FIG 2.

(A) Representative MS spectra of glycans identified on research-grade gp120 proteins produced in CHO cells (top) and 293F cells (bottom). The gp120 protein from clade B (strain JR-FL) is shown here as a representative example. Glycan forms corresponding to the most abundant peaks are shown using the standard glycan icons. MS peaks corresponding to oligomannose and complex glycan forms are indicated. (B) Quantitative comparison of relative proportions of various glycan forms (in percent) on CHO- and 293F-derived gp120-B proteins. Glycan structures found at levels greater than 10% of total glycans are highlighted in gray.