Liver transplantation is the only curative option for many liver diseases that end up in liver failure, and cholangiopathy remains a challenging complication post-liver transplant, associated with significant morbidity and potential graft loss. The low availability of organs and high demand for transplantation motivate scientists to find novel interventions. Organoids, as three-dimensional cell cultures derived from adult cells or induced pluripotent cells, may help to address this problem. Different types of organoids have been described, from which cholangiocyte organoids offer a high level of versatility and plasticity for a deeper study of liver disease mechanisms. Cholangiocytes can be obtained from different segments of the biliary tree and have shown a remarkable capacity to adapt to new environments, presenting an effective system for studying cholangiopathies. Studies using cholangiocyte organoids show promising results for disease modeling, where organoids offer fundamental features to recapitulate the complexities of tissues in vitro and uncover fundamental pathological pathways to potentially reveal therapeutic strategies for personalized medicine. Organoids could hold the potential for regeneration of injured livers, representing tools of clinical impact in regenerative medicine when tissue damage is already present.

Pigs (Sus scrofa) are widely acknowledged as an important large mammalian animal model due to their similarity to human physiology, genetics, and immunology. Leveraging the full potential of this model presents significant opportunities for major advancements in the fields of comparative biology, disease modeling, and regenerative medicine. Thus, the derivation of pluripotent stem cells from this species can offer new tools for disease modeling and serve as a stepping stone to test future autologous or allogeneic cell-based therapies. Over the past few decades, great progress has been made in establishing porcine pluripotent stem cells (pPSCs), including embryonic stem cells (pESCs) derived from pre- and peri-implantation embryos, and porcine induced pluripotent stem cells (piPSCs) using a variety of cellular reprogramming strategies. However, the stabilization of pPSCs was not as straightforward as directly applying the culture conditions developed and optimized for murine or primate PSCs. Therefore, it has historically been challenging to establish stable pPSC lines that could pass stringent pluripotency tests. Here, we review recent advances in the establishment of stable porcine PSCs. We focus on the evolving derivation methods that eventually led to the establishment of pESCs and transgene-free piPSCs, as well as current challenges and opportunities in this rapidly advancing field.

Cartilage, an important connective tissue, provides structural support to other body tissues, and serves as a cushion against impacts throughout the body. Found at the end of the bones, cartilage decreases friction and averts bone-on-bone contact during joint movement. Therefore, defects of cartilage can result from natural wear and tear, or from traumatic events, such as injuries or sudden changes in direction during sports activities. Overtime, these cartilage defects which do not always produce immediate symptoms, could lead to severe clinical pathologies. The emergence of induced pluripotent stem cells (iPSCs) has revolutionized the field of regenerative medicine, providing a promising platform for generating various cell types for therapeutic applications. Thus, chondrocytes differentiated from iPSCs become a promising avenue for non-invasive clinical interventions for cartilage injuries and diseases. In this review, we aim to highlight the current strategies used for in vitro chondrogenic differentiation of iPSCs and to explore their multifaceted applications in disease modeling, drug screening, and personalized regenerative medicine. Achieving abundant functional iPSC-derived chondrocytes requires optimization of culture conditions, incorporating specific growth factors, and precise temporal control. Continual improvements in differentiation methods and integration of emerging genome editing, organoids, and 3D bioprinting technologies will enhance the translational applications of iPSC-derived chondrocytes. Finally, to unlock the benefits for patients suffering from cartilage diseases through iPSCs-derived technologies in chondrogenesis, automatic cell therapy manufacturing systems will not only reduce human intervention and ensure sterile processes within isolator-like platforms to minimize contamination risks, but also provide customized production processes with enhanced scalability and efficiency.

Brain organoid is a three-dimensional (3D) tissue derived from stem cells such as induced pluripotent stem cells (iPSCs) embryonic stem cells (ESCs) that reflect real human brain structure. It replicates the complexity and development of the human brain, enabling studies of the human brain in vitro. With emerging technologies, its application is various, including disease modeling and drug screening. A variety of experimental methods have been used to study structural and molecular characteristics of brain organoids. However, electrophysiological analysis is necessary to understand their functional characteristics and complexity. Although electrophysiological approaches have rapidly advanced for monolayered cells, there are some limitations in studying electrophysiological and neural network characteristics due to the lack of 3D characteristics. Herein, electrophysiological measurement and analytical methods related to neural complexity and 3D characteristics of brain organoids are reviewed. Overall, electrophysiological understanding of brain organoids allows us to overcome limitations of monolayer in vitro cell culture models, providing deep insights into the neural network complex of the real human brain and new ways of disease modeling. [BMB Reports 2024; 57(7): 311-317].

Spinocerebellar ataxias (SCAs) are a rare autosomal dominant neurodegenerative disorder. To date, approximately 50 different subtypes of SCAs have been characterized. The prevalent types of SCAs are usually of PolyQ origin, wherein the disease pathology is a consequence of multiple glutamine residues being encoded onto the disease proteins, causing expansions. SCAs 2 and 3 are the most frequently diagnosed subtypes, wherein affected patients exhibit certain characteristic physiological manifestations, such as gait ataxia and dysarthria. Nevertheless, other clinical signs were exclusive to these subtypes. Recently, multiple molecular diagnostic methods have been developed to identify and characterize these subtypes. Despite these advancements, the molecular pathology of SCAs remains unknown. To further understand the mechanisms involved in neurodegenerative SCAs 2 and 3, patient-derived induced pluripotent stem cell (iPSC)-based modelling is a compelling avenue to pursue. We cover the present state of iPSC-based in-vitro illness modelling of SCA subtypes 2 and 3 below, along with a list of cell lines created, and the relevance of research outcomes to personalized autologous therapy.

In exploring therapeutic options for ischemic heart disease (IHD) and heart failure, cell-based cardiac repair has gained prominence. This systematic review delves into the current state of knowledge surrounding cell-based therapies for cardiac repair. Employing a comprehensive search across relevant databases, the study identifies 35 included studies with diverse cell types and methodologies. Encouragingly, these findings reveal the promise of cell-based therapies in cardiac repair, demonstrating significant enhancements in left ventricular ejection fraction (LVEF) across the studies. Mechanisms of action involve growth factors that stimulate angiogenesis, differentiation, and the survival of transplanted cells. Despite these positive outcomes, challenges persist, including low engraftment rates, limitations in cell differentiation, and variations in clinical reproducibility. The optimal dosage and frequency of cell administration remain subjects of debate, with potential benefits from repeated dosing. Additionally, the choice between autologous and allogeneic stem cell transplantation poses a critical decision. This systematic review underscores the potential of cell-based therapies for cardiac repair, bearing implications for innovative treatments in heart diseases. However, further research is imperative to optimize cell type selection, delivery techniques, and long-term efficacy, fostering a more comprehensive understanding of cell-based cardiac repair.

Local anesthetic (LA) cardiotoxicity is one of the main health problems in anesthesiology and pain management. This study reviewed the reported LA-induced cardiac toxicity types, risk factors, management, and mechanisms, with attention to the use of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) in heart toxicity research. Important scientific databases were searched to find relevant articles. We briefly assessed the reported cardiotoxic effects of different types of LA drugs, including ester- and amide-linked LA agents. Furthermore, cardiotoxic effects and clinical manifestations, strategies for preventing and managing LA-induced cardiotoxic effects, pharmacokinetics, pharmacodynamics, and sodium channel dynamics regarding individual variability and genetic influences were discussed in this review. The applications and importance of hiPSC-CMs cellular model for evaluating the cardiotoxic effects of LA drugs were discussed in detail. This review also explored hiPSC-CMs\' potential in risk assessment, drug screening, and developing targeted therapies. The main mechanisms underlying LA-induced cardiotoxicity included perturbation in sodium channels, ROS production, and disorders in the immune system response due to the presence of LA drugs. Furthermore, drug-specific characteristics including pharmacokinetics and pharmacodynamics are important determinants after LA drug injection. In addition, individual patient factors such as age, comorbidities, and genetic variability emphasize the need for a personalized approach to mitigate risks and enhance patient safety. The strategies outlined for the prevention and management of LA cardiotoxicity underscore the importance of careful dosing, continuous monitoring, and the immediate availability of resuscitation equipment. This comprehensive review can be used to guide future investigations into better understanding LA cardiac toxicities and improving patient safety.

With the use of specific genetic factors and recent developments in cellular reprogramming, it is now possible to generate lineage-committed cells or induced pluripotent stem cells (iPSCs) from readily available and common somatic cell types. However, there are still significant doubts regarding the safety and effectiveness of the current genetic methods for reprogramming cells, as well as the conventional culture methods for maintaining stem cells. Small molecules that target specific epigenetic processes, signaling pathways, and other cellular processes can be used as a complementary approach to manipulate cell fate to achieve a desired objective. It has been discovered that a growing number of small molecules can support lineage differentiation, maintain stem cell self-renewal potential, and facilitate reprogramming by either increasing the efficiency of reprogramming or acting as a genetic reprogramming factor substitute. However, ongoing challenges include improving reprogramming efficiency, ensuring the safety of small molecules, and addressing issues with incomplete epigenetic resetting. Small molecule iPSCs have significant clinical applications in regenerative medicine and personalized therapies. This review emphasizes the versatility and potential safety benefits of small molecules in overcoming challenges associated with the iPSCs reprogramming process.

BACKGROUND: Stem cell research, particularly in the domain of induced pluripotent stem cell (iPSC) technology, has shown significant progress. The integration of artificial intelligence (AI), especially machine learning (ML) and deep learning (DL), has played a pivotal role in refining iPSC classification, monitoring cell functionality, and conducting genetic analysis. These enhancements are broadening the applications of iPSC technology in disease modelling, drug screening, and regenerative medicine. This review aims to explore the role of AI in the advancement of iPSC research.
METHODS: In December 2023, data were collected from three electronic databases (PubMed, Web of Science, and Science Direct) to investigate the application of AI technology in iPSC processing.
RESULTS: This systematic scoping review encompassed 79 studies that met the inclusion criteria. The number of research studies in this area has increased over time, with the United States emerging as a leading contributor in this field. AI technologies have been diversely applied in iPSC technology, encompassing the classification of cell types, assessment of disease-specific phenotypes in iPSC-derived cells, and the facilitation of drug screening using iPSC. The precision of AI methodologies has improved significantly in recent years, creating a foundation for future advancements in iPSC-based technologies.
CONCLUSIONS: Our review offers insights into the role of AI in regenerative and personalized medicine, highlighting both challenges and opportunities. Although still in its early stages, AI technologies show significant promise in advancing our understanding of disease progression and development, paving the way for future clinical applications.

Stem cells are ubiquitously found in various tissues and organs in the body, and underpin the body\'s ability to repair itself following injury or disease initiation, though repair can sometimes be compromised. Understanding how stem cells are produced, and functional signaling systems between different niches is critical to understanding the potential use of stem cells in regenerative medicine. In this context, this review considers kynurenine pathway (KP) metabolism in multipotent adult progenitor cells, embryonic, haematopoietic, neural, cancer, cardiac and induced pluripotent stem cells, endothelial progenitor cells, and mesenchymal stromal cells. The KP is the major enzymatic pathway for sequentially catabolising the essential amino acid tryptophan (TRP), resulting in key metabolites including kynurenine, kynurenic acid, and quinolinic acid (QUIN). QUIN metabolism transitions into the adjoining de novo pathway for nicotinamide adenine dinucleotide (NAD) production, a critical cofactor in many fundamental cellular biochemical pathways. How stem cells uptake and utilise TRP varies between different species and stem cell types, because of their expression of transporters and responses to inflammatory cytokines. Several KP metabolites are physiologically active, with either beneficial or detrimental outcomes, and evidence of this is presented relating to several stem cell types, which is important as they may exert a significant impact on surrounding differentiated cells, particularly if they metabolise or secrete metabolites differently. Interferon-gamma (IFN-γ) in mesenchymal stromal cells, for instance, highly upregulates rate-limiting enzyme indoleamine-2,3-dioxygenase (IDO-1), initiating TRP depletion and production of metabolites including kynurenine/kynurenic acid, known agonists of the Aryl hydrocarbon receptor (AhR) transcription factor. AhR transcriptionally regulates an immunosuppressive phenotype, making them attractive for regenerative therapy. We also draw attention to important gaps in knowledge for future studies, which will underpin future application for stem cell-based cellular therapies or optimising drugs which can modulate the KP in innate stem cell populations, for disease treatment.