Method for the transfer of episomal vectors into animal cells

A method for the transfer of nucleotide sequences and/or exogenous genes into animal cells comprising the following steps in sequence:

• providing an episomal type vector comprising at least one nucleotide sequence and/or gene sequence of interest which must be transferred into, and expressed in the host;
• providing vital male germ cells;
• and
• incubating the vital male germ cells with the episomal vector to allow binding of the episomal vector with the cells and optionally entry of the episomal vector into the nucleus of the vital male germ cells,
• wherein providing vital male germ cells comprises
• selecting sperm cells, having a motility percentage over the total, of at least 70% at the time of harvesting and
• removing seminal fluid from the selected sperm cell to maintain a motility percentage of not less than 65%;
• wherein the removing comprises:
• bringing the selected sperm cells into contact with a suitable wash medium to obtain a first diluted sample
• separating the first diluted sample from the wash medium to obtain a first separated sample;
• bringing the first separated sample into contact with the wash medium to obtain a second diluted sample;
• separating the second diluted sample from the wash medium to obtain a second separated sample;
• wherein the first diluted sample is incubated for 3-10 minutes;
• and
• wherein the wash medium is a composition comprising glucose, at a concentration of between 56 and 69 mM, sodium citrate at a concentration of between 31 and 37 mM, EDTA at a concentration of between 11 and 14 mM, citric acid at a concentration of between 14 and 17 mM and Trizma base at a concentration of between 48 and 59 mM, the final osmolarity typically being between 200 and 320 mOs and the pH being adjusted from 6.6 to 6.8.