title: Islet neogenesis-associated protein-related pentadecapeptide enhances the differentiation of islet-like clusters from human pancreatic duct cells.
abstract: The differentiation of pancreatic ductal epithelial cells into beta-cells has been considered as an alternative method for increasing the number of islets for transplantation. Critical factors have been introduced into the in vitro differentiation protocol for pancreatic duct cells in order to enhance the production of beta-cells. Islet neogenesis-associated protein (INGAP) is an initiator of islet neogenesis and the peptide sequence 104-118 of INGAP has been shown to stimulate an increase in beta-cell mass in animals and also found in human pathological states involving islet neogenesis. To establish a novel method for the differentiation of beta-cells from human pancreatic duct cells with INGAP-related pentadecapeptide (INGAP-PP), the pancreatic duct cells were isolated, purified and expanded in vitro and differentiated using a four-step protocol that included nicotinamide, exendin-4, transforming growth factor beta(1) and INGAP-PP/Scrambled peptide (Scrambled-P). The production of islet-like clusters (ILCs) in the INGAP-PP group was significantly higher than that in the Scrambled-P control group after differentiation from an equal number of duct cells. The duct cells showed positive staining and expression for cytokeratin 19, pancreatic duodenal homeobox-1, nestin, and were negative for insulin and glucagon, as detected by both immunofluorescence and RT-PCR. Following differentiation the cells became insulin and glucagon positive. In addition, the ILCs from the INGAP-PP group secreted higher levels of insulin and C-peptide than the Scrambled-P group under a high glucose challenge. We conclude that INGAP peptide enhances the in vitro differentiation of pancreatic duct cells into islet-like clusters.
authors.affiliation: Department of Endocrinology, The First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing, 210029 Jiangsu, China.
authors.forename: Juan
authors.initials: J
authors.lastname: Li
authors.forename: Yun
authors.initials: Y
authors.lastname: Wang
authors.forename: Xiaozhu
authors.initials: X
authors.lastname: Yu
authors.forename: Haiyan
authors.initials: H
authors.lastname: Chen
authors.forename: Ying
authors.initials: Y
authors.lastname: Wu
authors.forename: Xiao
authors.initials: X
authors.lastname: Han
authors.forename: Xirong
authors.initials: X
authors.lastname: Guo
authors.forename: Chenyu
authors.initials: C
authors.lastname: Zhang
authors.forename: Qi
authors.initials: Q
authors.lastname: Chen
authors.forename: Jiawei
authors.initials: J
authors.lastname: Chen
authors.forename: Tao
authors.initials: T
authors.lastname: Yang
mesh_terms: D000951:Antigens, Neoplasm / Q000737:chemistry*; D014408:Biomarkers, Tumor / Q000737:chemistry*; D002096:C-Peptide / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects; D002478:Cells, Cultured; D005455:Fluorescent Antibody Technique; D005947:Glucose / Q000494:pharmacology; D006801:Humans; D007328:Insulin / Q000378:metabolism; D007381:Intermediate Filament Proteins / Q000235:genetics / Q000378:metabolism; D053539:Keratin-19 / Q000235:genetics / Q000378:metabolism; D037181:Lectins, C-Type / Q000737:chemistry*; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism; D064231:Nestin; D010183:Pancreatic Ducts / Q000166:cytology* / Q000187:drug effects* / Q000378:metabolism*; D000073718:Pancreatitis-Associated Proteins; D010455:Peptides / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology*; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D002096:C-Peptide; D007328:Insulin; D007381:Intermediate Filament Proteins; D053539:Keratin-19; D037181:Lectins, C-Type; C577484:NES protein, human; D009419:Nerve Tissue Proteins; D064231:Nestin; D000073718:Pancreatitis-Associated Proteins; D010455:Peptides; C000612141:REG3A protein, human; D005947:Glucose