Biology subjects

UMEZAWA, A.

Publications and source records attributed to UMEZAWA, A..

9 recordsLinked to original sources

bioRxiv2024

Automated Xeno-Free Chondrogenic Differentiation from Human Embryonic Stem Cells: Enhancing Efficiency and Ensuring High-Quality Mass Production

IntroductionRepairing damaged cartilage poses significant challenges, particularly in cases of congenital cartilage defects such as microtia or congenital tracheal stenosis, or as a consequence of traumatic injury, as the regenerative potential of cartilage is inherently limited. Stem cell therapy and tissue engineering offer promising approaches to overcome these limitations in cartilage healing. However, the challenge lies in the size of cartilage-containing organs, which necessitates a large quantity of cells to fill the damaged areas. Therefore, pluripotent stem cells that can proliferate indefinitely are highly desirable as a cell source. This study aims to delineate the differentiation conditions for cartilage derived from human embryonic stem cells (ESCs) and to develop an automated cell culture system to facilitate mass production for therapeutic applications. MethodsCartilage cell sheets were derived from human ESCs (SEES2, clinical trial-compatible line) by forming embryoid bodies (EBs) with either conventional manual culture or a benchtop multi-pipetter and an automated medium exchange integrated cell incubator, using xeno-free media. Cell sheets were implanted into the subcutaneous tissue of immunodeficient NOG mice to obtain cartilage tissue. The properties of cartilage tissues were examined by histological staining and quantitative PCR analysis. ResultsWe have optimized an efficient xeno-free system for cartilage production with the conventional culture method and successfully transitioned to an automated system. Differentiated cartilage was histologically uniform with cartilage-specific elasticity and strength. The cartilage tissues were stained by alcian blue, safranin O, and toluidine blue, and quantitative PCR showed an increase in differentiation markers such as ACAN, COL2A1, and Vimentin. Automation significantly enhanced the efficiency of human ESC-derived chondrocyte differentiation. The number of constituent cells within EBs and the seeding density of EBs were identified as key factors influencing chondrogenic differentiation efficiency. By automating the process of chondrogenic differentiation, we achieved scalable production of chondrocytes. ConclusionsBy integrating the differentiation protocol with an automated cell culture system, there is potential to produce cartilage of sufficient size for clinical applications in humans. The resulting cartilage tissue holds promise for clinical use in repairing organs such as the trachea, joints, ears, and nose.

cell biology↗

bioRxiv2023

Human intestinal organoid-derived PDGFRα+ mesenchymal stroma empowers LGR4+ epithelial stem cells

The columnar epithelial cells comprising the intestinal tract, stomach, and uterus can be cultured in vitro as organoids or in adherent culture. However, the proliferation of these columnar epithelial cells in adherent culture is limited. Likewise, human pluripotent stem cell (hPSC)-derived intestinal epithelial cells do not show extensive or clonal propagation in vitro. In this study, we induced proliferation of hPSC-derived small intestinal epithelium for a longer time by utilizing mesenchymal stromal cells derived from self-organized intestinal organoids as feeders. The proliferating cells exhibited columnar form, microvilli and glycocalyx formation, and cell polarity, as well as expression of drug-metabolizing enzymes and transporters. It is noteworthy that small intestinal epithelial stem cells cannot be cultured in adherent culture alone, and the stromal cells cannot be replaced by other feeders. Organoid-derived mesenchymal stromal cells resemble the trophocytes essential for maintaining small intestinal epithelial stem cells, and play a crucial role in adherent culture. The high proliferative expansion, productivity, and functionality of hPSC-derived small intestinal epithelial stem cells could have potential applications in pharmacokinetic and toxicity studies and regenerative medicine.

cell biology↗

bioRxiv2023

Functional and long-lived melanocytes from human pluripotent stem cells with transient ectopic expression of JMJD3

BackgroundMelanocytes are an essential part of the epidermis, and their regeneration has received much attention because propagation of human adult melanocytes in vitro is too slow for clinical use. Differentiation from human pluripotent stem cells to melanocytes has been reported, but the protocols to produce them require multiple and complex differentiation steps. MethodWe differentiated human embryonic stem cells (hESCs) that transiently express JMJD3 to pigmented cells. We investigated whether the pigmented cells have melanocytic characteristics and functions by qRT-PCR, immunocytochemical analysis and flow cytometry. We also investigated their biocompatibility by injecting the cells into immunodeficient mice for clinical use. ResultWe successfully differentiated and established a pure culture of melanocytes. The melanocytes maintained their growth rate for a long time, approximately 200 days, and were functional. They exhibited melanogenesis and transfer of melanin to peripheral keratinocytes. Moreover, melanocytes simulated the developmental processes from melanoblasts to melanocytes. The melanocytes had high engraftability and biocompatibility in the immunodeficient mice. ConclusionThe robust generation of functional and long-lived melanocytes are key to developing clinical applications for the treatment of pigmentary skin disorders.

cell biology↗

bioRxiv2022

Novel therapeutic strategies for injured endometrium: Autologous intrauterine transplantation of menstrual blood-derived cells from infertile patients

BackgroundMenstrual blood-derived cells show regenerative potential as a mesenchymal stem cell and may therefore be a novel stem cell source of treatment for refractory infertility with injured endometrium. However, there have been few pre-clinical studies using cells from infertile patients, which needs to be addressed before establishing an autologous transplantation. Herein, we aimed to investigate the therapeutic capacity of menstrual blood-derived cells from infertile patients on endometrial infertility. MethodsWe collected menstrual blood-derived cells from volunteers and infertile patients, and confirmed their mesenchymal stem cell phenotype by flowcytometry and induction of tri-lineage differentiation. We compared the proliferative and paracrine capacities of these cells. Furthermore, we also investigated the regenerative potential and safety concerns of the intrauterine transplantation of infertile patient-derived cells using a mouse model with mechanically injured endometrium. ResultsMenstrual blood-derived cells from both infertile patients and volunteers showed phenotypic characteristics of mesenchymal stem cells. In vitro proliferative and paracrine capacities for wound healing and angiogenesis were equal for both samples. Furthermore, the transplantation of infertile patient-derived cells into uterine horns of the mouse model ameliorated endometrial thickness, prevented fibrosis and improved fertility outcomes without any apparent complications. ConclusionsIn our preclinical study, intrauterine transplantation of menstrual blood-derived cells may be a novel and attractive stem cell source for the curative and prophylactic therapy for injured endometrium. Further studies will be warranted for future clinical application.

cell biology↗

bioRxiv2021

Hepatocytes with a phenotype of substantial CYP3A4 induction generated from drug-associated fulminant hepatitis-derived induced pluripotent stem cells

Hepatocyte-like cells (HLCs) generated from human pluripotent stem cells (PSCs) exhibit hepatocytic properties in vitro; however, their engraftment and functionality in vivo remain unsatisfactory. Despite optimization of differentiation protocols, HLCs did not engraft in a mouse model of liver injury. In contrast, organ-derived hepatocytes reproducibly formed colonies in the liver injury mouse model. As an extension of the phenomenon observed in hematopoietic stem cells giving rise to colonies within the spleen, commonly referred to as "colony-forming units in spleen (CFU-s", we hypothesize that "colony-forming units in liver (CFU-L)" serves as a reliable indicator of stemness, engraftment, and functionality of hepatocytes. The uniform expression of the randomly inactivated gene in a single colony, as reported by Sugahara et al. 2022, suggests that the colonies generated by isolated hepatocytes likely originate from a single cell. We, therefore, propose that CFU-L can be used to quantify the number of "hepatocytes that engraft and proliferate in vivo" as a quantitative assay for stem cells that utilize colony-forming ability, similar to that observed in hematopoietic stem cells.

cell biology↗

bioRxiv2021

Drug metabolism activity is a Critical Intrinsic Selector for Hepatocytes to elongate cell lifespan by using a cell-killing antibiotic

Hepatocytes can be used to study the pathogenesis of liver diseases and drug discovery research. Human hepatocytes are, however, hardly expandable in vitro making it difficult to secure large numbers of cells from one donor. In this study, we aimed to establish an in vitro long-term culture system that enables stable proliferation and maintenance of human hepatocytes to ensure a constant supply. We purified human hepatocytes by selection with cytocidal puromycin, and cultured them for more than 60 population doublings over a span of more than 350 days. These results show that this simple culture system with usage of the cytocidal antibiotics enables efficient hepatocyte proliferation and is an effective method for generating a stable supply of hepatocytes for drug discovery research at a significant cost reduction.

cell biology↗

bioRxiv2019

Gorlin syndrome-induced pluripotent stem cells form medulloblastoma with loss of heterozygosity in PTCH1

Gorlin syndrome is a rare autosomal dominant hereditary disease with high incidence of tumors such as basal cell carcinoma and medulloblastoma. Disease-specific induced pluripotent stem cells (iPSCs) have now been used as a model to analyze disease pathogenesis as well as an animal model. In this study, we generated iPSCs derived from fibroblasts of four patients with Gorlin syndrome (Gln-iPSCs) with a heterozygous mutation of the PTCH1 gene. Gln-iPSCs from the four patients developed medulloblastoma in 100% (four out of four), a manifestation of Gorlin syndrome, in the teratomas after implantation into immunodeficient mice, but none (0/584) of the other iPSC-teratomas. One of the medulloblastomas had loss of heterozygosity in the PTCH1 gene while benign teratoma, i.e. non-medulloblastoma part, did not, indicating a close clinical correlation between tumorigenesis in Gorlin syndrome patients and Gln-iPSCs.

cell biology↗

bioRxiv2016

Fetal therapy model of myelomeningocele with three-dimensional skin using amniotic fluid cell-derived induced pluripotent stem cells

Myelomeningocele (MMC) is a congenital disease without genetic abnormalities. Neurological symptoms are irreversibly impaired after birth. No effective treatment has been reported to date. Only surgical repairs have reported so far. In this study, we performed antenatal treatment of MMC with an artificial skin using induced pluripotent stem cells (iPSCs) generated from a patient with Down syndrome (AF-T21-iPSCs) and twin-twin transfusion syndrome (AF-TTTS-iPSCs) to a rat model. We manufactured three-dimensional skin with epidermis generated from keratinocytes derived from AF-T21-iPSCs and AF-TTTS-iPSCs and dermis of human fibroblasts and collagen type I. For generation of epidermis, we developed a novel protocol using Y-27632 and epidermal growth factor. The artificial skin was successfully covered over MMC defect sites during pregnancy, implying a possible antenatal surgical treatment with iPSC technology.

cell biology↗

bioRxiv2016

Pharmaceutical efficacy of human epiphyseal chondrocytes with differential replication numbers for cellular therapy products

The cell-based therapy for cartilage or bone requires a large number of cells serial passages of chondrocytes are, therefore, needed. However, fates of expanded chondrocytes from extra fingers remains unclarified. The chondrocytes from human epiphyses morphologically changed from small polygonal cells, to bipolar elongated spindle cells and to large polygonal cells with degeneration at early passages. Gene of type II collagen was expressed in the cells only at a primary culture (Passage 0) and Passage 1 (P1) cells. The nodules by implantation of P0 to P8 cells were composed of cartilage and perichondrium. The cartilage consisted of chondrocytes with round nuclei and type II collagen-positive matrix, and the perichondrium consisted of spindle cells with type I collage-positive matrix. The cartilage and perichondrium developed to bone with marrow cavity through enchondral ossification. Chondrogenesis and osteogenesis by epiphyseal chondrocytes depended on replication number in culture. It is noteworthy to take population doubling level in correlation with pharmaceutical efficacy into consideration when we use chondrocytes for cell-based therapies.

cell biology↗