In vivo cell reprogramming to pluripotency: exploring a novel tool for cell replenishment and tissue regeneration

The potential of cell-replacement strategies for the treatment of disorders in which a particular cell type is damaged or degenerated has prompted the search for the perfect cell source. iPSCs (induced pluripotent stem cells) stand out as very advantageous candidates thanks to their self-renewal capacity and differentiation potential, together with the possibility of generating them from autologous somatic cells with minimally invasive techniques. However, their differentiation into the required cell type, precise delivery and successful engraftment and survival in the host are still challenging. We have proposed the transient reprogramming of somatic cells towards a pluripotent state in their in vivo microenvironment as a means to facilitate the regeneration of the tissue. The initial reports of in vivo reprogramming to pluripotency in the literature are reviewed and the potential clinical applications of this strategy are discussed.

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Exogenous LIN28 Is Required for the Maintenance of Self-Renewal and Pluripotency in Presumptive Porcine-Induced Pluripotent Stem Cells

Frontiers in Cell and Developmental Biology ◽

10.3389/fcell.2021.709286 ◽

2021 ◽

Vol 9 ◽

Author(s):

Warunya Chakritbudsabong ◽

Somjit Chaiwattanarungruengpaisan ◽

Ladawan Sariya ◽

Sirikron Pamonsupornvichit ◽

Joao N. Ferreira ◽

...

Keyword(s):

Stem Cells ◽

Alkaline Phosphatase ◽

Induced Pluripotent Stem Cells ◽

Pluripotent Stem Cells ◽

Embryoid Bodies ◽

Self Renewal ◽

Fetal Fibroblasts ◽

Induced Pluripotent

Porcine species have been used in preclinical transplantation models for assessing the efficiency and safety of transplants before their application in human trials. Porcine-induced pluripotent stem cells (piPSCs) are traditionally established using four transcription factors (4TF): OCT4, SOX2, KLF4, and C-MYC. However, the inefficiencies in the reprogramming of piPSCs and the maintenance of their self-renewal and pluripotency remain challenges to be resolved. LIN28 was demonstrated to play a vital role in the induction of pluripotency in humans. To investigate whether this factor is similarly required by piPSCs, the effects of adding LIN28 to the 4TF induction method (5F approach) on the efficiency of piPSC reprogramming and maintenance of self-renewal and pluripotency were examined. Using a retroviral vector, porcine fetal fibroblasts were transfected with human OCT4, SOX2, KLF4, and C-MYC with or without LIN28. The colony morphology and chromosomal stability of these piPSC lines were examined and their pluripotency properties were characterized by investigating both their expression of pluripotency-associated genes and proteins and in vitro and in vivo differentiation capabilities. Alkaline phosphatase assay revealed the reprogramming efficiencies to be 0.33 and 0.17% for the 4TF and 5TF approaches, respectively, but the maintenance of self-renewal and pluripotency until passage 40 was 6.67 and 100%, respectively. Most of the 4TF-piPSC colonies were flat in shape, showed weak positivity for alkaline phosphatase, and expressed a significantly high level of SSEA-4 protein, except for one cell line (VSMUi001-A) whose properties were similar to those of the 5TF-piPSCs; that is, tightly packed and dome-like in shape, markedly positive for alkaline phosphatase, and expressing endogenous pluripotency genes (pOCT4, pSOX2, pNANOG, and pLIN28), significantly high levels of pluripotent proteins (OCT4, SOX2, NANOG, LIN28, and SSEA-1), and a significantly low level of SSEA-4 protein. VSMUi001-A and all 5F-piPSC lines formed embryoid bodies, underwent spontaneous cardiogenic differentiation with cardiac beating, expressed cardiomyocyte markers, and developed teratomas. In conclusion, in addition to the 4TF, LIN28 is required for the effective induction of piPSCs and the maintenance of their long-term self-renewal and pluripotency toward the development of all germ layers. These piPSCs have the potential applicability for veterinary science.

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Transgene Delivery to Human Induced Pluripotent Stem Cells Using Nanoparticles

Pharmaceuticals ◽

10.3390/ph14040334 ◽

2021 ◽

Vol 14 (4) ◽

pp. 334

Author(s):

Megan A. Yamoah ◽

Phung N. Thai ◽

Xiao-Dong Zhang

Keyword(s):

Stem Cells ◽

Induced Pluripotent Stem Cells ◽

Genetic Modification ◽

Pluripotent Stem Cells ◽

High Efficiency ◽

Low Cost ◽

Somatic Cells ◽

Transgene Delivery ◽

Induced Pluripotent

Human induced pluripotent stem cells (hiPSCs) and hiPSCs-derived cells have the potential to revolutionize regenerative and precision medicine. Genetically reprograming somatic cells to generate hiPSCs and genetic modification of hiPSCs are considered the key procedures for the study and application of hiPSCs. However, there are significant technical challenges for transgene delivery into somatic cells and hiPSCs since these cells are known to be difficult to transfect. The existing methods, such as viral transduction and chemical transfection, may introduce significant alternations to hiPSC culture which affect the potency, purity, consistency, safety, and functional capacity of hiPSCs. Therefore, generation and genetic modification of hiPSCs through non-viral approaches are necessary and desirable. Nanotechnology has revolutionized fields from astrophysics to biology over the past two decades. Increasingly, nanoparticles have been used in biomedicine as powerful tools for transgene and drug delivery, imaging, diagnostics, and therapeutics. The most successful example is the recent development of SARS-CoV-2 vaccines at warp speed to combat the 2019 coronavirus disease (COVID-19), which brought nanoparticles to the center stage of biomedicine and demonstrated the efficient nanoparticle-mediated transgene delivery into human body. Nanoparticles have the potential to facilitate the transgene delivery into the hiPSCs and offer a simple and robust approach. Nanoparticle-mediated transgene delivery has significant advantages over other methods, such as high efficiency, low cytotoxicity, biodegradability, low cost, directional and distal controllability, efficient in vivo applications, and lack of immune responses. Our recent study using magnetic nanoparticles for transfection of hiPSCs provided an example of the successful applications, supporting the potential roles of nanoparticles in hiPSC biology. This review discusses the principle, applications, and significance of nanoparticles in the transgene delivery to hiPSCs and their successful application in the development of COVID-19 vaccines.

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Cell Type-Specific Chromatin Signatures Underline Regulatory DNA Elements in Human Induced Pluripotent Stem Cells and Somatic Cells

Circulation Research ◽

10.1161/circresaha.117.311367 ◽

2017 ◽

Vol 121 (11) ◽

pp. 1237-1250 ◽

Cited By ~ 8

Author(s):

Ming-Tao Zhao ◽

Ning-Yi Shao ◽

Shijun Hu ◽

Ning Ma ◽

Rajini Srinivasan ◽

...

Keyword(s):

Stem Cells ◽

Induced Pluripotent Stem Cells ◽

Pluripotent Stem Cells ◽

Somatic Cells ◽

Cell Type ◽

Dna Elements ◽

Cell Type Specific ◽

Induced Pluripotent ◽

Regulatory Dna

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Erratum: Donor cell type can influence the epigenome and differentiation potential of human induced pluripotent stem cells

Nature Biotechnology ◽

10.1038/nbt0112-112b ◽

2012 ◽

Vol 30 (1) ◽

pp. 112-112 ◽

Cited By ~ 2

Author(s):

Kitai Kim ◽

Rui Zhao ◽

Akiko Doi ◽

Kitwa Ng ◽

Juli Unternaehrer ◽

...

Keyword(s):

Stem Cells ◽

Induced Pluripotent Stem Cells ◽

Pluripotent Stem Cells ◽

Donor Cell ◽

Cell Type ◽

Differentiation Potential ◽

Induced Pluripotent ◽

Donor Cell Type

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Repair of Damaged Articular Cartilage: Current Approaches and Future Directions

International Journal of Molecular Sciences ◽

10.3390/ijms19082366 ◽

2018 ◽

Vol 19 (8) ◽

pp. 2366 ◽

Cited By ~ 55

Author(s):

Ekaterina Medvedeva ◽

Ekaterina Grebenik ◽

Svetlana Gornostaeva ◽

Vladimir Telpuhov ◽

Aleksey Lychagin ◽

...

Keyword(s):

Stem Cells ◽

Pluripotent Stem Cells ◽

Cell Expansion ◽

Hyaline Cartilage ◽

Self Renewal ◽

Future Directions ◽

Different Types ◽

Induced Pluripotent ◽

Low Cell Density

Articular hyaline cartilage is extensively hydrated, but it is neither innervated nor vascularized, and its low cell density allows only extremely limited self-renewal. Most clinical and research efforts currently focus on the restoration of cartilage damaged in connection with osteoarthritis or trauma. Here, we discuss current clinical approaches for repairing cartilage, as well as research approaches which are currently developing, and those under translation into clinical practice. We also describe potential future directions in this area, including tissue engineering based on scaffolding and/or stem cells as well as a combination of gene and cell therapy. Particular focus is placed on cell-based approaches and the potential of recently characterized chondro-progenitors; progress with induced pluripotent stem cells is also discussed. In this context, we also consider the ability of different types of stem cell to restore hyaline cartilage and the importance of mimicking the environment in vivo during cell expansion and differentiation into mature chondrocytes.

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Induced Pluripotent Stem Cells: Generation Strategy and Epigenetic Mystery behind Reprogramming

Stem Cells International ◽

10.1155/2016/8415010 ◽

2016 ◽

Vol 2016 ◽

pp. 1-11 ◽

Cited By ~ 5

Author(s):

Pengfei Ji ◽

Sasicha Manupipatpong ◽

Nina Xie ◽

Yujing Li

Keyword(s):

Stem Cells ◽

Induced Pluripotent Stem Cells ◽

Pluripotent Stem Cells ◽

Clinical Medicine ◽

Ethical Issues ◽

Somatic Cells ◽

Embryonic Stem ◽

Cell Types ◽

Self Renewal ◽

Induced Pluripotent

Possessing the ability of self-renewal with immortalization and potential for differentiation into different cell types, stem cells, particularly embryonic stem cells (ESC), have attracted significant attention since their discovery. As ESC research has played an essential role in developing our understanding of the mechanisms underlying reproduction, development, and cell (de)differentiation, significant efforts have been made in the biomedical study of ESC in recent decades. However, such studies of ESC have been hampered by the ethical issues and technological challenges surrounding them, therefore dramatically inhibiting the potential applications of ESC in basic biomedical studies and clinical medicine. Induced pluripotent stem cells (iPSCs), generated from the reprogrammed somatic cells, share similar characteristics including but not limited to the morphology and growth of ESC, self-renewal, and potential differentiation into various cell types. The discovery of the iPSC, unhindered by the aforementioned limitations of ESC, introduces a viable alternative to ESC. More importantly, the applications of iPSC in the development of disease models such as neurodegenerative disorders greatly enhance our understanding of the pathogenesis of such diseases and also facilitate the development of clinical therapeutic strategies using iPSC generated from patient somatic cells to avoid an immune rejection. In this review, we highlight the advances in iPSCs generation methods as well as the mechanisms behind their reprogramming. We also discuss future perspectives for the development of iPSC generation methods with higher efficiency and safety.

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Osteogenic potential of induced pluripotent stem cells from human adipose-derived stem cells

Stem Cell Research & Therapy ◽

10.1186/s13287-019-1402-y ◽

2019 ◽

Vol 10 (1) ◽

Cited By ~ 4

Author(s):

Shih-Hsuan Mao ◽

Chih-Hao Chen ◽

Chien-Tzung Chen

Keyword(s):

Stem Cells ◽

Induced Pluripotent Stem Cells ◽

Osteogenic Differentiation ◽

Nude Mice ◽

Pluripotent Stem Cells ◽

Adipose Derived Stem Cells ◽

Germ Layers ◽

Cell Source ◽

Induced Pluripotent

Abstract Background Bone regeneration is a crucial and challenging issue in clinical practice. Bone tissue engineering (BTE) with an optimal cell source may provide an ideal strategy for the reconstruction of bone defects. This study examined whether induced pluripotent stem cells (iPSCs) derived from adipose-derived stem cells (ASCs) could act as an osteogenic substitute and whether these ASC-iPSCs yield more new bone formation than ASCs in hydrogel scaffolds. Methods ASC-iPSCs were reprogrammed from ASCs through a retroviral system. ASCs were harvested and isolated from adipose tissue of humans. An aliquot of cell suspension (1 × 106 cells/mL) was seeded directly onto the nHAP-gelatin cryogel scaffolds. Nude mice back implantation of cell-seeded scaffolds was designed for in vivo comparison of osteogenic potentials between ASCs and ASC-iPSCs. Samples were harvested 4 and 8 weeks after implantation for further analysis based on histology and RT-PCR. Results ASC-iPSCs were successfully obtained from human adipose-derived stem cells. PCR results also showed that specific genes of iPSCs with the ability to cause the differentiation of cells into the three germ layers were expressed. In our in vivo experiments, iPSCs were subcutaneously injected into nude mice to induce teratoma formation. The morphology of the three germ layers was confirmed by histological staining. ASC is an essential cell source for BTE with benefits of high volume and less-invasive acquisition. With additional transforming Yamanaka factors, ASC-iPSCs showed higher osteogenic differentiation and elevated expression of collagen type I (Col I), osteocalcin (OCN), alkaline phosphate (ALP), and runt-related transcription factor 2 (RunX-2). Conclusions This report suggests that ASC-iPSCs could be a superior cell source in BTE with better osteogenic differentiation efficacy for future clinical applications.

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