Publications by authors named "Masakazu Machida"

Introduction: Human induced pluripotent stem cells (hiPSCs) are generated through the reprogramming of somatic cells expressing a defined set of transcription factors. The advent of autologous iPSCs has enabled the generation of patient-specific iPSC lines and is expected to contribute to the exploration of cures and causes of diseases, drug screening, and tailor-made regenerative medicines. Efficient control of hiPSC derivation is beneficial for industrial applications.

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A large number of myocytes are necessary to treat intractable muscular disorders such as Duchenne muscular dystrophy with cell-based therapies. However, starting materials for cellular therapy products such as myoblasts, marrow stromal cells, menstrual blood-derived cells, and placenta-derived cells have a limited lifespan and cease to proliferate in vitro. From the viewpoints of manufacturing and quality control, cells with a long lifespan are more suitable as a starting material.

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Functional intestines are composed of cell types from all 3 primary germ layers and are generated through a highly orchestrated and serial developmental process. Directed differentiation of human pluripotent stem cells (hPSCs) has been shown to yield gut-specific cell types; however, these structures do not reproduce critical functional interactions between cell types of different germ layers. Here, we developed a simple protocol for the generation of mature functional intestinal organoids from hPSCs under xenogeneic-free conditions.

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Transformation of human embryonic stem cells (hESC) is of interest to scientists who use them as a raw material for cell-processed therapeutic products. However, the WHO and ICH guidelines provide only study design advice and general principles for tumorigenicity tests. In this study, we performed in vivo tumorigenicity tests (teratoma formation) and genome-wide sequencing analysis of undifferentiated hESCs i.

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The potential applications of human embryonic stem cells (hESCs) in regenerative medicine and developmental research have made stem cell biology one of the most fascinating and rapidly expanding fields of biomedicine. The first clinical trial of hESCs in humans has begun, and the field of stem cell therapy has just entered a new era. Here, we report seven hESC lines (SEES-1, -2, -3, -4, -5, -6, and -7).

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We generated transgenic silkworms that synthesized human type I collagen alpha1 chain [alpha1(I) chain] in the middle silk glands and secreted it into cocoons. The initial content of the recombinant alpha1(I) chain in the cocoons of the transgenic silkworms was 0.8%.

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We have previously demonstrated that the tetraspanin CD9 is necessary for membrane fusion between sperm and oocyte during fertilization. While knockout mice for CD9 are viable, CD9(-/-) females are sterile due to the inability of their oocytes to fuse with sperm. While CD9 is not essential for subsequent development, a role in embryonic stem (ES) cell self-renewal was hypothesised on the basis of two observations: CD9 is highly expressed in murine and human ES cells and the CD9-blocking antibody inhibits mouse ES cell colony formation and survival.

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POU5F1 (more commonly known as OCT4/3) is one of the stem cell markers, and affects direction of differentiation in embryonic stem cells. To investigate whether cells of mesenchymal origin acquire embryonic phenotypes, we generated human cells of mesodermal origin with overexpression of the chimeric OCT4/3 gene with physiological co-activator EWS (product of the EWSR1 gene), which is driven by the potent EWS promoter by translocation. The cells expressed embryonic stem cell genes such as NANOG, lost mesenchymal phenotypes, and exhibited embryonal stem cell-like alveolar structures when implanted into the subcutaneous tissue of immunodeficient mice.

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