospectively, and are able to predict clinical transplant outcomes are needed. In this paper we present data on the utility of an assay based on cellular oxygen consumption rate (OCR) in predicting clinical islet autotransplant (IAT) insulin independence (II). IAT is an attractive model for evaluating characterization assays regarding their utility in predicting II due to an absence of confounding factors such as immune rejection and immunosuppressant toxicity. Methods Membrane integrity staining (FDA/PI), OCR normalized to DNA (OCR/DNA), islet equivalent (IE) and OCR (viable IE) normalized to recipient body weight (IE dose and OCR dose), and OCR/DNA normalized to islet size index (ISI) were used to characterize autoislet preparations (n = 35). Correlation between pre-IAT islet product characteristics and II was determined using receiver operating characteristic analysis. Results Preparations that resulted in II had significantly higher OCR dose and IE dose (p<0.001). These islet characterization methods were highly correlated with II at 6-12 months post- IAT (area-under-the-curve (AUC) = 0.94 for IE dose and 0.96 for OCR dose). FDA/PI (AUC = 0.49) and OCR/DNA (AUC = 0.58) did not correlate with II. OCR/DNA/ISI may have some utility in predicting outcome (AUC = 0.72). Conclusions Commonly used assays to determine whether a clinical islet preparation is of high quality prior to transplantation are greatly lacking in sensitivity and specificity. While IE dose is highly predictive, it does not take into account islet cell quality. OCR dose, which takes into consideration both islet cell quality and quantity, may enable a more accurate and prospective evaluation of clinical islet preparations. Copyright: © 2015 Papas et al.

Bellin M.D.,Schulze Diabetes Institute | Bellin M.D.,University of Minnesota | Beilman G.J.,University of Minnesota | Dunn T.B.,University of Minnesota | And 11 more authors.
Pancreas | Year: 2013

Objective: Islet autotransplantation (IAT) is performed in nondiabetic patients with chronic pancreatitis at the time of total pancreatectomy (TP) to minimize risk of postoperative diabetes. The role of TP-IAT in patients with chronic pancreatitis and C-peptide-positive diabetes is not established. We postulate that IAT can preserve beta cell mass and thereby benefit patients with preexisting diabetes undergoing TP. METHODS: Preoperative metabolic testing, islet isolation outcomes, and subsequent islet graft function were reviewed for 27 patients with diabetes mellitus and chronic pancreatitis undergoing TP-IAT. The relationships between the results of preoperative metabolic testing and islet isolation outcomes were explored using regression analysis. RESULTS: Mean islet yield was 2060 (SD, 2408) islet equivalents/kg. Peak C-peptide (from mixed meal tolerance testing) was the strongest predictor of islet yield, with higher stimulated C-peptide levels associated with greater islet mass. Half of the patients who had C-peptide levels measured after transplantation demonstrated C-peptide production at a level that conveys protective benefit in type 1 diabetes (≥0.6 ng/mL). CONCLUSIONS: These findings provide proof of concept that significant islet mass can be isolated in patients with chronic pancreatitis and C-peptide-positive diabetes mellitus undergoing TP-IAT. Stimulated C-peptide may be a useful marker of islet mass before transplantation in these patients. Copyright © 2013 Lippincott Williams & Wilkins.

Sutherland D.E.R.,Schulze Diabetes Institute | Sutherland D.E.R.,University of Minnesota | Radosevich D.M.,University of Minnesota | Bellin M.D.,Schulze Diabetes Institute | And 11 more authors.
Journal of the American College of Surgeons | Year: 2012

Background: Total pancreatectomy (TP) with intraportal islet autotransplantation (IAT) can relieve pain and preserve β-cell mass in patients with chronic pancreatitis (CP) when other therapies fail. We report on a >30-year single-center series. Study Design: Four hundred and nine patients (including 53 children, 5 to 18 years) with CP underwent TP-IAT from February 1977 to September 2011 (etiology: idiopathic, 41%; Sphincter of Oddi dysfunction/biliary, 9%; genetic, 14%; divisum, 17%; alcohol, 7%; and other, 12%; mean age was 35.3 years, 74% were female; 21% has earlier operations, including 9% Puestow procedure, 6% Whipple, 7% distal pancreatectomy, and 2% other). Islet function was classified as insulin independent for those on no insulin; partial, if known C-peptide positive or euglycemic on once-daily insulin; and insulin dependent if on standard basalbolus diabetic regimen. A 36-item Short Form (SF-36) survey for quality of life was completed by patients before and in serial follow-up since 2007, with an integrated survey that was added in 2008. Results: Actuarial patient survival post TP-IAT was 96% in adults and 98% in children (1 year) and 89% and 98% (5 years). Complications requiring relaparotomy occurred in 15.9% and bleeding (9.5%) was the most common complication. IAT function was achieved in 90% (C-peptide >0.6 ng/mL). At 3 years, 30% were insulin independent (25% in adults, 55% in children) and 33% had partial function. Mean hemoglobin A1c was <7.0% in 82%. Earlier pancreas surgery lowered islet yield (2,712 vs 4,077/kg; p = 0.003). Islet yield (<2,500/kg [36%]; 2,501 to 5,000/kg [39%]; >5,000/kg [24%]) correlated with degree of function with insulin-independent rates at 3 years of 12%, 22%, and 72%, and rates of partial function 33%, 62%, and 24%. All patients had pain before TP-IAT and nearly all were on daily narcotics. After TP-IAT, 85% had pain improvement. By 2 years, 59% had ceased narcotics. All children were on narcotics before, 39% at follow-up; pain improved in 94%; and 67% became pain-free. In the SF-36 survey, there was significant improvement from baseline in all dimensions, including the Physical and Mental Component Summaries (p < 0.01), whether on narcotics or not. Conclusions: TP can ameliorate pain and improve quality of life in otherwise refractory CP patients, even if narcotic withdrawal is delayed or incomplete because of earlier long-term use. IAT preserves meaningful islet function in most patients and substantial islet function in more than two thirds of patients, with insulin independence occurring in one quarter of adults and half the children. © 2012 by the American College of Surgeons.

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