Clinical applications of pluripotent stem cells and their derivatives: current status and future perspectives

Research progress of neural stem cells as a source of dopaminergic neurons for cell therapy in Parkinson's disease

Parkinson's disease (PD) is a neurodegenerative disease, the most characteristic pathological feature is the progressive loss of dopaminergic (DA) neurons in the substantia nigra pars compactus (SNpc) of the mesencephalon, along with reduced dopamine content in the striatum. Researchers have been searching for drugs and therapies to treat PD in decades. However, no approach could stop the progression of the disease, and even some of them caused adverse clinical side effects. PD has a well-defined lesion. Therefore, it is considered to be one of the most curable central nervous system diseases by cell replacement treatment. Fetal ventral mesencephalic tissue transplantation has been used to treat patients with PD and obtained positive treatment results. However, ethical issues, such as limited donor tissue, and side effects including graft-induced dyskinesias, limit its clinical applications. Neural stem cell (NSC) transplantation is a viable therapy choice because it possesses multipotency, self-renewal ability, and differentiation into DA neurons, which may substitute for lost DA neurons and slow down the neurodegenerative process in PD. Studies that investigated the delivery of NSCs by using animal models of PD revealed survival, migration, and even amelioration of behavioral deficits. Here, the research progress of NSCs or NSC-derived DA neurons in treating PD was reviewed, and the practicability of present manufacturing processes for clinical testing was considered. This review is expected to offer ideas for practical strategies to solve the present technical and biological problems related to the clinical application of NSCs in PD.

Epigenetic regulation and factors that influence the effect of iPSCs-derived neural stem/progenitor cells (NS/PCs) in the treatment of spinal cord injury

Spinal cord injury (SCI) is a severe neurological disorder that causes neurological impairment and disability. Neural stem/progenitor cells (NS/PCs) derived from induced pluripotent stem cells (iPSCs) represent a promising cell therapy strategy for spinal cord regeneration and repair. However, iPSC-derived NS/PCs face many challenges and issues in SCI therapy; one of the most significant challenges is epigenetic regulation and that factors that influence this mechanism. Epigenetics refers to the regulation of gene expression and function by DNA methylation, histone modification, and chromatin structure without changing the DNA sequence. Previous research has shown that epigenetics plays a crucial role in the generation, differentiation, and transplantation of iPSCs, and can influence the quality, safety, and outcome of transplanted cells. In this study, we review the effects of epigenetic regulation and various influencing factors on the role of iPSC-derived NS/PCs in SCI therapy at multiple levels, including epigenetic reprogramming, regulation, and the adaptation of iPSCs during generation, differentiation, and transplantation, as well as the impact of other therapeutic tools (e.g., drugs, electrical stimulation, and scaffolds) on the epigenetic status of transplanted cells. We summarize our main findings and insights in this field and identify future challenges and directions that need to be addressed and explored.

Autologous Stem Cell Transplant in Hodgkin's and Non-Hodgkin's Lymphoma, Multiple Myeloma, and AL Amyloidosis

Human body cells are stem cell (SC) derivatives originating from bone marrow. Their special characteristics include their capacity to support the formation and self-repair of the cells. Cancer cells multiply uncontrollably and invade healthy tissues, making stem cell transplants a viable option for cancer patients undergoing high-dose chemotherapy (HDC). When chemotherapy is used at very high doses to eradicate all cancer cells from aggressive tumors, blood-forming cells and leukocytes are either completely or partially destroyed. Autologous stem cell transplantation (ASCT) is necessary for patients in those circumstances. The patients who undergo autologous transplants receive their own stem cells (SCs). The transplanted stem cells first come into contact with the bone marrow and then undergo engraftment, before differentiating into blood cells. ASCT is one of the most significant and innovative strategies for treating diseases. Here we focus on the treatment of Hodgkin's lymphoma, non-Hodgkin's lymphoma, multiple myeloma, and AL amyloidosis, using ASCT. This review provides a comprehensive picture of the effectiveness and the safety of ASCT as a therapeutic approach for these diseases, based on the currently available evidence.

Neural stem cells for Parkinson’s disease management: Challenges, nanobased support, and prospects

Parkinson’s disease (PD), characterized by loss of nigrostriatal dopaminergic neurons, is one of the most predominant neurodegenerative diseases affecting the elderly population worldwide. The concept of stem cell therapy in managing neurodegenerative diseases has evolved over the years and has recently rapidly progressed. Neural stem cells (NSCs) have a few key features, including self-renewal, proliferation, and multipotency, which make them a promising agent targeting neurodegeneration. It is generally agreed that challenges for NSC-based therapy are present at every stage of the transplantation process, including preoperative cell preparation and quality control, perioperative procedures, and postoperative graft preservation, adherence, and overall therapy success. In this review, we provided a comprehensive, careful, and critical discussion of experimental and clinical data alongside the pros and cons of NSC-based therapy in PD. Given the state-of-the-art accomplishments of stem cell therapy, gene therapy, and nanotechnology, we shed light on the perspective of complementing the advantages of each process by developing nano-stem cell therapy, which is currently a research hotspot. Although various obstacles and challenges remain, nano-stem cell therapy holds promise to cure PD, however, continuous improvement and development from the stage of laboratory experiments to the clinical application are necessary.