Conditionally immortalized long-term stem cells and methods of making and using such cells

Abstract

Disclosed are methods for conditionally immortalizing stem cells, including adult and embryonic stem cells, the cells produced by such methods, therapeutic and laboratory or research methods of using such cells, and methods to identify compounds related to cell differentiation and development or to treat diseases, using such cells. A mouse model of acute myeloid leukemia (AML) and cells and methods related to such mouse model are also described.

1 .- 55 . (canceled) 
     
     
         56 . A method for promoting cell proliferation and cell survival of one or more adult stem cells cultured in vitro comprising:
 contacting the one or more adult stem cells in vitro with a fusion protein, wherein the fusion comprises:
 (a) a protein transduction domain of a Tat protein; and 
 (b) a MYC protein that is attached to the protein transduction domain of the Tat protein; and 
   culturing the one or more adult stem cells in a media;   wherein the cell survival and cell proliferation of the one or more adult stem cells is increased as compared with corresponding cells not exposed to the fusion protein.   
     
     
         57 . The method of  claim 56 , wherein the one or more adult stem cells is selected from the group consisting of: hematopoietic stem cells, intestinal stem cells, osteoblastic stem cells, mesenchymal stem cells, neural stem cells, epithelial stem cells, cardiac myocyte progenitor stem cells, skin stem cells, skeletal muscle stem cells, and liver stem cells. 
     
     
         58 . A modified adult stem cell comprising a fusion protein, wherein the fusion comprises:
 (a) a protein transduction domain of a Tat protein; and   (b) a MYC protein that is attached to the protein transduction domain of the Tat protein.   
     
     
         59 . The adult stem cell of  claim 58 , wherein the adult stem cell is selected from among wherein the adult stem cells are selected from the group consisting of: hematopoietic stem cells, intestinal stem cells, osteoblastic stem cells, mesenchymal stem cells, neural stem cells, epithelial stem cells, cardiac myocyte progenitor stem cells, skin stem cells, skeletal muscle stem cells, and liver stem cells.