Related Experiment Video
Updated: Dec 30, 2025
Measurement of Differentially Methylated INS DNA Species in Human Serum Samples as a Biomarker of Islet β Cell Death
Published on: December 21, 2016
Epigenetic biomarkers indicate islet cell death in xenotransplantation
Christopher Faulk1, Kate R Mueller2, David Cheishvili3
1Department of Animal Sciences, College of Food, Agricultural and Natural Resource Sciences, University of Minnesota, Saint Paul, MN, USA.
Background:
Xenotransplantation of porcine islets has emerged in recent decades as a potential treatment for type 1 diabetes (T1D). Current methods of detection, indicative of successful engraftment, occur downstream of actual islet death. Epigenetic biomarkers can be detected in circulating cell-free DNA (cfDNA) to provide an earlier indication of graft dysfunction.
Aims:
The present study identified a biomarker of islet death using differential methylation of the insulin gene, INS, originating from β-cells in porcine islets.
Materials & Methods:
Pyrosequencing primers specific for porcine INS were designed to quantify hypomethylation along 12 cysteine-guanine dinucleotide (CpG) sites, including three sites in the cyclic adenosine monophosphate (cAMP) response element (CRE) binding protein 2 (CRE2) binding region of the 5' untranslated region (UTR) and nine sites within intron 2.
Results:
PCR amplification of bisulfite-converted DNA combined with pyrosequencing data support the conclusion that hypomethylated porcine INS is specific to islet origin.
Conclusion:
Moreover, the results of this study indicate a highly specific epigenetic biomarker, capable of detecting a single islet, supporting the measurement of cfDNA as a biomarker for transplanted islet death. Defining the epigenetic characteristics of porcine-derived islets within cfDNA will be crucial to develop a better understanding of graft survival immunology for transplantation.
