Intestinal stem cells contribute to the maturation of the neonatal small intestine and colon independently of digestive activity.

The murine intestine, like that of other mammalians, continues to develop after birth until weaning; however, whether this occurs in response to an intrinsic developmental program or food intake remains unclear. Here, we report a novel system for the allotransplantation of small intestine and colon harvested from Lgr5 ; Rosa26 mice immediately after birth into the subrenal capsule of wild-type mice. By histological and immunohistochemical analysis, the developmental process of transplanted small intestine and colon was shown to be comparable with that of the native tissues: mature intestines equipped with all cell types were formed, indicating that these organs do not require food intake for development.

Intestinal cancer stem cells marked by Bmi1 or Lgr5 expression contribute to tumor propagation via clonal expansion.

Although the existence of cancer stem cells in intestine tumors has been suggested, direct evidence has not been yet provided. Here, we showed, using the multicolor lineage-tracing method and mouse models of intestinal adenocarcinoma and adenoma that Bmi1- or Lgr5- positive tumorigenic cells clonally expanded in proliferating tumors. At tumor initiation and during tumor propagation in the colon, the descendants of Lgr5-positive cells clonally proliferated to form clusters.

Bmi1-positive cells in the lingual epithelium could serve as cancer stem cells in tongue cancer.

We recently reported that the polycomb complex protein Bmi1 is a marker for lingual epithelial stem cells (LESCs), which are involved in the long-term maintenance of lingual epithelial tissue in the physiological state. However, the precise role of LESCs in generating tongue tumors and Bmi1-positive cell lineage dynamics in tongue cancers are unclear. Here, using a mouse model of chemically (4-nitroquinoline-1-oxide: 4-NQO) induced tongue cancer and the multicolor lineage tracing method, we found that each unit of the tumor was generated by a single cell and that the assembly of such cells formed a polyclonal tumor.

Organoid Culture of Lingual Epithelial Cells in a Three-Dimensional Matrix.

A novel lingual epithelial organoid culture system using a three-dimensional (3D) matrix and growth factors has recently been established. In the culture system, organoids with multilayered squamous keratinized epithelium and typical morphological features of filiform papillae are generated from single lingual epithelial cells at a high efficiency. The culture system is created in order to observe the differentiation and maturation process of each lingual epithelial stem cell and to observe abnormal organoid formation from malignant cells obtained from carcinogen-treated mice.

Lingual Epithelial Stem Cells and Organoid Culture of Them.

As tongue cancer is one of the major malignant cancers in the world, understanding the mechanism of maintenance of lingual epithelial tissue, which is known to be the origin of tongue cancer, is unquestionably important. However, the actual stem cells that are responsible for the long-term maintenance of the lingual epithelium have not been identified. Moreover, a simple and convenient culture method for lingual epithelial stem cells has not yet been established.

Maintenance of sweat glands by stem cells located in the acral epithelium.

The skin is responsible for a variety of physiological functions and is critical for wound healing and repair. Therefore, the regenerative capacity of the skin is important. However, stem cells responsible for maintaining the acral epithelium had not previously been identified.

Bmi1 expression in long-term germ stem cells.

Asingle cells in undifferentiated spermatogonia are considered to be the most primitive forms of germ stem cells (GSCs). Although GFRα1 is thought to be a marker of Asingle cells, we found that Bmi1(High) is more specific than GFRα1 for Asingle cells. Bmi1(High) expression in Asingle cells is correlated with seminiferous stages, and its expression was followed by the proliferative stage of Asingle GSCs.

Establishment of a novel lingual organoid culture system: generation of organoids having mature keratinized epithelium from adult epithelial stem cells.

Despite the strong need for the establishment of a lingual epithelial cell culture system, a simple and convenient culture method has not yet been established. Here, we report the establishment of a novel lingual epithelium organoid culture system using a three-dimensional matrix and growth factors. Histological analyses showed that the generated organoids had both a stratified squamous epithelial cell layer and a stratum corneum.

Bone marrow-derived stromal cells can express neuronal markers by DHA/GPR40 signaling.

The exact origin of neural stem cells in the adult neurogenesis niche remains unknown. Our previous studies, however, indicated an implication of both bone marrow cells as potential progenitors of hippocampal newborn neurons and polyunsaturated fatty acids as ligands of G protein-coupled receptor 40 (GPR40) signaling. Here, we aimed at studying whether bone marrow-derived stromal cells (BMSC) treated by docosahexaenoic acid (DHA) can express neuronal markers in vitro.

Mouse mesenchymal stem cells can support human hematopoiesis both in vitro and in vivo: the crucial role of neural cell adhesion molecule.

Background: We previously established a mesenchymal stem cell line (FMS/PA6-P) from the bone marrow adherent cells of fetal mice. The cell line expresses a higher level of neural cell adhesion molecule and shows greater hematopoiesis-supporting capacity in mice than other murine stromal cell lines.

Design And Methods: Since there is 94% homology between human and murine neural cell adhesion molecule, we examined whether FMS/PA6-P cells support human hematopoiesis and whether neural cell adhesion molecules expressed on FMS/PA6-P cells contribute greatly to the human hematopoiesis-supporting ability of the cell line.

Transformation potential of bone marrow stromal cells into undifferentiated high-grade pleomorphic sarcoma.

Purpose: Bone marrow adherent cells contain conventional bone marrow stromal cells and mesenchymal stem cells and these cells constitute the hematopoietic microenvironment. Mesenchymal stem cells have the capacity to give rise to multiple mesenchymal lineage cells and even ectodermal lineage cells. In the present study, we investigated what types of tumor cells are inducible from BM adherent cells by chemical carcinogens.

Preferential expansion of human umbilical cord blood-derived CD34-positive cells on major histocompatibility complex-matched amnion-derived mesenchymal stem cells.

Background: We previously found in a murine hematopoietic system that hematopoietic stem cells show high differentiation and proliferation capacity on bone marrow-derived mesenchymal stem cells/stromal cells (microenvironment) with "self" major histocompatibility complex (MHC).

Design And Methods: We examined whether amnion-derived adherent cells have the characteristics of mesenchymal stem cells, and whether these adherent cells can support the proliferation of umbilical cord blood-derived lineage-negative and CD34-positive cells (Lin(-)CD34(+) cells) obtained from the same fetus to a greater extent than those derived from other fetuses.

Results: Culture-expanded amnion-derived adherent cells expressed mesenchymal stem cell markers and HLA-ABC molecules and could differentiate into osteoblasts, adipocytes and chondrocyte-like cells, indicating that the cells have the characteristics of mesenchymal stem cells.

Contribution of neural cell adhesion molecule (NCAM) to hemopoietic system in monkeys.

Neural cell adhesion molecules (CD56) are important adhesion molecules that are mainly expressed on neural cells and natural killer cells. Although freshly isolated cynomolgus monkey bone marrow cells (BMCs) contained only a few CD56-positive cells, almost all the BM adherent cells (obtained after a 2- to 3-week culture of the BMCs) were stained positively with anti-CD56 monoclonal antibody (mAb). The BM adherent cells showed uniformly fibroblastic morphology and were negative for hematolymphoid markers (CD4, CD8, CD11b, CD14, CD34, and CD45).

Successful acceptance of adult liver allografts by intra-bone marrow-bone marrow transplantation.

Previously, we have shown that liver allografts obtained from the fetus or young mice are accepted when bone marrow cells (BMCs) from adult mice of the same strain are co-grafted. However, for practical clinical use, it is more convenient to obtain both BMCs and liver from the same adult donors. C57BL/6 mice were irradiated with a single high-dose irradiation or two low-dose irradiations and injected with donor BALB/c (8 weeks old) BMCs intravenously (IV-BMT) or directly into the recipient BM cavity (IBM-BMT).

Facilitation of hematopoietic recovery by bone grafts with intra-bone marrow-bone marrow transplantation.

We have previously shown that T cells can acquire donor-type major histocompatibility complex (MHC) restriction and can interact with both donor-type antigen-presenting cells (APCs) and B cells, when adult donor bones are co-grafted with intravenous (IV) injection of bone marrow cells (BMCs) in order to supply donor bone marrow (BM) stromal cells. We have also found that the direct injection of donor BMCs into recipient BM (intra-bone marrow-bone marrow transplantation: IBM-BMT) produces more rapid reconstitution (including T-cell functions) and higher survival rates than IV injection (IV-BMT) even in chimerism-resistant combinations. In the present study, we show that the co-administration of bones from suckling (2-3 days old) donor mice is also effective in the IBM-BMT system.

Treatment of streptozotocin-induced diabetes mellitus in mice by intra-bone marrow bone marrow transplantation plus portal vein injection of beta cells induced from bone marrow cells.

Curative therapy for diabetes mellitus mainly involves pancreas or islet transplantation to recruit insulin-producing cells. This approach is limited, however, because of both the shortage of donor organs and allograft rejection. Intra-bone marrow bone marrow transplantation (IBM-BMT) has recently been shown to be effective in inducing donor-specific tolerance in mice and rats without the use of immunosuppressants.

Prevention of osteoporosis and hypogonadism by allogeneic ovarian transplantation in conjunction with intra-bone marrow-bone marrow transplantation.

Background: We investigated the effects of ovarian allograft in conjunction with intra-bone marrow-bone marrow transplantation (IBM-BMT) on estrogen deficiency in mice.

Methods: Female C57BL/6 mice underwent ovariectomy (OvX). After 3 months, the mice were irradiated at 9.

Effect of hepatocyte growth factor on long term hematopoiesis of human progenitor cells in transgenic-severe combined immunodeficiency mice.

Hepatocyte growth factor (HGF), which was originally isolated as a liver generating factor, enhances hematopoiesis. To study the effect of HGF on hematopoietic stem cells (HSCs) and hematopoietic progenitor cells (HPCs), we generated severe combined immunodeficiency (SCID) mice producing human (h) HGF and/or stem cell factor (SCF) by transferring the relevant genes to fertilized eggs, and then transplanted hematopoietic progenitors from human cord blood into the transgenic (Tg) SCID mice. Six months after transplantation, a significantly larger number of human cells were found in the Tg SCID mice than in non-Tg controls.

Extensive studies on perfusion method plus intra-bone marrow-bone marrow transplantation using cynomolgus monkeys.

The collection of bone marrow cells (BMCs) using a perfusion method has been advantageous not only because of the low contamination of BMCs with T cells from the peripheral blood but also the enrichment of stromal cells, which support hemopoiesis. Before the application of this new method to humans, its safety needed to be confirmed using cynomolgus monkeys. We therefore performed the perfusion method on more than 100 cynomolgus monkeys using the long bones (such as the humerus and femur) and also the iliac bones (for human application); in the more than 150 trials to date, there have been no accidental deaths.

The characteristics of hematopoietic stem cells from autoimmune-prone mice and the role of neural cell adhesion molecules in abnormal proliferation of these cells in MRL/lpr mice.

Background And Objectives: Using various animal models for autoimmune diseases, we have previously shown that such diseases are stem cell disorders.1 In order to understand how autoimmune diseases develop, we investigated the distinct qualitative differences between hematopoietic stem cells (HSC) from normal and autoimmune-prone mice.

Design And Methods: We studied the major histocompatibility complex (MHC) restriction between HSC and stromal cells in vitro and in vivo.

Analyses of very early hemopoietic regeneration after bone marrow transplantation: comparison of intravenous and intrabone marrow routes.

In bone marrow transplantation (BMT), bone marrow cells (BMCs) have traditionally been injected intravenously. However, remarkable advantages of BMT via the intra-bone-marrow (IBM) route (IBM-BMT) over the intravenous route (IV-BMT) have been recently documented by several laboratories. To clarify the mechanisms underlying these advantages, we analyzed the kinetics of hemopoietic regeneration after IBM-BMT or IV-BMT in normal strains of mice.

An innovative approach to bone marrow collection and transplantation in a patient with beta-thalassemia major: marrow collection using a perfusion method followed by intra-bone marrow injection of collected bone marrow cells.

Using small animals (mice and rats) and monkeys, we have found that the combination of bone marrow collection using the perfusion method (PM) and intra-bone marrow-bone marrow transplantation (IBM-BMT) of the collected cells is safe and effective in treating various intractable diseases. Based on these findings, we attempted to apply this method to humans. We report here the first case of a patient (6 years old) with beta-thalassemia major who underwent allogeneic BMT using this new PM + IBM-BMT method.

Treatment of senile osteoporosis in SAMP6 mice by intra-bone marrow injection of allogeneic bone marrow cells.

A substrain of the senescence-accelerated mouse, SAMP6 (senescence-accelerated mouse prone 6), spontaneously develops osteoporosis early in life. Therefore, this strain is a useful animal model for developing new strategies for the treatment of osteoporosis in humans. We succeeded in treating osteoporosis in SAMP6 mice after the onset of this disease, using a newly developed method of bone marrow transplantation (BMT): Allogeneic bone marrow cells obtained from normal mouse strains were directly injected into the bone marrow cavity of irradiated SAMP6 mice (intra-bone marrow BMT [IBM-BMT]).

Intra-bone marrow-bone marrow transplantation facilitates hemopoietic recovery including dendritic cells.

In this report, we provide evidence using a serial bone marrow transplantation (BMT) protocol that intra-bone marrow (IBM)-BMT (IBM-BMT) can efficiently reconstitute the hemopoietic system with cells of donor origin, in contrast to conventional intravenous (IV)-BMT (IV-BMT). Furthermore, the hematolymphoid system of secondary recipients that had received bone marrow cells (BMCs) from primary recipients treated with IBM-BMT recovered earlier than that of the secondary recipients of BMCs from primary recipients treated with IV-BMT. This was the case when the Lin-/c-kit+ progenitor cells of the secondary and tertiary recipients were examined.