| Recombinant mammalian glycoproteins are often produced using the baculovirus-insect cell expression vector system. Using this system, cultured insect cells are infected with a recombinant baculovirus that contains the gene of interest under the control of a strong viral promoter. Some benefits of using this system include high levels of foreign gene expression and the ability of insect cells to modify newly synthesized proteins in a eucaryotic fashion. However, N-glycosylation is an important protein processing mechanism, which in insect cells, differs from the pathway found in higher eukaryotes such as mammals. In the following studies, we used molecular genetic techniques to develop novel transgenic insect cell lines with mammalian N-glycosylation processing capabilities. These new insect cell lines constitutively express functional mammalian glycosyltransferases, which extends the endogenous insect cell N-glycan processing machinery. In the most extensively engineered insect cell line, SfSWT1, a recombinant glycoprotein was produced which contained N-glycans that were structurally authentic to mammalian N-glycans. Thus, this new transgenic cell line should be widely useful for the production of more authentic recombinant glycoproteins using the baculovirus-insect cell expression vector system. |
