Western blot analysis of recombinant IL6.

<p>Analyis of crude leaf extracts from tobacco plants expressing IL6ER either following stable transformation (A) or by transient expression (B). Samples containing 100 µg or 10 µg of total soluble protein (transgenic plants and infiltrarted leaves, respectively) were fractionated by 15% SDS-PAGE under reducing conditions, transferred onto a PVDF membrane, probed with mouse anti-human IL6 and visualized using the ECL-system. C_standard: recombinant human IL6, expressed in <i>E. coli</i>; 9000: control plant transformed with empty binary transformation vector pLH9000 lacking the target gene construct; 66-22: T₁ progeny of a tobacco event transformed with the pLH-IL6ER T-DNA; Ben, Geu, Vir: leaf samples from three different tobacco hosts transfected with the MagnICON vector pICH29912-IL6ER and harvested prior to infiltration (0 dpi) and 10 dpi. (C) Verification of IL6 biological activity using crude leaf extracts from transgenic tobacco compared to a commercial standard IL6 produced in <i>E. coli</i>. Cell growth was measured following exposure to different dilutions of the lead extracts, with the concentration of IL6 determined by ELISA.