A cell line may be a permanently established cell culture which will proliferate indefinitely given appropriate fresh medium and space. Cell lines have revolutionized research project and are getting used in vaccine production, testing drug metabolism and cytotoxicity, antibody production, study of gene function, generation of artificial tissues (e.g., artificial skin) and synthesis of biological compounds e.g., therapeutic proteins. Immortalized cell lines are derived from a spread of sources that have chromosomal abnormalities or mutations that let them to repeatedly divide, like tumors. Because immortalized cells continuously divide, they eventually refill the dish or flask during which they're growing. Cells isolated directly from human or tissue using enzymatic or mechanical methods. The adherent cells are usually derived from tissues of organs. Suspension cells don't require attachment for growth and are said to be anchorage-independent cells.