Pdx1-expressing dorsal and ventral foregut endoderm

Abstract

Disclosed herein are cell cultures comprising dorsal and/or ventral PDX1-positive foregut endoderm cells and methods of producing the same. Also disclosed herein are cell populations comprising substantially purified dorsal and/or ventral PDX1-positive foregut endoderm cells as well as methods for enriching, isolating and purifying dorsal and/or ventral PDX1-positive foregut endoderm cells from other cell types. Methods of identifying differentiation factors capable of promoting the differentiation of dorsal and/or ventral PDX1-positive foregut endoderm cells, are also disclosed.

What is claimed is: 
     
         1 . A method of producing human foregut endoderm cells, the method comprising:
 culturing definitive endoderm cells in a medium wherein the medium is either   a) substantially free of TGFβ superfamily growth factor; or   b) comprises a FGF-family growth factor   thereby producing human foregut endoderm cells.   
     
     
         2 . A method of producing human foregut endoderm cells, the method comprising: culturing definitive endoderm cells in a medium substantially free of a TGFβ superfamily growth factor thereby producing human foregut endoderm cells. 
     
     
         3 . A method of producing human foregut endoderm cells, the method comprising: culturing definitive endoderm cells in a medium comprising a FGF-family growth factor thereby producing human foregut endoderm cells. 
     
     
         4 . The method of  claim 1 , wherein the definitive endoderm cells are cultured in a medium substantially free of TGFβ superfamily growth factor and comprising a FGF-family growth factor. 
     
     
         5 . The method of  claim 1 , wherein the foregut endoderm cells express a marker selected from the group consisting of SOX17, HNF1β and FOXA1 and do not substantially express pancreatic-duodenal homeobox factor-1 (PDX1). 
     
     
         6 . The method of  claim 1 , wherein at least 10% of the human cells are foregut endoderm cells that express a marker selected from the group consisting of SOX17, HNF1β and FOXA1, and do not substantially express PDX1. 
     
     
         7 . The method of  claim 1 , wherein at least 25% of the human cells are foregut endoderm cells that express a marker selected from the group consisting of SOX17, HNF1β and FOXA1, and do not substantially express PDX1. 
     
     
         8 . The method of  claim 1 , wherein the foregut endoderm cells express the SOX17, HNF1β and FOXA1 markers, and do not substantially express PDX1. 
     
     
         9 . The method of  claim 1 , wherein the foregut endoderm cells do not substantially express CER, and do not substantially express PDX1. 
     
     
         10 . The method of  claim 1 , wherein the FGF-family growth factor comprises FGF −7. 
     
     
         11 . The method of  claim 1 , wherein the cell culture is substantially free of cells selected from the group consisting of visceral endoderm cells, parietal endoderm cells and neural cells. 
     
     
         12 . The method of  claim 1 , wherein the foregut endoderm cells are multipotent cells that can further differentiate to cells derived from the foregut. 
     
     
         13 . The method of  claim 1 , wherein the foregut endoderm cells to not and do not substantially express PDX1. 
     
     
         14 . The method of  claim 1 , wherein the medium comprises a retinoid or a hedgehog inhibitor. 
     
     
         15 . The method of  claim 2 , wherein the medium comprises a retinoid or a hedgehog inhibitor. 
     
     
         16 . The method of  claim 3 , wherein the medium comprises a retinoid or a hedgehog inhibitor. 
     
     
         17 . The method of  claim 1 , wherein the TGFβ superfamily member is selected from the group comprising nodal, activin A, activin B or BMP4. 
     
     
         18 . The method of  claim 14 , wherein the hedgehog inhibitor is KAAD-cyclopamine. 
     
     
         19 . The method of  claim 14 , wherein the retinoid is retinoic acid. 
     
     
         20 . The method of  claim 1 , wherein the medium is substantially free of a compound selected from the group consisting of EGF and bFGF.