PRODUCTION OF VALUE-ADDED MILK BY INCORPORATION OF SPECIFIC DNA SEQUENCES INTO MAMMARY EPITHELIAL CELLS

摘要

A method is described to transfer a gene encoding a valuable compound, such as a pharmaceutical, into the secretory cells of the mammary gland to produce a new compound into the milk or to alter the composition of the milk. In this method the packaging cell line producing th e viral-derived particles is infused into the mammary gland. The packaging cells will attach and survive for a period of time within the mammary gland. While the cells are viable, they will supply a continuous source of viral- derived particles to trans-infect the maximum number of mammary epithelial cells. After a period of time in the mammary gland, both the particles and the packaging cells will be destroyed by natural mechanisms while the trans- infected mammary epithelial cells continue to express gene(s) encoding the valuable compound or gene(s) to alter the composition of the milk. One or more genes can be trans-infected including DNA sequences that contribute to the efficie nt production of an active compound or to its stability. The packaging cells and the viral-derived particles used in this method can be those which trans-infect dividing or non-dividing cells and can be used either singly or together. This method can be used alone or in combination with other novel methods designed to ensure that the viral-derived particles are correctly positioned to trans-infect the mammary epithelial cells. Increasing the trans-infection of the mammary epithelial cells with the viral particles wil l result in a higher concentration of the valuable compound in the milk.