Methods for reprogramming cells and uses thereof

Abstract

A method of obtaining a pluripotent-like multipotent cell, including providing a cell of a first type which is not a pluripotent-like multipotent cell; contacting the cell of a first type with an agent capable of remodeling the chromatin and/or DNA of the cell; transiently increasing expression of at least one pluripotent gene regulator in the cell of a first type, to a level at which the at least one pluripotent gene regulator is capable of driving transformation of the cell of a first type into the pluripotent-like multipotent cell; and placing or maintaining the cell in a differentiation medium and maintaining intracellular levels of the at least one pluripotent gene regulator for a sufficient period of time to allow a stable pluripotent-like multipotent cell to be obtained; wherein the pluripotent-like multipotent cell so obtained does not exhibit teratoma formation in vivo.

What is claimed is: 
     
         1 . A method of obtaining a pluripotent-like multipotent cell, comprising:
 i) providing a cell of a first type, which is not a pluripotent-like multipotent cell;   ii) contacting the cell of a first type with an agent capable of remodeling the chromatin and/or DNA of the cell, wherein the agent capable of remodeling the chromatin and/or DNA is a histone acetylator, an inhibitor of histone deacetylation, a DNA demethylator, and/or an inhibitor of DNA methylation;   iii) transiently increasing expression of at least one pluripotent gene regulator in the cell of a first type, to a level at which the at least one pluripotent gene regulator is capable of driving transformation of the cell of a first type into the pluripotent-like multipotent cell, wherein the at least one pluripotent gene regulator comprises Oct4, Klf4, Sa114, Nanog, Rex1, Lin28, Sox2, Tpt1, DPPA4 (Stella), DPPA3 or a combination thereof; and   iv) placing or maintaining the cell in a differentiation medium and maintaining intracellular levels of the at least one pluripotent gene regulator for a sufficient period of time to allow a stable pluripotent-like multipotent cell to be obtained;   wherein the pluripotent-like multipotent cell so obtained does not exhibit teratoma formation in vivo.   
     
     
         2 . The method of  claim 1 , wherein, in step (ii), the remodeling agent is methyl-CpG binding domain protein 2 (MBD2), DNA-damage-inducible beta (Gadd45b), valproic acid or 5-azacytidine. 
     
     
         3 . The method of  claim 1 , wherein, in step (ii), the remodeling agent is methyl-CpG binding domain protein 2 (MBD2). 
     
     
         4 . The method of  claim 1 , wherein the pluripotent-like multipotent cell so obtained expresses one or more pluripotent-like cell marker selected from the group consisting of Oct4, Sox2, Nanog, SSEA-4, TRA1-60, TRA1-81 and AP. 
     
     
         5 . The method of  claim 1 , wherein the pluripotent-like multipotent cell so obtained possesses all of the following characteristics:
 (i) can self-renew for significantly longer than a somatic cell;   (ii) is not a cancerous cell;   (iii) is stable and not artificially maintained by forced gene expression and may be maintained in standard cell media;   (v) can differentiate to a unipotent or somatic cell; and   (vi) does not exhibit uncontrolled growth or tumor formation in vivo.   
     
     
         6 . The method of  claim 1 , wherein a plurality of pluripotent-like multipotent cells are obtained and wherein the plurality of pluripotent-like multipotent cells are organized within a three-dimensional structure. 
     
     
         7 . The method of  claim 1 , wherein the cell of the first type is selected from the group consisting of an adipose-derived stem cell, a mesenchymal stem cell, a hematopoietic stem cell, a skin derived precursor cell, a hair follicle cell, a fibroblast, a keratinocyte, an epidermal cell, an endothelial cell, an epithelial cell, a granulosa epithelial cell, a melanocyte, an adipocyte, a chondrocyte, a hepatocyte, a B lymphocyte, a T lymphocyte, a granulocyte, a macrophage, a monocyte, a mononuclear cell, a sertoli cell, a neuron, a glial cell, a cardiac muscle cell, and another muscle cell. 
     
     
         8 . The method of  claim 7 , wherein the cell of the first cell type is a human fibroblast cell, a human keratinocyte, a human adipose derived stem cell, a human mesenchymal stem cell, or a human hematopoietic stem cell. 
     
     
         9 . The method of  claim 1 , further comprising treating the cells of a first cell type with a cytoskeleton disruptor. 
     
     
         10 . The method of  claim 9 , wherein the cytoskeleton disruptor is Cytochalasin B or a myosin inhibitor. 
     
     
         11 . The method of  claim 1 , wherein the pluripotent-like multipotent cell obtained is capable of differentiating into a unipotent or somatic cell. 
     
     
         12 . The method of  claim 1 , wherein in step (iii), the cell of a first type is transfected with at least one expression vector encoding polypeptide(s) selected from the group consisting of: Oct4, Klf4, Sall4, Nanog, Rex1, Lin28, Sox2, Tpt1, DPPA4 (Stella) and DPPA3.