Menstrual blood stem cells as a potential source for cell therapy

Cell replacement and restorative therapies show great promise for the treatment of various diseases and traumas. Various types of stem cells that are rather different in terms of biological properties are evaluated as potential sources for cell therapy. Mesenchymal stem cells (MSCs) display relatively high proliferative activity and high level of plasticity and can be differentiated not only into cells of mesenchymal lineage, but also neurons. Among the MSC populations, the population of endometrial stem cells, including that present in the menstrual blood, is readily available. In the current review, we analyze the biological properties of the menstrual blood stem cells and the possibilities of using them as a potential source for cell therapy.     

Prospects for pluripotent stem cell‐derived cardiomyocytes in cardiac cell therapy and as disease models

The derivation of embryonic stem cells (hESC) from human embryos a decade ago started a new era in perspectives for cell therapy as well as understanding human development and disease. More recently, reprogramming of somatic cells to an embryonic stem cell‐like state (induced pluripotent stem cells, iPS) presented a new milestone in this area, making it possible to derive all cells types from any patients bearing specific genetic mutations. With the development of efficient differentiation protocols we are now able to use the derivatives of pluripotent stem cells to study mechanisms of disease and as human models for drug and toxicology testing. In addition derivatives of pluripotent stem cells are now close to be used in clinical practice although for the heart, specific additional challenges have been identified that preclude short‐term application in cell therapy. Here we review techniques presently used to induce differentiation of pluripotent stem cells into cardiomyocytes and the potential these cells have as disease models and for therapy. J. Cell. Biochem. 107: 592–599, 2009. © 2009 Wiley‐Liss, Inc.     

Induced pluripotent stem cells derived from human amnion in chemically defined conditions

Fetal stem cells are a unique type of adult stem cells that have been suggested to be broadly multipotent with some features of pluripotency. Their clinical potential has been documented but their upgrade to full pluripotency could open up a wide range of cell-based therapies particularly suited for pediatric tissue engineering, longitudinal studies or disease modeling. Here we describe episomal reprogramming of mesenchymal stem cells from the human amnion to pluripotency (AM-iPSC) in chemically defined conditions. The AM-iPSC expressed markers of embryonic stem cells, readily formed teratomas with tissues of all three germ layers present and had a normal karyotype after around 40 passages in culture. We employed novel computational methods to determine the degree of pluripotency from microarray and RNA sequencing data in these novel lines alongside an iPSC and ESC control and found that all lines were deemed pluripotent, however, with variable scores. Differential expression analysis then identified several groups of genes that potentially regulate this variability in lines within the boundaries of pluripotency, including metallothionein proteins. By further studying this variability, characteristics relevant to cell-based therapies, like differentiation propensity, could be uncovered and predicted in the pluripotent stage.     

Human amnion-derived mesenchymal stem cells are a potential source for uterine stem cell therapy

Abstract. Objectives: Human amnion is an easy‐to‐obtain novel source of human mesenchymal stem cells, which poses little or no ethical dilemmas. We have previously shown that human amnion‐derived mesenchymal (HAM) cells exhibit certain mesenchymal stem cell‐like characteristics with respect to expression of stem cell markers and differentiation potentials. Materials and methods: In this study, we further characterized HAM cells’ potential for in vivo therapeutic application. Results: Flow cytometric analyses of HAM cells show that they express several stem cell‐related cell surface markers, including CD90, CD105, CD59, CD49d, CD44 and HLA‐ABC, but not CD45, CD34, CD31, CD106 or HLA‐DR. HAM cells at the 10th passage showed normal karyotype. More interestingly, the AbdB‐like HOXA genes HOXA9, HOXA10 and HOXA11 that are expressed in the mesenchyme of the developing female reproductive tract and pregnant uteri are also expressed in HAM cells, suggesting similarities between these two mesenchymal cell types. Progesterone receptor is also highly expressed in HAM cells and expression of genes or proteins in HAM cells could be manipulated with the aid of lentivirus technology or cell‐permeable peptides. To test potentials of HAM cells for in vivo application, we introduced enhanced green fluorescence protein (EGFP)‐expressing HAM cells to mice by intrauterine infusion (into uteri) or by intravenous injection (into the circulation). Presence of EGFP‐expressing cells within the uterine mesenchyme after intrauterine infusion or in lungs after intravenous injection was noted within 1–4 weeks. Conclusions: Collectively, these results suggest that HAM cells are a potential source of mesenchymal stem cells with therapeutic potential.     

Liver engraftment potential of hepatic cells derived from patient-specific induced pluripotent stem cells

Human induced pluripotent stem cells (iPSCs) are potential renewable sources of hepatocytes for drug development and cell therapy. Differentiation of human iPSCs into different developmental stages of hepatic cells has been achieved and improved during the last several years. We have recently demonstrated the liver engraftment and regenerative capabilities of human iPSC-derived multistage hepatic cells in vivo. Here we describe the in vitro and in vivo activities of hepatic cells derived from patientspecific iPSCs, including multiple lines established from either inherited or acquired liver diseases, and discuss basic and clinical applications of these cells for disease modeling, drug screening and discovery, gene therapy and cell replacement therapy.Key words: induced pluripotent stem cells (iPSCs), hepatic differentiation, liver ngraftment, disease modeling, drug testing, alpha-1 antitrypsin, liver cirrhosis, hepatocellular carcinoma, cell therapy     

Liver engraftment potential of hepatic cells derived from patient-specific induced pluripotent stem cells

Human induced pluripotent stem cells (iPSCs) are potential renewable sources of hepatocytes for drug development and cell therapy. Differentiation of human iPSCs into different developmental stages of hepatic cells has been achieved and improved during the last several years. We have recently demonstrated the liver engraftment and regenerative capabilities of human iPSC-derived multistage hepatic cells in vivo. Here we describe the in vitro and in vivo activities of hepatic cells derived from patient specific iPSCs, including multiple lines established from either inherited or acquired liver diseases, and discuss basic and clinical applications of these cells for disease modeling, drug screening and discovery, gene therapy and cell replacement therapy.     

Induced pluripotent stem cells from hair follicles as a cellular model for neurodevelopmental disorders

Disease-specific induced pluripotent stem cells (iPSC) allow unprecedented experimental platforms for basic research as well as high-throughput screening. This may be particularly relevant for neuropsychiatric disorders, in which the affected neuronal cells are not accessible. Keratinocytes isolated from hair follicles are an ideal source of patients' cells for reprogramming, due to their non-invasive accessibility and their common neuroectodermal origin with neurons, which can be important for potential epigenetic memory. From a small number of plucked human hair follicles obtained from two healthy donors we reprogrammed keratinocytes to pluripotent iPSC. We further differentiated these hair follicle-derived iPSC to neural progenitors, forebrain neurons and functional dopaminergic neurons.This study shows that human hair follicle-derived iPSC can be differentiated into various neural lineages, suggesting this experimental system as a promising in vitro model to study normal and pathological neural developments, avoiding the invasiveness of commonly used skin biopsies.     

Human induced pluripotent stem cells derived hepatocytes: rising promise for disease modeling,drug development and cell therapy

Recent advances in the study of human hepatocytes derived from induced pluripotent stem cells (iPSC) represent new promises for liver disease study and drug discovery. Human hepatocytes or hepatocyte-like cells differentiated from iPSC recapitulate many functional properties of primary human hepatocytes and have been demonstrated as a powerful and efficient tool to model human liver metabolic diseases and facilitate drug development process. In this review, we summarize the recent progress in this field and discuss the future perspective of the application of human iPSC derived hepatocytes.     

Induced pluripotent stem cells from patients with Huntington's disease show CAG-repeat-expansion-associated phenotypes

Huntington's disease (HD) is an inherited neurodegenerative disorder caused by an expanded stretch of CAG trinucleotide repeats that results in neuronal dysfunction and death. Here, The HD Consortium reports the generation and characterization of 14 induced pluripotent stem cell (iPSC) lines from HD patients and controls. Microarray profiling revealed CAG-repeat-expansion-associated gene expression patterns that distinguish patient lines from controls, and early onset versus late onset HD. Differentiated HD neural cells showed disease-associated changes in electrophysiology, metabolism, cell adhesion, and ultimately cell death for lines with both medium and longer CAG repeat expansions. The longer repeat lines were however the most vulnerable to cellular stressors and BDNF withdrawal, as assessed using a range of assays across consortium laboratories. The HD iPSC collection represents a unique and well-characterized resource to elucidate disease mechanisms in HD and provides a human stem cell platform for screening new candidate therapeutics.     

Prospects and challenges of induced pluripotent stem cells as a source of hematopoietic stem cells

Many life-threatening hematological diseases are now treated by bone marrow transplantations, i.e., infusion of hematopoietic stem cells (HSCs). HSC transplantations are a valid option for the treatment of a variety of metabolic disorders, and even for solid tumors and some refractory severe autoimmune diseases. Unfortunately, the frequency and outcome of HSC transplantations are limited by a shortage of suitable donors. Induced pluripotent stem cells (iPSCs)-somatic cells that have acquired pluripotent stem cell characteristics by the ectopic expression of pluripotency-inducing factors-have been proposed as an alternative source of HSCs. Possible applications include cells of autologous, of autologous and genetically modified, or of allogeneic origin. Here, we provide a perspective on the distinct opportunities of iPSCs and discuss the challenges that lie ahead.     

Induced pluripotent stem cell-based disease modeling and prospective immune therapy for coronavirus disease 2019

The emergence of the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic poses a never before seen challenge to human health and the economy. Considering its clinical impact, with no streamlined therapeutic strategies in sight, it is crucial to understand the infection process of SARS-CoV-2. Our limited knowledge of the mechanisms underlying SARS-CoV-2 infection impedes the development of alternative therapeutics to address the pandemic. This aspect can be addressed by modeling SARS-CoV-2 infection in the human context to facilitate drug screening and discovery. Human induced pluripotent stem cell (iPSC)-derived lung epithelial cells and organoids recapitulating the features and functionality of the alveolar cell types can serve as an in vitro human model and screening platform for SARS-CoV-2. Recent studies suggest an immune system asynchrony leading to compromised function and a decreased proportion of specific immune cell types in coronavirus disease 2019 (COVID-19) patients. Replenishing these specific immune cells may serve as useful treatment modality against SARS-CoV-2 infection. Here the authors review protocols for deriving lung epithelial cells, alveolar organoids and specific immune cell types, such as T lymphocytes and natural killer cells, from iPSCs with the aim to aid investigators in making relevant in vitro models of SARS-CoV-2 along with the possibility derive immune cell types to treat COVID-19.     

Characterization of a pluripotent stem cell line derived from a mouse embryo

A pluripotent, karyotypically normal, male culture line ESC-BLC 1 of embryonal stem cells was established from delayed mouse blastocysts of strain 129/ter Sv. The cell line was isolated after cultivation of inner cell mass cells on X-irradiated feeder layer of mouse embryonal fibroblasts. The pluripotent status of the cell line was confirmed by in vivo and in vitro differentiation. For in vivo differentiation, cells were injected subcutaneously into syngeneic mice. The resulting tumors contained various tissues, derivatives of all three primary germ layers. In vitro cultivated pluripotent stem cells differentiated into endoderm-like, neuronal-like and tubular structures. Determination of alkaline phosphatase in cell line ESC-BLC 1 yielded a high specific activity; G-banding of metaphases revealed a normal, male karyotype.     

Induced pluripotent stem cells as a tool for gaining new insights into Fanconi anemia

Induced pluripotent stem cells (iPSC) hold significant promise for advancing biomedical research. In the case of monogenic diseases, patient-iPSC and their derivatives contain the disease-causing mutation, suggesting the possibility of recapitulating salient disease features in vitro. Fanconi anemia (FA) is the most common inherited bone marrow failure syndrome. The etiology of bone marrow failure in FA remains largely unclear, but limited studies on patient bone marrow cells indicate cell intrinsic defects as causative. We examined the feasibility of modeling FA in a system based on hematopoietic differentiation of patient-specific iPSC. An informative iPSC-based model is predicated on the ability to derive disease-specific (uncorrected) patient iPSC that contain the disease-causing mutation, are pluripotent, maintain a normal karyotype and are capable of hematopoietic differentiation. Careful analysis of hematopoietic differentiation of such iPSC holds the promise of uncovering new insights into bone marrow failure and may enable high-throughput screening with the goal of identifying compounds that ameliorate hematopoietic failure. Ultimately, genetic correction, molecular characterization and successful engraftment of iPSC-derived cells may provide an attractive alternative to current hematopoietic stem cell-targeted gene therapy in some monogenic diseases, including FA.