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Beta cells within single human islets originate from multiple progenitors.

Scharfmann R, Xiao X, Heimberg H, Mallet J, Ravassard P - PLoS ONE (2008)

Bottom Line: By performing gene transfer at low multiplicity of infection, we created a chimeric graft with a subpopulation of human beta cells expressing GFP and found both GFP-positive and GFP-negative beta cells within single islets.The detection of both labeled and unlabeled beta cells in single islets demonstrates that beta cells present in a human islet are derived from multiple progenitors thus providing the first dynamic analysis of human islet formation during development.This human transgenic-like tool can be widely used to elucidate dynamic genetic processes in human tissue formation.

View Article: PubMed Central - PubMed

Affiliation: University Paris-Descartes, Faculty of Medicine, INSERM, Necker Hospital, U845, Paris, France.

ABSTRACT

Background: In both humans and rodents, glucose homeostasis is controlled by micro-organs called islets of Langerhans composed of beta cells, associated with other endocrine cell types. Most of our understanding of islet cell differentiation and morphogenesis is derived from rodent developmental studies. However, little is known about human islet formation. The lack of adequate experimental models has restricted the study of human pancreatic development to the histological analysis of different stages of pancreatic development. Our objective was to develop a new experimental model to (i) transfer genes into developing human pancreatic cells and (ii) validate gene transfer by defining the clonality of developing human islets.

Methods and findings: In this study, a unique model was developed combining ex vivo organogenesis from human fetal pancreatic tissue and cell type-specific lentivirus-mediated gene transfer. Human pancreatic progenitors were transduced with lentiviruses expressing GFP under the control of an insulin promoter and grafted to severe combined immunodeficient mice, allowing human beta cell differentiation and islet morphogenesis. By performing gene transfer at low multiplicity of infection, we created a chimeric graft with a subpopulation of human beta cells expressing GFP and found both GFP-positive and GFP-negative beta cells within single islets.

Conclusion: The detection of both labeled and unlabeled beta cells in single islets demonstrates that beta cells present in a human islet are derived from multiple progenitors thus providing the first dynamic analysis of human islet formation during development. This human transgenic-like tool can be widely used to elucidate dynamic genetic processes in human tissue formation.

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Cytoarchitecture of newly formed islets from human fetal pancreas.A–C: Section of adult mouse pancreas stained for glucagon (green) and insulin (red). D–F: Section of an adult human pancreas stained for glucagon (green) and insulin (red). G–I: Section of a human fetal pancreas analyzed 4.5 months after transplantation and stained for glucagon (green) and insulin (red). Nuclear staining (blue) was performed with DAPI. Scale bars: 25 µm.
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pone-0003559-g001: Cytoarchitecture of newly formed islets from human fetal pancreas.A–C: Section of adult mouse pancreas stained for glucagon (green) and insulin (red). D–F: Section of an adult human pancreas stained for glucagon (green) and insulin (red). G–I: Section of a human fetal pancreas analyzed 4.5 months after transplantation and stained for glucagon (green) and insulin (red). Nuclear staining (blue) was performed with DAPI. Scale bars: 25 µm.

Mentions: In human fetuses, the first insulin-positive cells appear between seven and eight weeks of development; these cells go on to associate to form islets of Langerhans [17]–[19]. We have previously shown that islet formation occurs when human fetal pancreases are grafted under the kidney capsule of scid mice [16], [20]. In this study, we first compared the cyto-architecture of islets that developed from human fetal pancreas transplanted in scid mice to that of islets found in human and mouse pancreas. Adult mouse islets are composed of an insulin-positive cell core surrounded by glucagon-expressing cells (Fig. 1, Panels A–C), whereas in human adult islets (Fig. 1, panels D–F), glucagon-expressing cells are scattered throughout the islets [13], [21]. In our study, the distribution of insulin- and glucagon-positive cells within a human islet 4.5 months after transplantation was very similar to that observed for human adult pancreatic islets (Fig. 1 compare panel G–I to D–F).


Beta cells within single human islets originate from multiple progenitors.

Scharfmann R, Xiao X, Heimberg H, Mallet J, Ravassard P - PLoS ONE (2008)

Cytoarchitecture of newly formed islets from human fetal pancreas.A–C: Section of adult mouse pancreas stained for glucagon (green) and insulin (red). D–F: Section of an adult human pancreas stained for glucagon (green) and insulin (red). G–I: Section of a human fetal pancreas analyzed 4.5 months after transplantation and stained for glucagon (green) and insulin (red). Nuclear staining (blue) was performed with DAPI. Scale bars: 25 µm.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2571119&req=5

pone-0003559-g001: Cytoarchitecture of newly formed islets from human fetal pancreas.A–C: Section of adult mouse pancreas stained for glucagon (green) and insulin (red). D–F: Section of an adult human pancreas stained for glucagon (green) and insulin (red). G–I: Section of a human fetal pancreas analyzed 4.5 months after transplantation and stained for glucagon (green) and insulin (red). Nuclear staining (blue) was performed with DAPI. Scale bars: 25 µm.
Mentions: In human fetuses, the first insulin-positive cells appear between seven and eight weeks of development; these cells go on to associate to form islets of Langerhans [17]–[19]. We have previously shown that islet formation occurs when human fetal pancreases are grafted under the kidney capsule of scid mice [16], [20]. In this study, we first compared the cyto-architecture of islets that developed from human fetal pancreas transplanted in scid mice to that of islets found in human and mouse pancreas. Adult mouse islets are composed of an insulin-positive cell core surrounded by glucagon-expressing cells (Fig. 1, Panels A–C), whereas in human adult islets (Fig. 1, panels D–F), glucagon-expressing cells are scattered throughout the islets [13], [21]. In our study, the distribution of insulin- and glucagon-positive cells within a human islet 4.5 months after transplantation was very similar to that observed for human adult pancreatic islets (Fig. 1 compare panel G–I to D–F).

Bottom Line: By performing gene transfer at low multiplicity of infection, we created a chimeric graft with a subpopulation of human beta cells expressing GFP and found both GFP-positive and GFP-negative beta cells within single islets.The detection of both labeled and unlabeled beta cells in single islets demonstrates that beta cells present in a human islet are derived from multiple progenitors thus providing the first dynamic analysis of human islet formation during development.This human transgenic-like tool can be widely used to elucidate dynamic genetic processes in human tissue formation.

View Article: PubMed Central - PubMed

Affiliation: University Paris-Descartes, Faculty of Medicine, INSERM, Necker Hospital, U845, Paris, France.

ABSTRACT

Background: In both humans and rodents, glucose homeostasis is controlled by micro-organs called islets of Langerhans composed of beta cells, associated with other endocrine cell types. Most of our understanding of islet cell differentiation and morphogenesis is derived from rodent developmental studies. However, little is known about human islet formation. The lack of adequate experimental models has restricted the study of human pancreatic development to the histological analysis of different stages of pancreatic development. Our objective was to develop a new experimental model to (i) transfer genes into developing human pancreatic cells and (ii) validate gene transfer by defining the clonality of developing human islets.

Methods and findings: In this study, a unique model was developed combining ex vivo organogenesis from human fetal pancreatic tissue and cell type-specific lentivirus-mediated gene transfer. Human pancreatic progenitors were transduced with lentiviruses expressing GFP under the control of an insulin promoter and grafted to severe combined immunodeficient mice, allowing human beta cell differentiation and islet morphogenesis. By performing gene transfer at low multiplicity of infection, we created a chimeric graft with a subpopulation of human beta cells expressing GFP and found both GFP-positive and GFP-negative beta cells within single islets.

Conclusion: The detection of both labeled and unlabeled beta cells in single islets demonstrates that beta cells present in a human islet are derived from multiple progenitors thus providing the first dynamic analysis of human islet formation during development. This human transgenic-like tool can be widely used to elucidate dynamic genetic processes in human tissue formation.

Show MeSH
Related in: MedlinePlus