Primate embryonic stem cells

Abstract

A purified preparation of primate embryonic stem cells is disclosed. This preparation is characterized by the following cell surface markers: SSEA-1 (−); SSEA-4 (+); TRA-1-60 (+); TRA-1-81 (+); and alkaline phosphatase (+). In a particularly advantageous embodiment, the cells of the preparation are human embryonic stem cells, have normal karyotypes, and continue to proliferate in an undifferentiated state after continuous culture for eleven months. The embryonic stem cell lines also retain the ability, throughout the culture, to form trophoblast and to differentiate into all tissues derived from all three embryonic germ layers (endoderm, mesoderm and ectoderm). A method for isolating a primate embryonic stem cell line is also disclosed.

1 - 11 . (canceled)  
     
     
         12 . A method of making differentiated human cells comprising the steps of 
 (a) obtaining a culture of human embryonic stem cells, the embryonic stem cells having the ability to develop into mesoderm, endoderm and ectoderm; and    (b) culturing the embryonic stem cells so that they differentiate into human cells selected from the group consisting of mesoderm, endoderm and ectoderm cells.    
     
     
         13 . A method as claimed in  claim 12  wherein the human embryonic stem cells are genetically engineered.  
     
     
         14 . Human differentiated cells in culture made by the method of  claim 12 .  
     
     
         15 . A method of making differentiated human cells in vitro comprising the steps of 
 (a) providing a culture of human embryonic stem cells, the embryonic stem cells having the properties of being euploid, maintenance of the potential to differentiate into mesoderm, endoderm and ectoderm, and that they are inhibited from differentiation when cultured on a fibroblast feeder layer; and    (b) culturing the embryonic stem cells in the absence of a fibroblast feeder layer such that the cells differentiate into human cells selected from the group consisting of mesoderm, endoderm and ectoderm.    
     
     
         16 . A method as claimed in  claim 15  wherein the human cells are genetically engineered.