title: Construction and expression of novel immunotoxin cpIL-4(13D)-PE38KDEL with increased activity.
abstract: Interleukin-4 receptors (IL-4Rs) are expressed on a wide variety of human cancer cells, and therefore it may be a good option to treat IL-4R-bearing tumors with IL-4-fusing immunotoxins. In this study, the gene encoding human interleukin-4 mutein cpIL-4(13D) was obtained through overlapping polymerase chain reaction. A chimeric immunotoxin was constructed by genetically fusing the mutein cpIL-4(13D) to a modified version of Pseudomonas exotoxin A (PE38KDEL) and was expressed in Escherichia coli AD494 (DE3). The expression level of the fusion protein was about 30% of the total bacterial protein assessed by SDS-PAGE analysis. After purification by affinity chromatography and anion exchange chromatography, the chimeric protein was tested for its cytotoxicity. Our data show that cpIL-4(13D)-PE38KDEL has improved cytotoxicity on IL-4R-bearing tumor cells in comparison with other IL-4-fusing immunotoxins and might be useful in treating tumors with a large number of IL-4Rs.
authors.affiliation: Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang City, Liaoning Province 110016, P. R. China. cjxlib@hotmail.com
authors.forename: J-X
authors.initials: JX
authors.lastname: Cui
authors.forename: J-F
authors.initials: JF
authors.lastname: Ji
authors.forename: A-G
authors.initials: AG
authors.lastname: Lv
authors.forename: W-F
authors.initials: WF
authors.lastname: Wu
mesh_terms: D000818:Animals; D001483:Base Sequence; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D004354:Drug Screening Assays, Antitumor; D004926:Escherichia coli / Q000235:genetics; D005822:Genetic Vectors; D005909:Glioblastoma / Q000473:pathology; D006801:Humans; D018796:Immunoconjugates; D000922:Immunotoxins / Q000737:chemistry* / Q000494:pharmacology*; D007739:L Cells; D051379:Mice; D008969:Molecular Sequence Data; D019948:Receptors, Interleukin-4 / Q000737:chemistry* / Q000502:physiology; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000737:chemistry* / Q000494:pharmacology*
chemical_list: D018796:Immunoconjugates; D000922:Immunotoxins; D019948:Receptors, Interleukin-4; D011993:Recombinant Fusion Proteins; C501872:cpIL-4(13D)-PE38KDEL immunotoxin