Recombinant glycodelin carrying the same type of glycan structures as contraceptive glycodelin-A can be produced in human kidney 293 cells but not inChinese hamster ovary cells

We have produced human recombinant glycodelin in human kidney 293 cells and in Chinese hamster ovary (CHO) cells. Structural analyses by lectin immuno assays and fast atom bombardment mass spectrometry showed that recombinant human glycodelin produced in CHO cells contains only typical CHO-type glyca ns and is devoid of any of the N,N'-diacetyllactosediamine (lacdiNAc)-based chains previously identified in glycodelin-A (GdA). By contrast, human kid ney 293 cells produced recombinant glycodelin with the same type of carbohy drate structures as GdA. The presence of a beta 1-->4-N-acetylgalactosaminy ltransferase functioning in the synthesis of lacdiNAc-based glycans in huma n kidney 293 cells is concluded to be the cause of the occurrence of lacdiN Ac-based glycans on glycodelin produced in these cells. Furthermore, human kidney 293 cells were found to be particularly suited for the production of recombinant glycodelin when they were cultured in high glucose media. Lowe ring the glucose concentration and the addition of glucosamine resulted in higher relative amounts of oligomannosidic-type glycans and complex glycans with truncated antennae. Human glycodelin is an attractive candidate for t he development of a contraceptive agent, and this study gives valuable info rmation for selecting the proper expression system and cell culture conditi ons for the production of a correctly glycosylated recombinant form.