Rational design of an EGF-IL18 fusion protein: implication for developing tumor therapeutics.
Interleukin-18 (IL-18) is a proinflammatory cytokine. This protein has a role in regulating immune responses and exhibits significant anti-tumor activities. Epidermal growth factor (EGF) is an important growth factor that plays a central role in the regulation of cell cycle and differentiation. It was proposed that a targeted delivery of IL-18 by generation of IL-18-EGF fusion protein might decrease adverse effects and result in enhancing cytotoxic and antitumor activities. In the present study, a fusion protein, consisting of EGFR binding domain fused to human IL-18 mature peptide via a linker peptide of (Gly(4)Ser) 3, was constructed and expressed in the insect cell line Sf9 using Bac-to-Bac baculovirus expression system. We showed that the purified recombinant fusion protein induced similar levels of IFN-gamma to that of native IL-18 protein in human PBMC in the presence of ConA. Furthermore, EGF receptor competitive test in human epithelial cancer A431 cell line showed that EGF-IL18 fusion protein can specifically bind with EGFR by competing with native EGF protein. These suggest that this rationally designed protein can be further developed as novel tumor therapeutics.
Institute of Cellular and Molecular Medicine, School of Laboratory Medicine, Wenzhou Medical College, Wenzhou, Zhejiang 325035, China.
Jian-Xin
JX
Lu
Ying
Y
Peng
Zhe-Feng
ZF
Meng
Li-Qin
LQ
Jin
Yong-Sui
YS
Lu
Min-Xin
MX
Guan
D000818:Animals; D002294:Carcinoma, Squamous Cell / Q000235:genetics / Q000378:metabolism* / Q000628:therapy; D002460:Cell Line; D016503:Drug Delivery Systems / Q000379:methods*; D015195:Drug Design; D004815:Epidermal Growth Factor / Q000235:genetics / Q000378:metabolism* / Q000627:therapeutic use; D066246:ErbB Receptors / Q000378:metabolism*; D018390:Gene Targeting / Q000379:methods*; D006801:Humans; D020382:Interleukin-18 / Q000235:genetics / Q000378:metabolism* / Q000627:therapeutic use; D015202:Protein Engineering / Q000379:methods*; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D018411:Spodoptera / Q000235:genetics / Q000378:metabolism*; D014162:Transfection / Q000379:methods
D020382:Interleukin-18; D011993:Recombinant Fusion Proteins; D004815:Epidermal Growth Factor; D066246:ErbB Receptors