Methods for the in vitro manufacture of gastric fundus tissue and compositions related to same

Abstract

The instant disclosure relates to methods for converting mammalian definitive endoderm (DE) cells into specific tissue(s) or organ(s) through directed differentiation. In particular, the disclosure relates to formation of gastric fundus tissue and/or organoids formed from differentiated definitive endoderm.

1 .- 18 . (canceled) 
     
     
         19 . A human fundal gastric organoid (hFGO) characterized by:
 a) MUC5AC-positive surface mucous cells and MUC6-positive mucous neck cells;   b) endocrine cells expressing ghrelin (GHRL), somatostatin (SST), and histamine;   c) chief cells expressing MIST1, pepsinogen A (PGA5), and pepsinogen C (PGC);   d) parietal cell-dense glands;   e) parietal cells expressing ATP4A, ATP4B, and GIF; and   f) wherein the hFGO exhibits a greater number of parietal cells and elevated expression of ATP4A, ATP4B, and GIF relative to an hFGO that has not been treated with a MEK inhibitor.   
     
     
         20 . The hFGO of  claim 19 , wherein the hFGO comprises a lumen and is characterized by a decrease in the pH of the lumen when treated with histamine, and an inhibition of this decrease when pre-treated with famotidine or omeprazole. 
     
     
         21 . The hFGO of  claim 19 , wherein the hFGO has been treated with a MEK inhibitor. 
     
     
         22 . The hFGO of  claim 19 , wherein the MEK inhibitor is PD0325901. 
     
     
         23 . The hFGO of  claim 21 , wherein the MEK inhibitor is PD0325901. 
     
     
         24 . The hFGO of  claim 21 , wherein the hFGO has been treated with the MEK inhibitor for two days±24 hours. 
     
     
         25 . The hFGO of  claim 19 , wherein the hFGO that has not been treated with a MEK inhibitor also has not been treated with BMP4. 
     
     
         26 . The hFGO of  claim 21 , wherein the hFGO has been further treated with BMP4. 
     
     
         27 . The hFGO of  claim 19 , wherein the hFGO is derived from definitive endoderm. 
     
     
         28 . The hFGO of  claim 27 , wherein the definitive endoderm is derived from a pluripotent stem cell.