Transdifferentiation Meets Next-generation Biotechnologies

Transdifferentiation is the process of converting terminally differentiated cells to another cell type. Being less time-consuming and free from tumorigenesis, it is a promising alternative to directed differentiation, which provides cell sources for tissue regeneration therapy and disease modeling. In the past decades, transdifferentiation was found to happen within or across the cell lineages, being induced by overexpression of key transcription factors, chemical cocktail treatments, etc. Implementing next-generation biotechnologies, such as genome editing tools and scRNA-seq, improves current protocols and has the potential to facilitate discovery in new pathways of transdifferentiation, which will accelerate its application in clinical use.

Prospects for Stem Cell-Based Regenerative Therapies in India

Stem cells offer a promising therapeutic strategy to not only treat several incurable diseases but also regenerate damaged tissues. The current global boom in the field of stem cell and regenerative therapies had led to India becoming a global hotspot for stem cell-based therapies. In this review, we assess the current status of stem cell therapy trials in India and show that the bone marrow-derived stem cells, like mesenchymal stem/stromal cells (MSCs), are predominantly used. Phase 1 and 2 clinical trials have also used MSCs to alleviate symptoms of severe novel coronavirus infections. Recent breakthroughs in gene editing technologies, combined with stem cell therapy, can be effectively harnessed to devise large-scale and affordable treatments for haematological diseases that are highly prevalent in India, like beta-thalassemia and sickle cell diseases. Innovations in stem cell therapy in India can make treatments more affordable to address the needs of in-country patients.

Human Pluripotent Stem Cell-Derived Organoids as a Model of Intestinal Xenobiotic Metabolism

Background: The human intestine is the site of absorption and first-pass metabolism for oral intake. Assessment of absorption, distribution, metabolism, excretion, and toxicity (ADMET) of xenobiotics has transformed the understanding of in vivo pharmacology. However, these processes are difficult torecapitulate in vitro. Objective: We have developed a simple protocol for the generation of mature functional intestinal organoids from human pluripotent stem cells (hPSCs)under xenogeneic-free conditions. We sought to characterize transcription level in drug transporters and metabolism and evaluate CYP3A4 catalytic function of the organoids. Methods: Human pluripotent stem cell-derived intestinal organoids were generated and evaluated the expression of drug transporters and metabolizing enzymes. We examined the induction of CYP3A4 and ABCB1 gene expression in the organoids. Furthermore, we analyzed the CYP3A4 enzyme activity of the organoids by the p450-Glo CYP3A4 assay kit with luciferin isopropyl acetal. Results: Stem cell-derived intestinal organoids had an outward polarized intestinal epithelial layer and showed similar expression levels of drug transporters and metabolism genes as the adult healthy intestine. They also exhibited CYP3A4 enzymatic function in vitro. Conclusion: This model provides a novel platform for pharmacological testing and can enhance human ADMET studies in drug development.

Organoid Maturation by Circadian Entrainment

Stem cell-derived tissues that recap endogenous physiology are key for regenerative medicine. Yet, most methods yield products that function like fetal, not adult tissues. Organoids are typically grown in constant environments, while our tissues mature along with behavioral cycles. Here, we show that inducing circadian rhythms in pancreatic islet organoids, by entraining them to daily feeding-fasting cycles, elicits their metabolic maturation. Our results show that rhythms can be harnessed to further functional maturation of organoids destined for human therapeutics.

More Bang for Your Buck: “Off-The-Shelf” Solutions for Cell Replacement Therapy

The immune barrier to transplantation has widely been recognized as the ultimate hurdle to the translation of stem cell-based therapies. In particular the polymorphic nature of the human leucocyte antigens (HLA) poses an imminent barrier to the successful engraftment of cells from other than autologous sources. To make stem cell therapies available to a larger pool of patients and a commercially viable option several groups have attempted to create hypoimmunogenic “universal” donor stem cells that evaded immune detection. The goal of this commentary is to give a brief overview of the current approaches taken and discuss challenges that need to be addressed to turn such cells into a viable commercial option.