FIELD OF THE INVENTION

The present invention relates to a stem cell removing method, a differentiated cell protective method, and culture medium composition, and, especially, it is related with a stem cell removing method, a differentiated cell protective method, and culture medium composition when making a pluripotent stem cell differentiate.

BACKGROUND OF THE INVENTION

An ES cell (Embryonic Stem Cells, ESCs) or an induced pluripotent stem cell (Induced Pluripotent Stem Cells, iPSCs) is a kind of a cell called a pluripotent stem cell (Pluripotent Stem Cell), and it is in an undifferentiated state and has capability where differentiation induction to the cells of all three germ layers is possible. Therefore, using a human pluripotent stem cell for a regenerative medicine of various diseases is expected, potentially.

When using the pluripotent stem cell for regenerative medicine, it is necessary to transplant to the living body in a state where differentiation induction has performed to cell groups, such as a specific cell, a tissue, or an internal organ.

For example, as refer to patent documents 1, it is disclosed a manufacturing method of a nerve cell sheet having a nerve cell layer formed of a nerve cell performed axis cylinder expansion including the steps of: culturing a nerve cell sheet having the lamina ganglionaris formed of the cultured nerve cell which performed axis cylinder expansion and a precursor cell in culture solution including a Sonic hedgehog inhibitor and a differentiation inducer, and inducing nerve cell from the precursor cell; and culturing a nerve cell in culture solution including at least one of SDF 1 (Stromal cells-derived factor-1) and MCP-1 (Monocyte chemoattractant propein-1), axis cylinder expansion of a nerve cell is induced, and obtaining the nerve cell layer formed of the cultured nerve cell performed axis cylinder expansion.

PRIOR ART DOCUMENT

Patent Documents

[Patent documents 1] JP2014-23457A

SUMMARY OF THE INVENTION

Problem(s) to be Solved by the Invention

However, if a pluripotent stem cell having an undifferentiated state is mixed in a cell group performed differentiation induction as like the technology of patent documents 1, since teratoma (teratoid tumor) occurs in vivo, it needs to be selected only the differentiated cell. Also, in case that differentiation induction of the somatic stem cell with the capability to differentiate to a specific cell line is performed and the somatic cell is manufactured, if the undifferentiated somatic stem cell remained, it might become causes, such as other tumors (Hereinafter, various stem cells including a pluripotent stem cell and a somatic stem cell are just called as a “stem cell”.). Therefore, it is anxious for technology of efficiently-removing the stem cell from the cell group performed differentiation induction.

The present invention is accomplished in view of such a situation, and an object of the present invention is to solve the above-mentioned problem.

Means for Solving the Problem

A stem cell removing method of the present invention includes the steps of: cultivating a cell group including a stem cell and a somatic cell performed differentiation induction from the stem cell in culture medium composition including photosensitizer; irradiating with light of a specific wavelength to the cell group cultivated in the culture medium composition including the photosensitizer; and removing the stem cell from the cell group.

The stem cell removing method of the present invention is, wherein the stem cell is a pluripotent stem cell or a somatic stem cell; and the pluripotent stem cell includes an ES cell (Embryonic Stem Cell) or an iPS cell (induced Pluripotent Stem Cell), and the somatic stem cell includes anyone of a germ stem cell, a productive cell, a pluripotent stem cell and a stem cell having unipotency.

The stem cell removing method of the present invention is, wherein the photosensitizer is aminolevulinic acid (Amino Levulinic Acid), a derivative thereof, or a salt thereof.

The stem cell removing method of the present invention is, wherein concentration of the aminolevulinic acid, the derivative thereof, or the salt thereof is 10 micro-M to 2000 micro-M.

The stem cell removing method of the present invention is, wherein time until photoirradiation after adding the aminolevulinic acid, the derivative thereof, or the salt thereof is 4 hours or more.

The stem cell removing method of the present invention is, wherein wavelength of the light of the specific wavelength is 400 nm to 750 nm, the irradiation intensity is 1 mW/cm2to 200 mW/cm2, and the irradiation time is 1 minute to 240 minutes.

A differentiated cell protective method of the present invention includes a step of protecting the somatic cell performed the differentiation induction when being removed by the stem cell removing method.

The differentiated cell protective method of the present invention is, wherein protected somatic cell is a mesoblast system cell.

The differentiated cell protective method of the present invention is, wherein protected somatic cell is an ectoderm system cell.

The differentiated cell protective method of the present invention is, wherein protected somatic cell is an endoderm system cell.

A culture medium composition of the present invention includes: a medium component for cultivating a cell group including a stem cell and a somatic cell performed differentiation induction from the stem cell; and photosensitizer.

The culture medium composition of the present invention is, wherein removes the stem cell when irradiating with light of a specific wavelength.

The culture medium composition of the present invention is, wherein protects the somatic cell performed differentiation induction when irradiating with the light of the specific wavelength.

The culture medium composition of the present invention is, wherein the stem cell is a pluripotent stem cell or a somatic stem cell, the pluripotent stem cell includes an ES cell (Embryonic Stem Cell) or an iPS cell (induced Pluripotent Stem Cell), and the somatic stem cell is a cell having pluripotency and self-replication ability.

The culture medium composition of the present invention is, wherein the somatic cell performed differentiation induction from the stem cell includes any one of the group consisting of a mesoblast system cell, an ectoderm system cell, and an endoderm system cell.

The culture medium composition of the present invention is, further includes a growth factor component that performs differentiation induction of the somatic cell from the stem cell.

The culture medium composition of the present invention is, wherein the medium component includes nutritional component for giving nutritive substance to a cell.

The culture medium composition of the present invention is, wherein the medium component includes a buffer component for keeping environment under cultivation constant.

The Culture medium composition of the present invention is, wherein the medium component includes a growth promotion component that promotes growth of the somatic cell.

The culture medium composition of the present invention is, wherein the photosensitizer is aminolevulinic acid (Amino Levulinic Acid), a derivative thereof, or a salt thereof.

The culture medium composition of the present invention is, wherein concentration of the aminolevulinic acid, the derivative thereof, or the salt thereof is 10 micro-M to 2000 micro-M.

The culture medium composition of the present invention is, wherein time until photoirradiation is performed after adding the aminolevulinic acid, derivative thereof, or salt thereof is 4 hours or more.

The culture medium composition of the present invention is, wherein wavelength of the light of the specific wavelength is 400 nm to 750 nm, the irradiation intensity is 1 mW/cm2to 200 mW/cm2, and the irradiation time is 1 minute to 240 minutes.

Effect of the Invention

According to the present invention, technology can be provided that, by irradiating light of a specific wavelength to a cell group cultivated by culture medium composition including photosensitizer, a stem cell is easily removed from a cell group including a somatic cell performed differentiation induction and the stem cell.

