| Abstract: | A recombinant Chinese hamster ovary (CHO) cell clone, S1, stably expressing human insulin-like growth factor binding protein-1
(hIGFBP-1), was treated with polyethylene glycol (PEG), resulting in cell fusion, in order to further enhance the protein
expression by increasing the gene copy number and/or the amount of organelles important to the protein expression/-secretion.
Both the fused cell line, Peg1, and its mother cell line, S1, were adapted to serum-free growth in suspension and were characterised
with respect to growth and productivity. Peg1 was easier to adapt to the serum-free suspension conditions and had a higher
viability during the adaptation period than S1. Furthermore, Peg1 showed a stable productivity of hIGFBP-1 that was twice
as high as that for S1 under both adherent and suspension conditions. A considerable difference in the specific productivity
(up to 3–4 times) was noticed during the growth phase. PEG fusion experiments have earlier been studied in our laboratory
with CHO cells producing recombinant factor VIII and our results correlates very well with the results obtained with the factor
VIII producing cells. Surprisingly, it was possible to obtain high producing recombinant cell lines, which were stable for
more than 4 months.
This revised version was published online in July 2006 with corrections to the Cover Date. |
