Supplementary Figure 3: Purification of recombinant gp120s.

Recombinant gp120s produced by transient transfection of non-adherent CHO-s cells were captured over a GNA lectin column and eluted with tris-glycine pH 3. Eluents were subjected to preparative size–exclusion over a superdex 200 10/60 column. Following concentration proteins were extracted twice with triton-X114 to remove trace endotoxin. Analytic size exclusion using a superdex 200 10/40 column (flow –rate 0.5 ml/min) was used to verify the purity of each preparation, which typically exceed 90%. A representative preparation of the pre- and post-size exclusion protein is shown.