Fig. 1

Identification of IL-35 Expression in E. coli/IL-35 in vitro and vivo. a Single-colony PCR analysis of recombinant E. coli/IL-35. Lane M DNA marker DL2000; lane 1 negative control; lanes 2 singlecolony PCR products of recombinant pET28a(+)-IL-35. b Double-enzyme digestion of recombinant plasmid. Lane M DNA marker DL2000; lane 1 non-enzyme digestion of recombinant plasmid; lane 2 double-enzyme digestion products of recombinant plasmid. c Tricine-SDS-PAGE of the protein expressions in E. coli/IL-35 In lane 1, the strains are transformations of pET28a(+)/IL-35; lane 2 is the empty vector strain. The arrow indicates the dark bands corresponding to the expressed IL-35 protein on Tricine-SDS-PAGE. d Western blot analysis of the cell lysate proteins from the lL-35 producer strain E. coli/IL-35 (lane 1) and empty vector strain E. coli/0 (lane 2). E. coli/IL-35 increased IL-12a and EBI3 mRNA expression in colon tissues (e) and the serum concentration of IL-35 (f) in DSS-induced colitis mice, n = 10 mice per group. Compared with the DSS group, *p < 0.05; compared with the DSS + E. coli/0 group, *p < 0.05