Circular nucleic acid vectors, and methods for making and using the same

A method for introducing an expression cassette into a target cell, said method comprising:

• introducing into said target cell a circular vector that is devoid of bacterial transcriptional silencing sequences, wherein said circular vector comprises said expression cassette and provides for persistent and high level expression of said expression cassette when present in a cell.

A method for introducing an expression cassette into a target cell of a vascularized multi-cellular organism in a manner such that the encoded protein of said expression cassette is persistently expressed in said target cell at a high level, said method comprising:

• systemically administering to said vascularized multi-cellular organism a circular vector that is devoid of bacterial transcriptional silencing sequences, wherein said circular vector comprises said expression cassette and provides for persistent and high level expression of said expression cassette when present in said target cell;
• to persistently express said expression cassette encoded protein at a high level in said target cell.

A method of persistently expressing a protein at a high level in a hepatic target cell of a mammal, said method comprising:

• intravenously administering to said mammal an aqueous formulation of a circular vector that is devoid of bacterial transcriptional silencing sequences, wherein said circular vector comprises said expression cassette and provides for persistent and high level expression of said expression cassette when present in a cell;
• to persistently express said protein at a high level in said hepatic target cell.

(canceled)

A method for preparing a circular nucleic acid vector comprising an expression cassette, said method comprising:

• contacting a parent nucleic acid comprising said expression cassette flanked by attB and attP sites recognized by a unidirectional site-specific recombinase with said unidirectional site-specific recombinase under conditions sufficient to produce said circular nucleic acid vector comprising said expression cassette.

35-52. (canceled)