Generation of induced pluripotent stem cells without the use of viral vectors

A method for inducing the cardiac differentiation of a population of mammalian cells comprising:

• contacting said mammalian cells with a transducible peptide comprising an ISL1 polypeptide linked to a cell penetration peptide,
• wherein said contacting is for a period of time sufficient to induce said mammalian cells to exhibit at least one characteristic of cardiac differentiation,
• wherein prior to said contacting said mammalian cells did not exhibit at least one characteristic of cardiac differentiation,
• wherein said mammalian cells exhibit at least one characteristic of cardiac differentiation if said mammalian cells:
• a) express at least one marker of cardiac differentiation selected from the group consisting of alpha-myosin heavy chain protein, natriuretic precursor A (ANP), ryanodine receptor, and SERCA,
• b) form sarcomeres in culture,
• c) appear to be visibly beating, or
• d) demonstrate spontaneous membrane depolarization;
• thereby inducing the cardiac differentiation of a population of mammalian cells.

A method for the repair of damaged or diseased cardiac tissue, comprising:

• contacting said damaged or diseased cardiac tissue with a plurality of cells that exhibit at least one characteristic of cardiac differentiation,
• wherein said plurality of cells were induced to exhibit said at least one characteristic of cardiac differentiation by a method comprising:
• contacting said plurality of cells with a transducible peptide comprising an ISL1 polypeptide linked to a cell penetration peptide,
• wherein said plurality of cells exhibits at least one characteristic of cardiac differentiation if the plurality of cells:
• a) expresses at least one marker of cardiac differentiation selected from the group consisting of alpha-myosin heavy chain protein, natriuretic precursor A (ANP), ryanodine receptor, and SERCA;
• forms sarcomeres in culture,
• b) appears visibly to be visibly beating, or
• c) demonstrates spontaneous membrane depolarization;
• wherein said plurality of cells repopulates said damaged or diseased cardiac tissue, thereby repairing said damaged or diseased cardiac tissue.