PDX1 expressing endoderm

Abstract

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

1 . A cell culture comprising human cells, wherein at least about 2% of said human cells are pancreatic-duodenal homoebox factor-1 (PDX1) positive foregut endoderm cells, said PDX1-positive foregut endoderm cells being multipotent cells that can differentiate into cells, tissues or organs derived from the anterior portion of the gut tube.  
     
     
         2 . The cell culture of  claim 1 , wherein at least about 5% of said human cells are PDX1-positive foregut endoderm cells.  
     
     
         3 . The cell culture of  claim 1 , wherein at least about 10% of said human cells are PDX1-positive foregut endoderm cells.  
     
     
         4 . The cell culture of  claim 1 , wherein at least about 25% of said human cells are PDX1-positive foregut endoderm cells.  
     
     
         5 . The cell culture of  claim 1 , wherein human feeder cells are present in said culture, and wherein at least about 2% of human cells other than said human feeder cells are PDX1-positive foregut endoderm cells.  
     
     
         6 . The cell culture of  claim 1 , wherein said PDX1-positive foregut endoderm cells express the homeobox A13 (HOXA13) gene.  
     
     
         7 . The cell culture of  claim 1 , wherein said PDX1-positive foregut endoderm cells express the homeobox C6 (HOXC6) gene.  
     
     
         8 . The cell culture of  claim 1 , wherein said PDX1-positive foregut endoderm cells express SOX17.  
     
     
         9 . The cell culture of  claim 1 , wherein the expression of PDX1 is greater than the expression of a marker selected from the group consisting of alpha-fetoprotein (AFP), SOX7, SOX1, ZIC1 and NFM in said PDX1-positive foregut endoderm cells.  
     
     
         10 . The cell culture of  claim 1 , wherein said cell culture is substantially free of cells selected from the group consisting of visceral endodermal cells, parietal endodermal cells and neural cells.  
     
     
         11 . The cell culture of  claim 1 , wherein at least about 1 PDX1-positive foregut endoderm cell is present for about every 10 PDX1-negative definitive endoderm cells in said cell culture.  
     
     
         12 . The cell culture of  claim 1 , wherein at least about 1 PDX1-positive foregut endoderm cell is present for about every 5 PDX1-negative definitive endoderm cells in said cell culture.  
     
     
         13 . The cell culture of  claim 1 , wherein at least about 1 PDX1-positive foregut endoderm cell is present for about every 4 PDX1-negative definitive endoderm cells in said cell culture.  
     
     
         14 . The cell culture of  claim 1  further comprising an embryonic stem cell.  
     
     
         15 . The cell culture of  claim 14 , wherein said embryonic stem cell is derived from a tissue selected from the group consisting of the morula, the inner cell mass (ICM) of an embryo and the gonadal ridges of an embryo.  
     
     
         16 . The cell culture of  claim 1  further comprising a retinoid.  
     
     
         17 . The cell culture of  claim 16 , wherein said retinoid is retinoic acid (RA).  
     
     
         18 . The cell culture of  claim 1  further comprising FGF-10.  
     
     
         19 . The cell culture of  claim 1  further comprising B27.  
     
     
         20 . The cell culture of  claim 1  further comprising both RA and FGF-10.  
     
     
         21 . The cell culture of  claim 20  further comprising B27.  
     
     
         22 . A cell population comprising cells wherein at least about 90% of said cells are human PDX1-positive foregut endoderm cells, said PDX1-positive foregut endoderm cells being multipotent cells that can differentiate into cells, tissues or organs derived from the anterior portion of the gut tube.  
     
     
         23 . The cell population of  claim 22 , wherein at least about 95% of said cells are PDX1-positive foregut endoderm cells.  
     
     
         24 . The cell population of  claim 22 , wherein at least about 98% of said cells are PDX1-positive foregut endoderm cells.  
     
     
         25 . The cell population of  claim 22 , wherein said PDX1-positive foregut endoderm cells express the HOXA13 gene.  
     
     
         26 . The cell population of  claim 22 , wherein said PDX1-positive foregut endoderm cells express the HOXC6 gene.  
     
     
         27 . The cell population of  claim 22 , wherein said PDX1-positive foregut endoderm cells express SOX17.  
     
     
         28 . The cell population of  claim 22 , wherein the expression of PDX1 is greater than the expression of a marker selected from the group consisting of AFP, SOX7, SOX1, ZIC1 and NFM in said PDX1-positive foregut endoderm cells.