Selective antibody targeting of undifferentiated stem cells

A method of depleting undifferentiated stem cells from a cell population, comprising:

• a) obtaining a cell population that comprises both differentiated cells and undifferentiated stem cells;
• b) genetically altering undifferentiated stem cells in the population so that they contain a nucleic acid molecule comprising P-X, wherein X is nucleic acid sequence that causes expression of a cell surface antigen not normally expressed in the population, and P is a transcriptional control element operatively linked to X, such that the surface antigen is expressed in the undifferentiated stem cells;
• c) depleting undifferentiated cells from the population by combining the cells with a ligand specific for the antigen;
• and
• d) culturing the remaining differentiated cells.

A method for preparing cells, comprising:

• a) obtaining human embryonic stem (hES) cells that have been genetically altered so as to transcribe a nucleic acid sequence under control of a promoter that preferentially drives transcription in undifferentiated hES calls, wherein transcription of the nucleic acid causes expression of a surface antigen not normally expressed by undifferentiated hES cell;
• b) differentiating the hES cells;
• and then
• c) formulating the cells from step b) for administration to a mammalian host.

A method of depicting undifferentiated stem cells from a mixed cell population, comprising:

• a) obtaining a mixed cell population that comprises both differentiated cells and undifferentiated human embryonic stem (hES) calls;
• b) genetically altering the hES cells in the mixed cell population so as to transcribe a nucleic acid sequence under control of a promoter that preferentially drives transcription in undifferentiated hES cells, wherein transcription of the nucleic acid causes expression of a surface antigen not normally expressed by undifferentiated hES cells, thereby producing a genetically altered cell population;
• c) depleting undifferentiated cells from the genetically altered cell population by using a lectin or antibody specific for the antigen, thereby producing a more homogeneous cell population;
• and
• d) formulating the more homogeneous cell population for administration to a mammalian host.