Cross‐validation of commercial enzyme‐linked immunosorbent assay and radioimmunoassay for porcine C‐peptide concentration measurements in non‐human primate serum

Background C‐peptide concentration is widely used as a marker of insulin secretion and is especially relevant in evaluating islet graft function following transplantation, because its measurement is not confounded by the presence of exogenous insulin. To address the shortage of human islet donors, t...

Full description

Saved in:
Bibliographic Details
Published in:Xenotransplantation (Københaven) 2017-09, Vol.24 (5), p.n/a
Main Authors: Gresch, Sarah C., Mutch, Lucas A., Janecek, Jody L., Hegstad‐Davies, Rebecca L., Graham, Melanie L.
Format: Article
Language:English
Subjects:
Clinical trials
C‐peptide
Diabetes
Diabetes mellitus
Enzyme-linked immunosorbent assay
Enzymes
Insulin
Islet cells
non‐human primate
Pancreatic islet transplantation
Peptides
Radioimmunoassay
Transplantation
validation
Xenografts
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Background C‐peptide concentration is widely used as a marker of insulin secretion and is especially relevant in evaluating islet graft function following transplantation, because its measurement is not confounded by the presence of exogenous insulin. To address the shortage of human islet donors, the use of porcine islets has been proposed as a possible solution and the stringent pig‐to‐non‐human primate (NHP) model is often the most relevant for pre‐clinical evaluation of the potential for diabetes reversal resulting from an islet xenograft. The Millipore radioimmunoassay (RIA) was exclusively used to measure porcine C‐peptide (PCP) until 2013 when the assay was discontinued and subsequently a commercially available enzyme‐linked immunosorbent assay (ELISA) from Mercodia has been widely adopted. Both assays have been used in pre‐clinical trials evaluating the therapeutic potential of xenograft products in reversing diabetes in the pig‐to‐NHP model, to interpret data in a comparable way it may be useful to perform a harmonization of C‐peptide measurements. Methods We performed a method comparison by determining the PCP concentration in 620 serum samples collected from 20 diabetic cynomolgus macaques transplanted with adult porcine islets. All analyses were performed according to manufacturer instructions. Results With both assays, we demonstrated an acceptable detection limit, precision, and recovery. Linearity of the ELISA met acceptance criteria at all concentrations tested while linearity of the RIA only met acceptance criteria at five of the eight concentrations tested. The RIA had a detection limit of 0.16 ng/mL, and recovery ranged from 82% to 96% and met linearity acceptance criteria at 0.35 ng/mL and from 0.78 to 2.33 ng/mL. The ELISA had a detection limit of 0.03 ng/mL, and recovery ranged from 81% to 115% and met linearity acceptance criteria from 0.08 to 0.85 ng/mL. Both assays had intra‐assay precision
ISSN:0908-665X
1399-3089
DOI:10.1111/xen.12320