We have three big projects.
1．Regenerative Medicine using Amniotic Cells
Regenerative Medicine- cell therapy- requires three factors; cells for transplantation, growth factors which regulate cell growth and/or differentiation, and scaffolds which provide microenvironments for cell to grow and/or differentiate. Stem cells are expected to be used as cell for transplantation.
We focus on amnion derived cells as a cell source for cell therapy. Human anmion is a fetal origin tissue and is composed of a single layer of epithelial cells (human amnion epithelial cells, HAEs) on a thicker basement membrane and collagen spongy layer containing mesenchymal cells (human amnion mesenchymal cells, HAMs), that are derived from the inner cell mass in the blastocyst. It is suggested that amnion membrane including many stem cells since it is originated from fetal and differentiate at almost same time as Embryonic Stem Cells are derived.
Although amnion derived cells are attracted as a cell source for cell therapy, since it has stem cell like characters and low immunoregecity, very few research have been done with it. Thus, we have been researching on amniotic membranes and cells derived from them. Amniotic membrane was peeled mechanically from the chorion of a placenta obtained, with informed consent, after an uncomplicated Caesarean section.
a. Characterization of amniotic membrane
Histological characterization of amniotic membrane
Compared with other fetal origin tissues such as placenta, chorion, characteristic of amnion membrane will be specified.
Molecular biological characterization of amniotic membrane
Human amniotic epitherial cells (HAEs) and Human amniotic mesenchymal cells (HAMs) are analyzed by flowcytmetry, immunocytechemistry, and quantitative RT-PCR to characterize them as stem cells.
Immortarization of amnion derived cells
The weak point of amniotic cells is that they do not proliferate for long time. To overcome this problem, immortalized HAEs (iHAEs) and immortalized HAMs (iHAMs) have been established by introducing hTERT and E6/E7 genes by retrovisus infection. (collaborated with Dr. Tohru Kiyono, National Center of Cancer). Those iHAEs and iHAMs have been investigated gene expression, protein expression and differentiation into neural cells, osteocytes, chontrocytes and other specific cells.
b. Differentiation of amniotic cells into specific cells
One of the characters of stem cells is sphere formation. Isolate sphere forming cells from HAEs and differentiate into neuron, pancreatic beta cells and some other cells. Also, isolated better growing cells from HAMs and differentiate into bones, cartilages, adipose and cardiocytes.
c. Application for Therapy
iPS cells and bone marrow derived cells are not very good cell source for acute defects or disorders, because they have to be autogenic transplantation and it takes time for them to be cultured to get enough cells. Since amnion derived cells have low immunogenicity, they can be applied to allogenic transplantation and are expected to be a ready-made cell source.
Applying for Spinal cord injury
Spinal cord injury is one of the major acute defects and is known that it is very effective to be transplanted cells within two weeks after the defect. iHAMs are transplanted into Spinal cord injury model rats and observed their recovery for 3 months. Only rats transplanted iHAMs are functionally recovered in 10 days.
Also, we are trying to apply cells for alzheimer’s disease and diabetes.
2.Tissue engineering
a. Hyper-Dry Amniotic Membrane (HDMA)
Amniotic membranes dried with Hyper-Dry system using as a membrane more effectively are applying to several clinical treatments. Characters of HDAM are also investigated. This projects are collaborated with Departments of Ophthalmology, Oral surgery, brain surgery and otorhinolaryngology, University of Toyama.
b. Development of Medical Robot using bioprinting methods
Collaborating with Drs. Makoto Nakamura and Hideki Toda, Department of Technology, University of Toyama, Medical robots which analyze the images from human bodies and reconstruct that image by bioprinting method, injecting cells by the printer are developing.
3.Research on Cancer Stem Cells
Based on the hypothesis that cancer tissues include few cancer stem cells, these cancer stem cells from gynecological cancers and oral cancers are trying to be identified by analyzing gene expression, immunohistochemistry, and transplantation into mice models. Once those cancer stem cells are identified, they can be targets for screening new anti-cancer drugs.
