Assessment of simple indices based on a single fasting blood sample as a tool to estimate beta-cell function after total pancreatectomy with islet autotransplantation - a prospective study.

We investigated six indices based on a single fasting blood sample for evaluation of the beta-cell function after total pancreatectomy with islet autotransplantation (TP-IAT). The Secretory Unit of Islet Transplant Objects (SUITO), transplant estimated function (TEF), homeostasis model assessment (HOMA-2B%), C-peptide/glucose ratio (CP/G), C-peptide/glucose creatinine ratio (CP/GCr) and BETA-2 score were compared against a 90-min serum glucose level, weighted mean C-peptide in mixed meal tolerance test (MMTT), beta score and the Igls score adjusted for islet function in the setting of IAT. We analyzed values from 32 MMTTs in 15 patients after TP-IAT with a follow-up of up to 3 years. Four (27%) individuals had discontinued insulin completely prior to day 75, while 6 out of 12 patients (50%) did not require insulin support at 1-year follow-up with HbA1c 6.0% (5.5-6.8). BETA-2 was the most consistent among indices strongly correlating with all reference measures of beta-cell function (r = 0.62-0.68). In addition, it identified insulin independence (cut-off = 16.2) and optimal/good versus marginal islet function in the Igls score well, with AUROC of 0.85 and 0.96, respectively. Based on a single fasting blood sample, BETA-2 score has the most reliable discriminant value for the assessment of graft function in patients undergoing TP-IAT.

National Institutes of Health-Sponsored Clinical Islet Transplantation Consortium Phase 3 Trial: Manufacture of a Complex Cellular Product at Eight Processing Facilities.

Eight manufacturing facilities participating in the National Institutes of Health-sponsored Clinical Islet Transplantation (CIT) Consortium jointly developed and implemented a harmonized process for the manufacture of allogeneic purified human pancreatic islet (PHPI) product evaluated in a phase 3 trial in subjects with type 1 diabetes. Manufacturing was controlled by a common master production batch record, standard operating procedures that included acceptance criteria for deceased donor organ pancreata and critical raw materials, PHPI product specifications, certificate of analysis, and test methods. The process was compliant with Current Good Manufacturing Practices and Current Good Tissue Practices. This report describes the manufacturing process for 75 PHPI clinical lots and summarizes the results, including lot release. The results demonstrate the feasibility of implementing a harmonized process at multiple facilities for the manufacture of a complex cellular product. The quality systems and regulatory and operational strategies developed by the CIT Consortium yielded product lots that met the prespecified characteristics of safety, purity, potency, and identity and were successfully transplanted into 48 subjects. No adverse events attributable to the product and no cases of primary nonfunction were observed.

Engraftment assessment in human and mouse liver tissue after sex-mismatched liver cell transplantation by real-time quantitative PCR for Y chromosome sequences.

Transplanted hepatocytes can engraft, proliferate, and function permanently in host animals. After one cell infusion, however, engrafted hepatocytes constitute only between 1 in 200 to 1 in 3,000 host liver cells. Although transplanted cells can be identified using biochemical and molecular techniques, more accurate methods are needed to evaluate interventions that could improve cell engraftment rates. Real-time polymerase chain reaction (PCR) was done using primers and probes complementary to human testis determining gene (SRY) and mouse testis-specific Y-encoded protein (TSPY) pseudogene. Tissue samples from human or mouse recipients of liver cell transplantation were used to determine the test ability to detect transplanted cell DNA. Real-time PCR for the human SRY and mouse TSPY were species- and sex-specific. These two tests were sensitive in the detection of male DNA. Test sensitivity was consistently found at minimum 1:10,000 of male and female DNA mixing curve in both human SRY and mouse TSPY assays. The optimal amount of sample DNA per reaction to produce the highest sensitivity was 300 ng to 1 microg. Real-time PCR gave similar results whether standard male-female mixtures were prepared from liver cells or mononuclear cells. Engraftment of male liver cells in female liver tissues in mice and humans ranging from 0.125% to 0.257% was successfully measured using this method. Real-time PCR for SRY and TSPY affords a specific, sensitive, and reproducible tool for chimerism analysis in transplanted human and mouse liver tissues. This method could be used to optimize current models of cell transplantation.