The use of lectins to select subpopulations of insect cells
Lectins have been used in glycoprotein purification, oligosaccharide analysis, and in cell-selection processes. Here, we utilize lectins in a rational attempt to select a subpopulation of insect cells (Estigmene acrea, EAA) with more complete glycosylation capacity by selecting cells that display more complex-type cell-surface oligosaccharides than the general population of cells. A lectin (ECA) from Erythrina cristagalli, specific for galactose beta(1-4)N-acetylglucosamine, was found to be useful in recognizing a small subpopulation of Sf-21 and EAA cells. Cell selections were performed by lectin affinity chromatography and by selective agglutination. Analysis by lectin blots of cell lysates and a quantitative agglutination assay did not reveal significant differences in regard to the level of complex glycosylation between the negatively and positively selected subpopulations of EAA cells. Statistically significant differences in binding the fluorescently labeled lectin, ECA-TRITC were observed even 30 passages post-selection between EAA subpopulations that were negatively and positively selected by lectin affinity chromatography. There were no differences in the two subpopulations in the ECA quantitative agglutination assay. Thus, the hypothesis that a subpopulation differing in glycosylation capacity exists and that such a subpopulation can be identified by the character of cell-surface oligosaccharides is plausible. However, these differences appear to be too small to be of practical use. Copyright 1999 John Wiley & Sons, Inc.