S4 Fig -

Purified recombinant immunoglobulin IgG2aκ from NRC-2410 (A), NRC-2894 (B), NRC-13810 (C), and NRC-49680 (D). Cellular supernatants of the recombinant antibodies were collected and incubated with protein A beads overnight at 4°C with mixing. The Ig-bound beads were then gently spun down at low speed and packed into a column. The column was washed with 5 column volumes (CVs) of binding buffer prior to stepwise acid washes (2 CVs in each pH buffer) followed by acid elution (E1-9 fractions). The presence of Ig heavy and light chains was examined by A280 and gel electrophoresis followed by immunoblot against a polyclonal anti-mouse IgG antibody (top gel). The remaining proteins left on the transferred gels were stained by Coomassie or Silver staining to confirm Ig presence (bottom gel). (TIF)