Methods for reprogramming cells

A method for reprogramming a human somatic cell to a cell exhibiting at least one characteristic of a human trophoblast stem cell (TSC), the method comprising the following steps in order:

• a) increasing the protein expression or amount of one or more factors in the somatic cell, wherein the factors are for reprogramming the cell towards a de-differentiated or pluripotent state;
• b) culturing the cell for a sufficient time and under conditions to allow the reprogramming of the cell towards a de-differentiated or pluripotent state;
• c) contacting the cell with a TSC culture medium suitable for sustaining trophoblast stem cells (TSC), wherein the cell is contacted with the TSC medium during the reprogramming process, and prior to completion of reprogramming of the cell to a pluripotent state;
• and
• d) culturing the cell in the TSC medium for a sufficient time and under conditions to allow the cell to exhibit at least one characteristic of a TSC,
• thereby reprogramming the somatic cell to a cell exhibiting at least one characteristic of a TSC, wherein the protein expression, or amount, of the factor(s) for reprogramming a somatic cell towards a de-differentiated or pluripotent state, is/are increased by:
• contacting the cell with an agent which increases the expression of the factor, wherein the agent is selected from the group consisting of:
• a nucleotide sequence, a protein, an aptamer and small molecule, ribosome, RNAi agent and peptide-nucleic acid (PNA) and analogues or variants thereof;
• or
• introducing at least one nucleic acid comprising a nucleotide sequence encoding the factor, or encoding a functional fragment thereof, in the cell;
• and
• wherein the at least one characteristic of a TSC comprises one or more of:
• an undifferentiated, bipotential state;
• cobblestone-shaped colony appearance;
• the ability to differentiate into a cell exhibiting one or more characteristics of an extravillous trophoblast (EVT) or syncytiotrophoblast (ST);
• a methylation pattern similar to a blastocyst-derived TSC, as determined by a bisulfite assay;
• and
• the expression of one or more biochemical markers of a TSC, as determined by an immunohistochemistry and/or PCR assay.