Analysis of microRNA signatures using size-coded ligation-mediated PCR

The expression pattern and regulatory functions of microRNAs (miRNAs) are intensively investigated in various tissues, cell types and disorders. Differential miRNA expression signatures have been revealed in healthy and unhealthy tissues using high-throughput profiling methods. For further analyses of miRNA signatures in biological samples, we describe here a simple and efficient method to detect multiple miRNAs simultaneously in total RNA. The size-coded ligation-mediated polymerase chain reaction (SL-PCR) method is based on size-coded DNA probe hybridization in solution, followed-by ligation, PCR amplification and gel fractionation. The new method shows quantitative and specific detection of miRNAs. We profiled miRNAs of the let-7 family in a number of organisms, tissues and cell types and the results correspond with their incidence in the genome and reported expression levels. Finally, SL-PCR detected let-7 expression changes in human embryonic stem cells as they differentiate to neuron and also in young and aged mice brain and bone marrow. We conclude that the method can efficiently reveal miRNA signatures in a range of biological samples

Gene therapy in glioblastoma multiforme: Can it be a role changer?

Glioblastoma multiforme (GBM) is one of the most lethal cancers with a poor prognosis. Over the past century since its initial discovery and medical description, the development of effective treatments for this condition has seen limited progress. Despite numerous efforts, only a handful of drugs have gained approval for its treatment. However, these treatments have not yielded substantial improvements in both overall survival and progression-free survival rates. One reason for this is its unique features such as heterogeneity and difficulty of drug delivery because of two formidable barriers, namely the blood-brain barrier and the tumor-blood barrier. Over the past few years, significant developments in therapeutic approaches have given rise to promising novel and advanced therapies. Target-specific therapies, such as monoclonal antibodies (mAbs) and small molecules, stand as two important examples; however, they have not yielded a significant improvement in survival among GBM patients. Gene therapy, a relatively nascent advanced approach, holds promise as a potential treatment for cancer, particularly GBM. It possesses the potential to address the limitations of previous treatments and even newer advanced therapies like mAbs, owing to its distinct properties. This review aims to elucidate the current status and advancements in gene therapy for GBM treatment, while also presenting its future prospects

A review of animal models utilized in preclinical studies of approved gene therapy products: trends and insights

Abstract Scientific progress heavily relies on rigorous research, adherence to scientific standards, and transparent reporting. Animal models play a crucial role in advancing biomedical research, especially in the field of gene therapy. Animal models are vital tools in preclinical research, allowing scientists to predict outcomes and understand complex biological processes. The selection of appropriate animal models is critical, considering factors such as physiological and pathophysiological similarities, availability, and ethical considerations. Animal models continue to be indispensable tools in preclinical gene therapy research. Advancements in genetic engineering and model selection have improved the fidelity and relevance of these models. As gene therapy research progresses, careful consideration of animal models and transparent reporting will contribute to the development of effective therapies for various genetic disorders and diseases. This comprehensive review explores the use of animal models in preclinical gene therapy studies for approved products up to September 2023. The study encompasses 47 approved gene therapy products, with a focus on preclinical trials. This comprehensive analysis serves as a valuable reference for researchers in the gene therapy field, aiding in the selection of suitable animal models for their preclinical investigations

A comparison between osteogenic differentiation of human unrestricted somatic stem cells and mesenchymal stem cells from bone marrow and adipose tissue

To evaluate the potential of three stem cells for cell therapy and tissue engineering applications, the biological behavior and osteogenic capacity of the newly introduced cord-blood-derived, unrestricted somatic stem cells (USSC) were compared with those of mesenchymal stem cells isolated from bone marrow (BM-MSC) and adipose tissue (AT-MSC). There was no significant difference between the rates of proliferation of the three stem cells. During osteogenic differentiation, alkaline phosphatase (ALP) activity peaked on day 7 in USSC compared to BM-MSC which showed the maximum value of ALP activity on day 14. However, BM-MSC had the highest ALP activity and mineralization during osteogenic induction. In addition, AT-MSC showed the lowest capacity for mineralization during differentiation and had the lowest ALP activity on days 7 and 14. Although AT-MSC expressed higher levels of collagen type I, osteonectin and BMP-2 in undifferentiated state, but these genes were expressed higher in BM-MSC during differentiation. BM-MSC also expressed higher levels of ALP, osteocalcin and Runx2 during induction. Taking together, BM-MSC showed the highest capacity for osteogenic differentiation and hold promising potential for bone tissue engineering and cell therapy applications

Exploring non-viral methods for the delivery of CRISPR-Cas ribonucleoprotein to hematopoietic stem cells

Gene manipulation of hematopoietic stem cells (HSCs) using the CRISPR/Cas system as a potent genome editing tool holds immense promise for addressing hematologic disorders. An essential hurdle in advancing this treatment lies in effectively delivering CRISPR/Cas to HSCs. While various delivery formats exist, Ribonucleoprotein complex (RNP) emerges as a particularly efficient option. RNP complexes offer enhanced gene editing capabilities, devoid of viral vectors, with rapid activity and minimized off-target effects. Nevertheless, novel delivery methods such as microfluidic-based techniques, filtroporation, nanoparticles, and cell-penetrating peptides are continually evolving. This study aims to provide a comprehensive review of these methods and the recent research on delivery approaches of RNP complexes to HSCs

Clinical Application of Partial and Total Ossicular Replacement Prostheses of Hydroxyapatite Based Scaffolds Cultured with Human Mesenchymal Stromal Cells

Objective: To evaluate the feasibility of hydroxyapatite PORP and TORP as a scaffold with human mesenchymal stromal cells (hMSCs) and their use as replacement prosthesis during ossiculoplasty.Study Design: Application of tissue engineering in a prospective clinical study.Subjects and Methods: This study was conducted in 8 patients (6 canal wall down and 2intact canal wall tympanomastoidectomy) between April 2008 and June 2009.Prosthesis Preparation: In all the cases, 2 days before transplantation, hydroxyapatite implants were loaded by the cells obtained from culture obtained from patients’ own bone marrow. The cell suspension was applied to seed on scaffolds placed in 12-well tissue culture plates at a density of 2×106cells/scaffold. All pre and post operative audiometric evaluations (pure tone air and bone conduction thresholds) were carried out in the same center and by the same audiologist before and 3 months, 6 months , and one year after the operation.Setting: Otolaryngology, head and neck surgery department in a tertiary academic medical center.Results: The hMSCs were positive for CD10, CD44, CD166, CD106, HLA-ABC, CD90, CD54, and CD105, but were negative for CD34, CD45, CD117, and CD31. Mean air-bone gap closure was 19.57 dB. There was no sign of prosthesis extrusion at the end of twelve month follow-up period in all cases.Conclusion: The idea of tissue-engineered ear ossicles is a feasible and interesting option for the replacement of the ear ossicles. However, the final outcome needs longer follow-ups

Nasal septum-derived multipotent progenitors: A potent source for stem cell-based regenerative medicine

Thus far, autologous adult stem cells have attracted great attention for clinical purposes. In this study, we aimed at identifying and comprehensively characterizing a subpopulation of multipotent cells within human nasal septal cartilage. We also conducted a comparative investigation with other well-established stem cells such as bone marrow–mesenchymal stem cells, adipose tissue–mesenchymal stem cells, and unrestricted somatic stem cells. The isolated clonal population was characterized using immunofluorescence, flow cytometry, reverse transcriptase, and real-time polymerase chain reaction. Nasal septal progenitors (NSP) expressed critical pluripotency and mesoectodermal stem cell markers. They also shared many characteristics with MSC in expression of CD90, CD105, CD106, CD166, and HLA-ABC and lack of expression of CD34, CD45, and HLA-DR. NSP distinctly presented CD133 (Prominin-1). These cells could proliferate rapidly in vitro with a higher clonogenic potential and showed a longer lifespan than other studied cells. This population bears some other multipotent properties in showing a high capacity to be differentiated into other lineages including chondrocytes, osteocytes, and neural-like cell types. Another strong/positive feature of this population was their ability to be safely expanded ex vivo with no susceptibility to chromosomal abnormality or tumorigenicity both in vitro and in vivo. In conclusion, NSP could be considered as an alternative autologous cell source that can bring them to the top of therapeutic applications

Regenerative potential of multinucleated cells: bone marrow adiponectin-positive multinucleated cells take the lead

Abstract Background Polyploid cells can be found in a wide evolutionary spectrum of organisms. These cells are assumed to be involved in tissue regeneration and resistance to stressors. Although the appearance of large multinucleated cells (LMCs) in long-term culture of bone marrow (BM) mesenchymal cells has been reported, the presence and characteristics of such cells in native BM and their putative role in BM reconstitution following injury have not been fully investigated. Methods BM-derived LMCs were explored by time-lapse microscopy from the first hours post-isolation to assess their colony formation and plasticity. In addition, sub-lethally irradiated mice were killed every other day for four weeks to investigate the histopathological processes during BM regeneration. Moreover, LMCs from GFP transgenic mice were transplanted to BM-ablated recipients to evaluate their contribution to tissue reconstruction. Results BM-isolated LMCs produced mononucleated cells with characteristics of mesenchymal stromal cells. Time-series inspections of BM sections following irradiation revealed that LMCs are highly resistant to injury and originate mononucleated cells which reconstitute the tissue. The regeneration process was synchronized with a transient augmentation of adipocytes suggesting their contribution to tissue repair. Additionally, LMCs were found to be adiponectin positive linking the observations on multinucleation and adipogenesis to BM regeneration. Notably, transplantation of LMCs to myeloablated recipients could reconstitute both the hematopoietic system and BM stroma. Conclusions A population of resistant multinucleated cells reside in the BM that serves as the common origin of stromal and hematopoietic lineages with a key role in tissue regeneration. Furthermore, this study underscores the contribution of adipocytes in BM reconstruction. Graphical Abstrac

Early spontaneous immortalization and loss of plasticity of rabbit bone marrow mesenchymal stem cells

Objectives Bone marrow-derived mesenchymal stem cells (BM-MSC) have been widely used for cell therapy and tissue engineering purposes. However, there are still controversies concerning safety of application of these cells after in vitro expansion. Therefore, we aimed to investigate the characteristics of rabbit BM-MSC during long-term culture. Materials and methods In this study, we have examined growth kinetics, morphological changes, differentiation potential and chromosomal abnormalities, as well as tumour formation potential of rabbit BM-MSC in long-term culture. Results and conclusion We found that shortly after isolation, proliferation rate of rabbit BM-MSC decreases until they enter a dormant phase. During this period of quiescence, the cells are large and multinucleate. After some weeks of dormancy we found that several small mononuclear cells originated from each large multinucleate cell. These newly formed cells proliferated rapidly but had inferior differentiation potential. Although they were immortal, they did not have the capability for tumour formation in soft agar assay or in nude mice. This is the first report of spontaneous, non-tumorigenic immortalization of BM-MSC in rabbits. The phenomenon raises more concern for meticulous monitoring and quality control for using rabbit BM-MSC in cell-based therapies and tissue engineering experiments