Figure 3.

Effect of pH and proteinase inhibitors on in vitro processing of 2F5. (A) CHO-derived 2F5 (200 ng) was incubated with intercellular fluid (130 ng protein) for 16 h at the indicated pH and then analyzed by immunoblotting with antibodies to the heavy chain of human IgG. (B) CHO-derived 2F5 (200 ng) was incubated with intercellular fluid (IF; 650 ng protein) or total soluble leaf extracts (EX; 200 ng protein) for 16 h in the absence (control) or presence of the indicated proteinase inhibitors (10 μM: leupeptin, E-64, pepstatin; 2 mM: PMSF, phenanthroline) and then analyzed as above. PIC, proteinase inhibitor cocktail. The migration positions of selected molecular mass standards are indicated, with their respective masses expressed in kDa. The results shown are representative of at least two independent experiments.