Site-directed engineering of defined chromosomal sites for recombinant protein and virus expression

In cell line development, the integration of transgenes into the chromosomal DNA of the host cell is a crucial step. Targeted introduction has many advantages over classical random integration procedures because of strong influences of the chromosomal surroundings on the expression of transgenes. Site-directed integration leads to predictable expression properties, avoids screening, is fast, provides high safety, and is thus the method of choice for the targeted integration of transgenes. Recombinase mediated cassette exchange (RMCE) using heterologous recombinases has been described as an efficient and reliable method to target (integrate and replace) transgenes by site-directed engineering of defined chromosomal sites for recombinant protein and virus expression. The article reports on the exploitation of defined chromosomal sites for the consistent production of highly biologically relevant proteins, namely the expression of viral vectors and antibodies. [PUBLICATION ABSTRACT]