Western blotting analysis of the IL6 expression with reduced IPTG concentrations.

(S) soluble and (I) insoluble fraction of IL6, expressed with either 1 mM or 0.1 mM IPTG at 22°C in the cytoplasm of the E. coli BL21 strain with and without the concomitant overexpression of endogenous cytoplasmic chaperones or in fusion to GST.