Stem Cell Regenerative Medicine Research Articles

Comparison of the Characteristics of Breast Milk-derived Stem Cells with the Stem Cells Derived from the Other Sources: A Comparative Review

:Breast milk (BrM) is not only a nutrition supply but also contains a diverse population of cells. It has been estimated that up to 6% of the cells in human milk possess the characteristics of mesenchymal stem cells (MSC). Available data also indicate that these cells are multipotent and capable of self-renewal and differentiation to other cells. In this review, we have compared different characteristics such as CD markers, differentiation capacity, and morphology of stem cells derived from human breast milk (hBr-MSC) with human bone marrow (hBMSC), Wharton's jelly (WJMSC), and human adipose tissue (hADMSC). The literature review revealed that human breast milk-derived stem cells specifically express a group of cell surface markers, including CD14, CD31, CD45, and CD86. Importantly, a group of markers, CD13, CD29, CD44, CD105, CD106, CD146, and CD166, were identified which were common in the four sources of stem cells. WJMSC, hBMSC, hADMSC, and hBr-MSC are potently able to differentiate into the mesoderm, ectoderm, and endoderm cell lineages. The ability of hBr-MSCs in differentiation into the neural stem cells, neurons, adipocyte, hepatocyte, chondrocyte, osteocyte, and cardiomyocytes has made these cells a promising source of stem cells in regenerative medicine, while isolation of stem cells from the commonly used sources, such as bone marrow, requires invasive procedures. Although autologous breast milk-derived stem cells are an accessible source for women who are in the lactation period, breast milk can be considered a source of stem cells with high differentiation potential without any ethical concern.

Computational Methods to Identify Cell-Fate Determinants, Identity Transcription Factors, and Niche-Induced Signaling Pathways for Stem Cell Research.

The large-scale development of high-throughput sequencing technologies has not only allowed the generation of reliable omics data related to various regulatory layers but also the development of novel computational models in the field of stem cell research. These computational approaches have enabled the disentangling of a complex interplay between these interrelated layers of regulation by interpreting large quantities of biomedical data in a systematic way. In the context of stem cell research, network modeling of complex gene-gene interactions has been successfully used for understanding the mechanisms underlying stem cell differentiation and cellular conversion. Notably, it has proven helpful for predicting cell-fate determinants and signaling molecules controlling such processes. This chapter will provide an overview of various computational approaches that rely on single-cell and/or bulk RNA sequencing data for elucidating the molecular underpinnings of cell subpopulation identities, lineage specification, and the process of cell-fate decisions. Furthermore, we discuss how these computational methods provide the right framework for computational modeling of biological systems in order to address long-standing challenges in the stem cell field by guiding experimental efforts in stem cell research and regenerative medicine.

Application of mesenchymal stem cells derived from human pluripotent stem cells in regenerative medicine.

Mesenchymal stem cells (MSCs) represent the most clinically used stem cells in regenerative medicine. However, due to the disadvantages with primary MSCs, such as limited cell proliferative capacity and rarity in the tissues leading to limited MSCs, gradual loss of differentiation during in vitro expansion reducing the efficacy of MSC application, and variation among donors increasing the uncertainty of MSC efficacy, the clinical application of MSCs has been greatly hampered. MSCs derived from human pluripotent stem cells (hPSC-MSCs) can circumvent these problems associated with primary MSCs. Due to the infinite self-renewal of hPSCs and their differentiation potential towards MSCs, hPSC-MSCs are emerging as an attractive alternative for regenerative medicine. This review summarizes the progress on derivation of MSCs from human pluripotent stem cells, disease modelling and drug screening using hPSC-MSCs, and various applications of hPSC-MSCs in regenerative medicine. In the end, the challenges and concerns with hPSC-MSC applications are also discussed.

Single-Cell Sequencing to Unveil the Mystery of Embryonic Development.

Embryonic development is a fundamental physiological process that can provide tremendous insights into stem cell biology and regenerative medicine. In this process, cell fate decision is highly heterogeneous and dynamic, and investigations at the single-cell level can greatly facilitate the understanding of the molecular roadmap of embryonic development. Rapid advances in the technology of single-cell sequencing offer a perfectly useful tool to fulfill this purpose. Despite its great promise, single-cell sequencing is highly interdisciplinary, and successful applications in specific biological contexts require a general understanding of its diversity as well as the advantage versus limitations for each of its variants. Here, the technological principles of single-cell sequencing are consolidated and its applications in the study of embryonic development are summarized. First, the technology basics are presented and the available tools for each step including cell isolation, library construction, sequencing, and data analysis are discussed. Then, the works that employed single-cell sequencing are reviewed to investigate the specific processes of embryonic development, including preimplantation, peri-implantation, gastrulation, and organogenesis. Further, insights are provided on existing challenges and future research directions.

Biomolecular Electron Controller Composed of Nanobiohybrid with Electrically Released Complex for Spatiotemporal Control of Neuronal Differentiation.

In vitro spatiotemporal control of cell differentiation is a critical issue in several biomedical fields such as stem cell therapy and regenerative medicine, as it enables the generation of heterogeneous tissue structures similar to those of their native counterparts. However, the simultaneous control of both spatial and temporal cell differentiation poses important challenges, and therefore no previous studies have achieved this goal. Here, the authors develop a cell differentiation biomolecular electron controller ("Biomoletron") composed of recombinant proteins, DNA, Au nanoparticles, peptides, and an electrically released complex with retinoic acid (RA) to spatiotemporally control SH-SY5Y cell differentiation. RA is only released from the Biomoletron when the complex is electrically stimulated, thus demonstrating the temporal control of SH-SY5Y cell differentiation. Furthermore, by introducing a patterned Au substrate that allows controlling the area where the Biomoletron is immobilized, spatiotemporal differentiation of the SH-SY5Y cell is successfully achieved. Therefore, the proposed Biomoletron-mediated differentiation method provides a promising strategy for spatiotemporal cell differentiation control with applications in regenerative medicine and cell therapy.

Generation of Pericytic-Vascular Progenitors from Tankyrase/PARP-Inhibitor-Regulated Naïve (TIRN) Human Pluripotent Stem Cells.

Tankyrase/PARP inhibitor-regulated naïve human pluripotent stem cells (TIRN-hPSC) represent a new class of human stem cells for regenerative medicine that can differentiate into multi-lineage progenitors with improved in vivo functionality. Chemical reversion of conventional, primed hPSC to a TIRN-hPSC state alleviates dysfunctional epigenetic donor cell memory, lineage-primed gene expression, and potentially disease-associated aberrations in their differentiated progeny. Here, we provide methods for the reversion of normal or diseased patient-specific primed hPSC to TIRN-hPSC and describe their subsequent differentiation into embryonic-like pericytic-endothelial "naïve" vascular progenitors (N-VP). N-VP possess improved vascular functionality, high epigenetic plasticity, maintain greater genomic stability, and are more efficient in migrating to and re-vascularizing ischemic tissues than those generated from primed isogenic hPSC. We also describe detailed methods for the ocular transplantation and quantitation of vascular engraftment of N-VP into the ischemia-damaged neural retina of a humanized mouse model of ischemic retinopathy. The application of TIRN-hPSC-derived N-VP will advance vascular cell therapies of ischemic retinopathy, myocardial infarction, and cerebral vascular stroke.

Human platelet lysate (hPL) alters the lineage commitment and paracrine functions of human mesenchymal stem cells via mitochondrial metabolism

Emerging evidence indicates that cellular bioenergetics is critical in determining the self-renewal and differentiation of stem cells. Human platelet lysate (hPL) contains abundant proteins, which has been shown to improve self-renewal and osteogenic differentiation of mesenchymal stem cells (MSCs). However, the detailed modulating effect of hPL on MSCs energy metabolism remains unexplored. This study showed that MSCs cultured in hPL displayed a reduced cell size and cell spreading, but an improved proliferation and osteogenic capability compared with cells maintained in fetal bovine serum (FBS). RNA sequencing revealed widespread transcriptome differences between hPL- and FBS-MSCs where the differential expressed genes (DEGs) were enriched mainly in the PI3K-Akt and metabolic signal pathways. We found a significant downregulation of HIF1A (hypoxia-inducible factor 1 alpha) and altered mitochondrial features in hPL-MSCs, indicating a metabolism switch of the hPL-treated cells from glycolysis towards mitochondrial oxidative phosphorylation (OxPhos). It was also demonstrated that hPL-MSCs tend to differentiate towards the aerobic metabolism-demanded osteocytes or adipocytes rather than the anaerobic metabolism-demanded chondrocytes using a differentiation medium. Finally, hPL-MSCs showed an impaired paracrine function where the secreted factors cannot stimulate M2 polarization of THP1 cells and angiogenesis of HUVECs. We concluded that the PI3K-Akt/HIF1A-mediated metabolic state dominated the physiological property and lineage commitment of MSCs in hPL. For the first time, this study demonstrates the molecular mechanism of hPL in the regulation of metabolism and functions of MSCs, which implies the potential of hPL as an efficient biological material for stem cell engineering and regenerative medicine.

Single-Cell RNA Sequencing Analysis of Human Dental Pulp Stem Cell and Human Periodontal Ligament Stem Cell

IntroductionMany studies have investigated the transcriptome profiles of dental stem cells for regenerative medicine. However, such studies use bulk RNA and do not consider cell-level heterogeneity. Here, we investigated the characteristics and heterogeneity of human dental pulp stem cells (hDPSCs) and human periodontal ligament stem cells (hPDLSCs) at the single-cell level and examined the differences between them. MethodshDPSCs and hPDLSCs were obtained from caries-free premolars (n = 2). Single-cell RNA sequencing of hDPSCs and hPDLSCs was performed using a Single Emulsion Systems (Dolomite Microfluidics, Royston, UK) droplet microfluidic device and the Illumina NextSeq550 system (Illumina, San Diego, CA). Data alignment was performed using STAR v2.4.0, and further analysis was performed using the Seurat, singleR, and clusterProfiler packages in R (R Foundation for Statistical Computing, Vienna, Austria). ResultshDPSCs and hPDLSCs were separated into 3 clusters. hDPSCs mainly exhibited osteogenic and neurogenic cell populations. The main populations of hPDLSCs comprised osteogenic and myofibroblastic populations. hPDLSCs showed high “scores” for osteogenic gene expression, whereas hDPSCs had high neurogenic and endogenic scores. ConclusionsSingle-cell RNA sequencing of hDPSCs and hPDLSCs revealed that the genes were expressed in specific clusters. The results of these analyses can be used as reference databases and valuable resources for further research in dental therapeutics.

Abstract 13303: Identification of Critical Six Transcriptional Factors for Reprogramming of Mouse Adipose-Derived Regenerative Cells Toward Cardiomyocytes and Its Therapeutic Effect

Background: Adipose-derived regenerative cells (ADRCs) are promising stem cells for regenerative medicine that are easy to harvest from adipose tissues and can expand in vitro . While ADRCs can differentiate into mesodermal lineage cells including adipocytes, osteocytes, and chondrocytes, little is known about differentiating adult ADRCs into mature cardiomyocytes. Objective: The aim of this study was to explore how to differentiate adult mouse ADRCs into cardiomyocytes efficiently and test their effect on the myocardial infarction mouse model in vivo . Method and Results: We performed differential expression analysis to identify transcriptional factors which were upregulated in developing mice heart (E11.5) compared with ADRCs. We systemically screened the combinations of the required transcription factors in ADRCs derived from αMHC-EGFP reporter mice. Here, we identified the following six genes; Baf60c , Gata4 , Gata6 , Klf15 , Mef2a , Myocd , not more or less, as the best combination to efficiently induce αMHC in ADRCs. Fluorescence-activated cell sorting analysis showed that 3.0±0.61% (n=3) ADRCs were positive for αMHC after introducing these six factors. In addition, quantitative PCR demonstrated that several other marker genes of mature cardiomyocytes, including Actc1 , Tnnt2 , Ttn , Fhod3 , were confirmed to be upregulated by six factors. Immunocytochemical staining showed that most of the induced ADRCs had fibrous conformation of sarcomeric α-actin. Moreover, the gene expression pattern of the cells showed upregulation of genes associated with cardiac muscle cell differentiation. Finally, injection of the induced ADRCs into acute myocardial infarction lesions in vivo resulted in the improvement of survival rate (p=0.028, n=32), fractional shortening (p=0.012, n=7, 15), and the reduction of infarction scar area compared to the injection of ADRCs without induction (p=0.029, n=7). The induced ADRCs could survive in situ and continued to express the cardiac troponin T protein for four weeks after injection. Conclusions: The combination of six transcriptional factors could induce cardiomyocyte-like gene expression patterns on adult ADRCs. The induced ADRCs could have a therapeutic effect on an experimental ischemic heart model in vivo .

Industry Updates from the Field of Stem Cell Research and Regenerative Medicine in September 2021

Latest developments in the field of stem cell research and regenerative medicine compiled from publicly available information and press releases from nonacademic institutions in September 2021.

Pancreatic beta cell neogenesis: Debates and updates

Finding endogenous, renewable sources for insulin-producing beta cells in the adult pancreas is one of the holy grails of stem cell research and regenerative medicine. Through lineage tracing and scRNA-seq approaches, Gribben etal. (2021) have recently reported that Ngn3-expressing ductal cells could serve as progenitors for new beta cells in the adult pancreas.

Industry updates from the field of stem cell research and regenerative medicine in July 2021.

Latest developments in the field of stem cell research and regenerative medicine compiled from publicly available information and press releases from nonacademic institutions in July 2021.

Industry Updates From the Field of Stem Cell Research and Regenerative Medicine in August 2021

Latest developments in the field of stem cell research and regenerative medicine compiled from publicly available information and press releases from nonacademic institutions in August 2021.

Antiviral treatment causes a unique mutational signature in cancers of transplantation recipients

SummaryGenetic instability is a major concern for successful application of stem cells in regenerative medicine. However, the mutational consequences of the most applied stem cell therapy in humans, hematopoietic stem cell transplantation (HSCT), remain unknown. Here we characterized the mutation burden of hematopoietic stem and progenitor cells (HSPCs) of human HSCT recipients and their donors using whole-genome sequencing. We demonstrate that the majority of transplanted HSPCs did not display altered mutation accumulation. However, in some HSCT recipients, we identified multiple HSPCs with an increased mutation burden after transplantation. This increase could be attributed to a unique mutational signature caused by the antiviral drug ganciclovir. Using a machine learning approach, we detected this signature in cancer genomes of individuals who received HSCT or solid organ transplantation earlier in life. Antiviral treatment with nucleoside analogs can cause enhanced mutagenicity in transplant recipients, which may ultimately contribute to therapy-related carcinogenesis.

Generation of a control human induced pluripotent stem cell line using the defective and persistent Sendai virus vector system

The defective and persistent Sendai virus (SeVdp) vector system allows efficient generation of transgene-free induced pluripotent stem cells (iPSCs) from human somatic cells. By leveraging the system, here we report the generation of an iPSC line from somatic fibroblasts of a healthy control donner (female), named KEIOi002-A (also named YG-iPS). The control iPSC line would be a useful resource for stem cell research and regenerative medicine.

An overview of mesenchymal stem cells and their potential therapeutic benefits in cancer therapy (Review)

There has been increased interest in using stem cells for regenerative medicine and cancer therapy in the past decade. Mesenchymal stem cells (MSCs) are among the most studied stem cells due to their unique characteristics, such as self-renewal and developmental potency to differentiate into numerous cell types. MSC use has fewer ethical challenges compared with other types of stem cells. Although a number of studies have reported the beneficial effects of MSC-based therapies in treating various diseases, their contribution to cancer therapy remains controversial. The behaviour of MSCs is determined by the interaction between intrinsic transcriptional genes and extrinsic environmental factors. Numerous studies continue to emerge, as there is no denying the potential of MSCs to treat a wide variety of human afflictions. Therefore, the present review article provided an overview of MSCs and their differences compared with embryonic stem cells, and described the molecular mechanisms involved in maintaining their stemness. In addition, the article examined the therapeutic application of stem cells in the field of cancer. The present article also discussed the current divergent roles of MSCs in cancer therapy and the future potential in this field.

An In Vitro and In Vivo Comparison of Osteogenic Differentiation of Human Mesenchymal Stromal/Stem Cells.

The use of stem cells in regenerative medicine, including tissue engineering and transplantation, has generated a great deal of enthusiasm. Mesenchymal stromal/stem cells (MSCs) can be isolated from various tissues, most commonly, bone marrow but more recently adipose tissue, dental pulp, and Wharton's jelly, to name a few. MSCs display varying phenotypic profiles and osteogenic differentiating capacity depending and their site of origin. MSCs have been successfully differentiated into osteoblasts both in vitro an in vivo but discrepancies exist when the two are compared: what happens in vitro does not necessarily happen in vivo, and it is therefore important to understand why these differences occur. The osteogenic process is a complex network of transcription factors, stimulators, inhibitors, proteins, etc., and in vivo experiments are helpful in evaluating the various aspects of this osteogenic process without distractions and confounding variables. With that in mind, the results of in vitro experiments need to be carefully considered and interpreted with caution as they do not perfectly replicate the conditions found within living organisms. This is where in vivo experiments help us better understand interactions that might occur in the osteogenic process that cannot be replicated in vitro. Potentially, these differences could also be exploited to develop an optimal MSC cell therapeutic product that can be used for bone disorders. There are many bone disorders, most of which cause a great deal of discomfort. Clinically acceptable protocols could be developed in which MSCs are used to aid in bone regeneration providing relief for patients with chronic pain. The aim of this review is to examine the differences between studies conducted in vitro and in vivo with regard to the osteogenic process to better define the gaps in current osteogenic research. By better understanding osteogenic differentiation, we can better define treatment strategies for various bone disorders.

Intra-Arterial Delivery of Mesenchymal Stem Cells for Regenerative Medicine to Treat Peripheral Arterial Disease

Despite therapeutic advances, peripheral arterial disease (PAD) is a rapidly progressing disease, which often Results in critical limb ischemia requiring amputation. Several in vivo studies have shown that perivascular inflammation and intima dysfunction due to PAD might contribute to the development of neointimal hyperplasia. As such, a need exists for new technology to enhance conventional treatments by directly targeting the adventitia. Through the use of porcine models, this study explored intra-arterial delivery of mesenchymal stem cells (MSCs) as a method of targeting and potentially treating arterial walls.

Biomaterials and Adipose-Derived Mesenchymal Stem Cells for Regenerative Medicine: A Systematic Review.

The use of biological templates for the suitable growth of adipose-derived mesenchymal stem cells (AD-MSC) and “neo-tissue” construction has exponentially increased over the last years. The bioengineered scaffolds still have a prominent and biocompatible framework playing a role in tissue regeneration. In order to supply AD-MSCs, biomaterials, as the stem cell niche, are more often supplemented by or stimulate molecular signals that allow differentiation events into several strains, besides their secretion of cytokines and effects of immunomodulation. This systematic review aims to highlight the details of the integration of several types of biomaterials used in association with AD-MSCs, collecting notorious and basic data of in vitro and in vivo assays, taking into account the relevance of the interference of the cell lineage origin and handling cell line protocols for both the replacement and repairing of damaged tissues or organs in clinical application. Our group analyzed the quality and results of the 98 articles selected from PubMed, Scopus and Web of Science. A total of 97% of the articles retrieved demonstrated the potential in clinical applications. The synthetic polymers were the most used biomaterials associated with AD-MSCs and almost half of the selected articles were applied on bone regeneration.

Industry updates from the field of stem cell research and regenerative medicine in June 2021.

The latest developments in the field of stem cell research and regenerative medicine compiled from publicly available information and press releases from nonacademic institutions in June 2021.