Transplantation of 3D Scaffolds Seeded with Human Embryonic Stem Cells: Biological Features of Surrogate Tissue and Teratoma-Forming Potential

Abstract

Aim:To generate complex surrogate tissue by transplanting 3D scaffolds seeded with human embryonic stem cells (hESCs) between the liver lobules of severe combined immunodeficient (SCID) mice and to assess the teratoma-forming potential. Materials & methods: 3D poly-(lactic-co-glycolic acid) (PLGA) scaffolds coated with laminin were seeded with hESCs and then transplanted between the liver lobules of SCID mice. After a period of in vivo differentiation, the scaffolds were retrieved and analyzed using reverse transcription polymerase chain reaction, immunofluorescent staining and scanning electron microscopy. Results: A proportion of the hESCs within the scaffolds differentiated into cells that produced proteins characteristic of specific tissues, including endoderm and pancreatic markers glucogon-like peptide-1 receptor, islet amyloid polypeptide and Insulin. Markers of hepatic and neuronal lineages were also investigated. Major matrix proteins abundant in multiple tissue types, including collagen I, laminin and collagen IV, were found to be profuse within the scaffold pores. Transplantation of the seeded scaffolds between liver lobules also resulted in extensive vascularization both from host blood vessel incursion and the differentiation of hESCs into endothelial progenitor cells. An investigation of teratomaforming potential demonstrated that transplantation of 3D scaffolds seeded with hESCs will, under certain conditions, lead to the growth of teratomas. Discussion: Transplantation of 3D scaffolds seeded with hESCs between liver lobules resulted in the development of surrogate tissue containing cells that produced proteins representing the pancreatic, hepatic and neuronal lineages, the assembly of an extracellular matrix structure and the formation of a vasculature. hESCs seeded within 3D scaffolds and transplanted into SCID mice were capable of forming teratomas. However, the formation and progression of teratoma growth is shown to be dependant on both the site of transplantation and the treatment of cells prior to transplantation.

Efficient Generation of Human Embryonic Stem Cell-Derived Cardiac Progenitors Based on Tissue-Specific Enhanced Green Fluorescence Protein Expression

“…Using precursor cells seemed the best choice, as undifferentiated hESCs, besides the differentiation into the desired cell population, formed teratomas, 33 while transplantation of differentiated motor neurons showed only limited functional recovery. 34 Cardiac progenitors have been applied in transplantational studies as well, either in the form of cell suspension 35 or as engineered cardiac patches 2 to improve the modest functional benefit of existing transplantation strategies.…”

In Vivo Bone Formation by Progeny of Human Embryonic Stem Cells

“…It was suggested earlier that to eradicate teratoma formation by hESC-derived cells, period of their cultivation in differentiating conditions should be >2 weeks, thus allowing them to differentiate beyond the pluripotent phenotype [69]. We cultured HSF-6-derived strains in various differentiating conditions for much longer periods, ranging from 7 to 14.5 weeks.…”

Retracted:Promoting the Recovery of Injured Liver with Poly (3-Hydroxybutyrate-Co-3-Hydroxyvalerate-Co-3-Hydroxyhexanoate) Scaffolds Loaded with Umbilical Cord-Derived Mesenchymal Stem Cells

“…2 Three-dimensional biocompatible scaffolds can provide a supporting structure for cell growth, facilitate the cell-cell and cell-matrix interactions, and have a promoting effect on cell attachment and differentiation. 3,4 Finding a suitable scaffold plays an important role in tissue engineering. Polyhydroxyalkanoate (PHA) is a family of polyesters produced by bacteria under unbalanced growth conditions.…”