Pluripotent stem cell that can be isolated from body tissue
Objects of the present invention are to provide a method for directly obtaining pluripotent stem cells which do not have tumorigenic property from body tissue and the thus obtained pluripotent stem cells. The present invention relates to SSEA-3 (+) pluripotent stem cells that can be isolated from body tissue.
1. A method for preparing a cell fraction comprising 50% or more of multilineage-differentiating stress enduring cells (MUSE cells), comprising:
exposing mesenchymal cells derived from bone marrow, adipose tissue, skin, umbilical cord or blood to cellular stress conditions selected from the group consisting of low-oxygen culture conditions, serum starvation culture conditions, and sugar starvation culture conditions;
collecting survival cells;
separating the collected cells using SSEA-3 antigen marker as an index; and
recovering a cell fraction comprising 50% or more of MUSE cells,
wherein the MUSE cells in the recovered fraction are characterized by:
(i) SSEA-3(+) and CD105(+);
(ii) no telomerase activity or low telomerase activity as low as that of human fibroblasts;
(iii) the ability to differentiate into the three germ layers;
(iv) exhibit a lack of tumorigenesis;
(v) self-renewal capability; and
(vi) CD117(−) and CD146(−).
2. The method of claim 1 wherein the cellular stress is low-oxygen culture conditions.
3. The method of claim 2 wherein the low-oxygen culture conditions comprise 1% oxygen.
4. The method of claim 3 wherein the mesenchymal cells exposed to stress conditions are derived from bone marrow.
5. The method of claim 3 wherein the mesenchymal cells exposed to stress conditions are derived from adipose tissue.
6. The method of claim 3 wherein the recovered cell fraction comprises 70% or more of MUSE cells.
7. The method of claim 3 wherein the recovered cell fraction comprises 90% or more of MUSE cells.
8. The method of claim 3 wherein the recovered cell fraction comprises 95% or more of MUSE cells.