Selection strategies for highly productive recombinant cell lines

The limitations of common selection procedures for recombinant cell lines have been investigated. The specific production rate of six closely related recombinant CHO cell lines measured in attached cultures were higher, lower, or similar to that measured in suspension cultures of the same cell line. Likewise the specific production rate measured in static cultures was found to be of restricted use during the selection of recombinant NS0 cell lines. The optimum number of cell lines to select by different criteria has been estimated. Large differences in the productivity of closely related recombinant cell lines even after two rounds of cloning has been observed.