• Molecules and Cells
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• v.45 no.7
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• pp.479-494
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• 2022

Human mesenchymal stem cells (MSCs) are multipotent stem cells that have been intensively studied as therapeutic tools for a variety of disorders. To enhance the efficacy of MSCs, therapeutic genes are introduced using retroviral and lentiviral vectors. However, serious adverse events (SAEs) such as tumorigenesis can be induced by insertional mutagenesis. We generated lentiviral vectors encoding the wild-type herpes simplex virus thymidine kinase (HSV-TK) gene and a gene containing a point mutation that results in an alanine to histidine substitution at residue 168 (TK(A168H)) and transduced expression in MSCs (MSC-TK and MSC-TK(A168H)). Transduction of lentiviral vectors encoding the TK(A168H) mutant did not alter the proliferation capacity, mesodermal differentiation potential, or surface antigenicity of MSCs. The MSC-TK(A168H) cells were genetically stable, as shown by karyotyping. MSC-TK(A168H) responded to ganciclovir (GCV) with an half maximal inhibitory concentration (IC₅₀) value 10-fold less than that of MSC-TK. Because MSC-TK(A168H) cells were found to be non-tumorigenic, a U87-TK(A168H) subcutaneous tumor was used as a SAE-like condition and we evaluated the effect of valganciclovir (vGCV), an oral prodrug for GCV. U87-TK(A168H) tumors were more efficiently ablated by 200 mg/kg vGCV than U87-TK tumors. These results indicate that MSC-TK(A168H) cells appear to be pre-clinically safe for therapeutic use. We propose that genetic modification with HSV-TK(A168H) makes allogeneic MSC-based ex vivo therapy safer by eliminating transplanted cells during SAEs such as uncontrolled cell proliferation.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.10a
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• pp.78-78
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• 2003

Adult stem cells can make identical copies of themselves for long periods of time. They also give rise to many differentiated mature cell types that have characteristic morphology and specialized function. Human adult stem cells are the attractive raw materials for the cell/tissue therapy, however, it is not easy to get from the adult tissues. In the present study, we tried to isolate a cell population derived from human umbilical cord vein which has been discarded after birth. The cells were isolated after treatment of the umbilical vein with collagenase or trypsin. After 3 days of culture, two kinds of cell populations were found consisting of adherent cells with endothelial cell-like and fibroblast-like morphology, respectively. When these cells were subcultured 12 times over a period of 3 months, almost cells appeared uniformly to exhibit fibroblastoid morphology which was different from that of mesenchymal stem cells obtained from human bone marrow The results of RT-PCR analyses showed distinct expression of BMP-4, oct-4, and SCF genes but not of GATA, PAX-6 and Brachyury genes. On immunohistochemical staining, the cells were negative for the von Willebrand factor(vWF), alpha-smooth muscle actin and placental alkaline phosphatase. From these observations, it is suggested that stem-like cells might be present in human umbilical cord vein.

• International Journal of Stem Cells
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• v.17 no.1
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• pp.59-69
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• 2024

Human pluripotent stem cells (hPSCs) such as human embryonic stem cells (hESCs), induced pluripotent stem cells, and somatic cell nuclear transfer (SCNT)-hESCs can permanently self-renew while maintaining their capacity to differentiate into any type of somatic cells, thereby serving as an important cell source for cell therapy. However, there are persistent challenges in the application of hPSCs in clinical trials, where one of the most significant is graft rejection by the patient immune system in response to human leukocyte antigen (HLA) mismatch when transplants are obtained from an allogeneic (non-self) cell source. Homozygous SCNT-hESCs (homo-SCNT-hESCs) were used to simplify the clinical application and to reduce HLA mismatch. Here, we present a xeno-free protocol that confirms the efficient generation of neural precursor cells in hPSCs and also the differentiation of dopaminergic neurons. Additionally, there was no difference when comparing the HLA expression patterns of hESC, homo-SCNT-hESCs and hetero-SCNT-hESCs. We propose that there are no differences in the differentiation capacity and HLA expression among hPSCs that can be cultured in vitro. Thus, it is expected that homo-SCNT-hESCs will possess a wider range of applications when transplanted with neural precursor cells in the context of clinical trials.

• Korean Journal of Microbiology
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• v.42 no.1
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• pp.73-76
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• 2006

Neuronal precursor cells may provide for cell replacement or gene delivery vehicles in neurodegenerative disease therapy. One impediment to treating neuronal diseases is finding ways to introduce genes into neurons effectively. It is shown here that fiber-modified adenovirus vector delivered gene to neuronal precursor as well as differentiated neuronal cells more efficiently than first-generation adenoviral vector. Moreover, fiber-modified adenoviral vector transduced precursor cells retained the potential for differentiation into neurons and glia in vitro. These results show the potential of modified adenoviral vector in the improved gene delivery to neurons in direct gene therapy protocols. In addition it holds promise for the use of genetically manipulated stem cells for the therapy of neuronal diseases.

• Asian Oncology Nursing
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• v.8 no.1
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• pp.40-49
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• 2008

Purpose: This descriptive study was to investigate the quality of life in patients with hematopoietic stem cell transplantation (HSCT) from June 1 to October 13, 2007. Method: The survey was conducted in 6 different university hospitals which located in Seoul and Jeollanam-do province using the Functional Assessment of Cancer Therapy-BMT Scale (FACT-BMT) version 4. We collected a total of 155 questionnaires and analyzed 149 among them. Results: The average score of quality of life was 2.53 out of 5. Physical well being score was highest among sub-domains, followed by emotional well-being, additional concerns, social/family well-being, and functional well-being. Study subjects worried that their conditions would get worse. However study subjects didn't regret having been received HSCT. Age, duration from HSCT, age at diagnosis, income, readmission, HSCT type, educational background, marital status, and the level of activities of daily living were related to quality of life. Conclusions: The findings of this study indicates that the HSCT survivor's quality of life issue is still important and have to be investigated repeatedly in the future. That is necessary for generalizing QOL outcomes for clinical use. We also suggest to develop interventions to improve QOL.

• IMMUNE NETWORK
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• v.13 no.3
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• pp.107-110
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• 2013

Graft-versus-host disease (GVHD) is a common complication of allogeneic stem cell transplantation (allo-SCT). However, a similar syndrome has been reported in autologous stem cell transplantation (ASCT) as well. The target organs of GVHD in ASCT are the skin, liver and gastrointestinal (GI) tract, which are consistent with those in allo-SCT. Histologic findings from the skin and the mucosa of the GI tract also show similar features. Here we describe a case of autologous GVHD involving the skin of a patient who underwent ASCT for multiple myeloma. In this patient, the response to a total prednisone dose of 0.5 mg/kg/day was unsatisfactory, and the patient required more intensive and prolonged immunosuppressive therapy with slow tapering.

• Clinical and Experimental Reproductive Medicine
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• v.48 no.3
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• pp.268-272
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• 2021

Bone marrow-derived cell (BMDC) therapy has numerous applications as potential biological cells for use in regenerative medicine. Here, we present an original case of endometrial atrophy associated with genital tuberculosis in a woman who achieved a live birth with BMDC. This 27-year-old woman came to our center with endometrial atrophy and primary infertility. She had a past history of genital tuberculosis and amenorrhea. Her husband's semen quality was normal. The patient was counseled for hysteroscopy due to thin endometrium and advised in vitro fertilization (IVF) with donor eggs in lieu of poor ovarian reserve. Several attempts of IVF with hormone replacement therapy (HRT) were made, but the desired thickness of the endometrium was not achieved. Uterine artery injection of BMDC through interventional radiology was given, followed by HRT for three months, which resulted in improved endometrium. This was subsequently followed by IVF with donor egg. The treatment resulted in the conception and delivery of a 3.1-kg baby boy through lower segment caesarean section with no antenatal, intranatal or postnatal complications. Recently, there has been massive interest in stem cells as a novel treatment method for regenerative medicine, and more specifically for the regeneration of human endometrium disorders like Asherman syndrome and thin endometrium, which was the reason behind using this strategy for treatment.

• Korean Journal of Clinical Laboratory Science
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• v.50 no.4
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• pp.391-398
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• 2018

Mesenchymal stem cells (MSCs) are an attractive resource for refractory patients because of their anti-inflammatory/immunomodulatory capability and multi-lineage differentiation potential. The transplantation of MSCs has led to positive results in preclinical and clinical application to various diseases, including autoimmune disease, cardiovascular disease, cancer, liver cirrhosis, and ischemic stroke. On the other hand, studies have shown that paracrine factors, not direct cell replacement for damaged cells or tissue, are the main contributors in MSC-based therapy. More recently, evidence has indicated that MSC-derived exosomes play crucial roles in regulating the paracrine factors that can mediate tissue regeneration via transferring nucleic acids, proteins, and lipids to the local microenvironment and cell-to-cell communication. The use of these exosomes is likely to be beneficial for the therapeutic application of MSCs because their use can avoid harmful effects, such as tumor formation involved in cell transplantation. Therefore, therapeutic applications using MSC-derived exosomes might be safe and efficient strategies for regenerative medicine and tissue engineering. This review summarizes the recent advances and provides a comprehensive understanding of the role of MSC-derived exosomes as a therapeutic agent.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.9
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• pp.3715-3721
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• 2015

Leukemia is a clonal disorder with blocked normal differentiation and cell death of hematopoietic progenitor cells. Traditional modalities with most used radiation and chemotherapy are nonspecific and toxic which cause adverse effects on normal cells. Differentiation inducing therapy forcing malignant cells to undergo terminal differentiation has been proven to be a promising strategy. However, there is still scarce of potent differentiation inducing agents. We show here that Angelica sinensis polysaccharide (ASP), a major active component in Dong quai (Chinese Angelica sinensis), has potential differentiation inducing activity in human chronic erythro-megakaryoblastic leukemia K562 cells. MTT assays and flow cytometric analysis demonstrated that ASP inhibited K562 cell proliferation and arrested the cell cycle at the G0/G1 phase. ASP also triggered K562 cells to undergo erythroid differentiaton as revealed by morphological changes, intensive benzidine staining and hemoglobin colorimetric reaction, as well as increased expression of glycophorin A (GPA) protein. ASP induced redistribution of STAT5 protein from the cytoplasm to the nucleus. Western blotting analysis further identified that ASP markedly sensitized K562 cells to exogenous erythropoietin (EPO) by activating EPO-induced JAK2/STAT5 tyrosine phosphorylation, thus augmenting the EPO-mediated JAK2/STAT5 signaling pathway. On the basis of these findings, we propose that ASP might be developed as a potential candidate for chronic myelogenous leukemia inducing differentiation treatment.

• The Journal of Korean Physical Therapy
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• v.22 no.3
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• pp.79-85
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• 2010

Purpose: Many trials for new therapeutic approaches such as stem cell-based transplantation have been conducted to improve the repair and regeneration of injured cord tissue and to restore functions following spinal cord injury (SCI) in animals and humans. Adipose tissue-derived stromal cells (ATSCs) have multi-lineage potential to differentiate into cells with neuron-like morphology. Most studies of stem cell transplantation therapy after SCI are focused on cellular regeneration and restoration of motor function, but not on unwanted effects after transplantation such as neuropathic pain. This study was focused on whether transplantation of ATSCs could facilitate or attenuate hindpaw pain responses to heat, cold and mechanical stimulation, as well as on improvement of locomotor function in a rat with SCI. Methods: A spinal cord injury rat model was produced using an NYU impactor by dropping a 10 g rod from a height of 25 mm on to the T9 segment. Human ATSCs (hATSCs; approximately $5{\times}10^5$ cells) or DMEM were injected into the perilesional area 9 days after the SCI. After transplantation, hindpaw withdrawal responses to heat, cold and mechanical allodynia were measured over 7 weeks. Motor recovery on the Basso, Beattie, and Bresnahan (BBB) locomotor rating scale and on the inclined plane test were also evaluated. Results: The present study demonstrated that increased hindpaw withdrawal responses to cold allodynia was observed in both groups after transplantation, but the development of cold-induced allodynia in the hATSC transplantation group was significantly larger than in the control group. The difference between the two groups in locomotor functional improvement after SCI was also significant. Conclusion: Careful consideration not only of optimal functional benefits but also of unintended side effects such as neuropathic pain is necessary before stem cell transplantation therapy after SCI.