Somatic pluripotent cells

Patent Number: 7,422,736

Numerous patents exist on various types of stem cells.  For example, Osiris has overarching patents on any cell that expresses the mesenchymal stem cell markers SH2, SH3, or SH4.  An example of which is US patent # 5,486,359, in which the broadest claim covers "An isolated, homogeneous population of human mesenchymal stem cells which can differentiate into cells of more than one connective tissue type".  Other companies, such as one of the ones owned by Angioblast Systems (# 7,399,632) cover methods of generating mesenchymal stem cells, with claims such as "A method of preparing a population of cells enriched for mesenchymal precursor cells, comprising treating the population of cells so as to enrich for cells which are STRO-1.sup.bright".

The current patent teaches how to generate pluripotent stem cells by isolating mesenchymal stem cells, placing the stem cells under low serum conditions for several days and selecting cells from the cells that have been starved, for ability to form teratomas as a means of assessing pluripotency.  The pluripotent stem cells are SSEA-1 negative and may be collected from mesenchymal stem cells of a variety of tissues including bone marrow, blood, cord blood, and placenta.  They do not cover menstrual blood derived stem cells as the endometrial regenerative cell discover by Medistem.

This patent will be useful for parties seeking to develop novel stem cell approaches, however it is still not clear whether they require freedom to operated based on the patents previously discussed.

View this patent on the USPTO website.