Generation of Affinity-Variant Antibodies via the Alteration of Glycosylation in Light Chain Effected by Defined Culture Conditions of Human Hybridomas

The human hybridoma line HB4C5 produces a lung adenocarcinama specific monoclonal antibody which possesses a N-glycosylated carbohydrate chain on its light chain-hypervariable region. Here we have modified the antigen-binding activity of the antibody by altering glycosylation on the light chain. We examined the effects of varying availability of glucose and other monosaccharides in the culture medium on light chain-glycosylation and antigen binding. In varying glucose-supplemented cultures, the antigen-binding action of the produced antibodies was altered in a dose-dependent manner. When the cell line was cultured in the presence of various kinds of monosaccharides instead of glucose, the produced antibodies again changed their antigen-binding activities. Analysis of the light chains produced under these conditions revealed substantial changes in the light chain-glycosylation. Finally, we demonstrate that appropriate N-glycosylation on the light chain, which lead to higher antigen-binding, can be accomplished by modulating monosaccharide availability in the culture medium.