Trophoblast cell preparations

Abstract

Stable pluripotent trophoblast stem (TS) cell lines and uses of the cell lines are described. The cell lines comprise cells that (i) are capable of indefinite proliferation in vitro in an undifferentiated state; and (ii) are capable of differentiation into cells of the trophoblast lineage in vivo.

1 . A stable pluripotent trophoblast stem (TS) cell line.  
     
     
         2 . A purified preparation of trophoblast stem cells which (i) are capable of indefinite proliferation in vitro in an undifferentiated state; and (ii) are capable of differentiation into cells of the trophoblast lineage in vivo.  
     
     
         3 . A purified preparation as claimed in  claim 2  which is further characterized by expression of genetic markers of diploid trophoblast cells.  
     
     
         4 . A purified preparation as claimed in  claim 2  wherein the cells are differentiated into cells of the trophoblast lineage.  
     
     
         5 . A purified cell preparation as claimed in  claim 4  characterized by expression of genetic markers of diploid trophoblast cells of the ectoplacental cone (EPC), and the secondary giant cells of the early conceptus.  
     
     
         6 . (canceled)  
     
     
         7 . A purified cell preparation as claimed in  claim 6  modified by introducing mutations into genes in the cells or by introducing transgenes into the cells.  
     
     
         8 . A method for producing a trophoblast cell line comprising culturing early postimplantation trophoblast cells or cells of a blastocyst on a feeder layer in the presence of FGF4, and a co-factor.  
     
     
         9 . A method as claimed in  claim 8  additionally comprising inducing differentiation of the cells of the cell line to cells of the trophoblast lineage by removing the FGF4, the co-factor, or the feeder layer.  
     
     
         10 . A method as claimed in  claim 8  wherein the early postimplantation trophoblast cells or cells of a blastocyst are isolated from a mammalian or marsupial species.  
     
     
         11 . A method as claimed in  claim 8  wherein the early postimplantation trophoblast cells or cells of a blastocyst are isolated from a rodent, rabbit, sheep, goat, pig, cattle, primate, or human.  
     
     
         12 . A method as claimed in  claim 8  wherein the early postimplantation trophoblast cells or cells of a blastocyst are transgenic.  
     
     
         13 . A method as claimed in  claim 8  wherein the feeder layer is a confluent fibroblast layer or a medium conditioned by primary embryonic fibroblast cells.  
     
     
         14 . A method as claimed in  claim 8  wherein the feeder layer comprises primary mouse embryonic fibroblast (EMFI) cells or STO cells.  
     
     
         15 . A method as claimed in  claim 8  wherein the FDF4 is recombinant FGF4 and the cofactor is heparin.  
     
     
         16 . A method as claimed in  claim 8  which further comprises introducing cells from the cell line into a blastocyst or aggregating the cells with an early stage embryo to produce chimeric conceptuses or placenta.  
     
     
         17 . A method as claimed in  claim 16  wherein the chimeric conceptuses or placenta are engineered to carry selectable markers or genetic alterations.  
     
     
         18 . A method as claimed in  claim 16  wherein cell lines are derived from the chimeric conceptuses or chimeric placenta.  
     
     
         19 . A chimeric conceptus derived from a purified preparation as claimed in  claim 2 .  
     
     
         20 . A chimeric placenta derived from a purified preparation as claimed in  claim 2 .  
     
     
         21 - 22 . (canceled)  
     
     
         23 . A method as claimed in claim  22  wherein the mammal is a human.