title: A conjugate of octamer-binding transcription factor 4 and toll-like receptor 7 agonist prevents the growth and metastasis of testis embryonic carcinoma.
abstract: BACKGROUND
  The immune non-recognition is often the underlying cause of failure in tumor immunotherapeutic. This is because most tumor-related antigens are poorly immunogenic, and fail to arouse an efficient immune response against cancers. Here we synthesized a novel TLR7 agonist, and developed a safe and effective immunotherapeutic vaccine by conjugating this TLR7 agonist with the pluripotency antigen OCT4.
  
  
  METHODS
  Purified recombinant OCT4 protein was covalently linked with a novel TLR7 agonist to form a TLR7-OCT4 conjugate (T7-OCT4). After conjugation, the in vitro release of IL-12 and IFN-γ was observed in spleen lymphocytes. Mice were immunized with TLR7-OCT4, and the release of IFN-γ, the percentages of CD3+/CD8+ T cells and the OCT4-specific cytotoxicity rates were measured. The immunized mice were challenged with mouse embryonic carcinoma (EC), and the tumor volume and tumor weight were determined. Blood routine examination was performed to evaluate the biosafety of TLR7 agonist and TLR7-OCT4 conjugate in mice.
  
  
  RESULTS
  T7-OCT4 conjugate significantly increased the in vitro release of IL-12 and IFN-γ by mouse spleen lymphocytes. In addition, the release of IFN-γ, the percentages of CD3+/CD8+ T cells and the tumor-specific cytotoxicity rates in immunized mice were significantly higher. Importantly, in EC xenografted mice, immunization with T7-OCT4 conjugate decreased the growth of the tumor dramatically up to 90 %, as compared to mice immunized with OCT4 protein or TLR7 agonist alone. Furthermore, blood routine examination demonstrated that no abnormalities of the blood cells and components in the blood fluids were detected by T7-OCT4 and TLR7 agonist injections.
  
  
  CONCLUSIONS
  Our results showed that conjugating OCT4 protein to the novel TLR7 agonist produced a vaccine which is effective and safe in preventing tumor growth in mice. Our results suggest that this type of vaccine formulation has great potentiality in preventive vaccines against OCT4 expressing tumors.
authors.affiliation: The Institute of Urinary and Reproductive, the Engineering Lab of Synthetic Biology, School of Medicine, Shenzhen University, Shenzhen, 518060, China. gmlin@szu.edu.cn.|Shenzhen Key Laboratory of Translational Medicine of Tumor, Cancer Research Center, School of Medicine, Shenzhen University, Shenzhen, 518060, China. gmlin@szu.edu.cn.
authors.forename: Guimiao
authors.initials: G
authors.lastname: Lin
authors.affiliation: The Institute of Urinary and Reproductive, the Engineering Lab of Synthetic Biology, School of Medicine, Shenzhen University, Shenzhen, 518060, China. xmwang@szu.edu.cn.|Shenzhen Key Laboratory of Translational Medicine of Tumor, Cancer Research Center, School of Medicine, Shenzhen University, Shenzhen, 518060, China. xmwang@szu.edu.cn.
authors.forename: Xiaomei
authors.initials: X
authors.lastname: Wang
authors.affiliation: The Institute of Urinary and Reproductive, the Engineering Lab of Synthetic Biology, School of Medicine, Shenzhen University, Shenzhen, 518060, China. 659151341@qq.com.
authors.forename: Wanxian
authors.initials: W
authors.lastname: Yi
authors.affiliation: Shenzhen Key Laboratory of Translational Medicine of Tumor, Cancer Research Center, School of Medicine, Shenzhen University, Shenzhen, 518060, China. zhangchuanxia208@163.com.
authors.forename: Chuanxia
authors.initials: C
authors.lastname: Zhang
authors.affiliation: College of Optoelectronic Engineering, Key Laboratory of Optoelectronics Devices and Systems of Ministry of Education/Guangdong Province, Shenzhen University, Shenzhen, 518060, P. R. China. xugaixia@gmail.com.
authors.forename: Gaixia
authors.initials: G
authors.lastname: Xu
authors.affiliation: College of Optoelectronic Engineering, Key Laboratory of Optoelectronics Devices and Systems of Ministry of Education/Guangdong Province, Shenzhen University, Shenzhen, 518060, P. R. China. 775671378@qq.com.
authors.forename: Xiaomei
authors.initials: X
authors.lastname: Zhu
authors.affiliation: The Institute of Urinary and Reproductive, the Engineering Lab of Synthetic Biology, School of Medicine, Shenzhen University, Shenzhen, 518060, China. caizhiming2000@163.com.
authors.forename: Zhiming
authors.initials: Z
authors.lastname: Cai
authors.affiliation: Shenzhen Key Laboratory of Translational Medicine of Tumor, Cancer Research Center, School of Medicine, Shenzhen University, Shenzhen, 518060, China. 99776271@qq.com.
authors.forename: Yu
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Shenzhen Key Laboratory of Translational Medicine of Tumor, Cancer Research Center, School of Medicine, Shenzhen University, Shenzhen, 518060, China. 61567901@qq.com.
authors.forename: Yuwen
authors.initials: Y
authors.lastname: Diao
authors.affiliation: The Institute of Urinary and Reproductive, the Engineering Lab of Synthetic Biology, School of Medicine, Shenzhen University, Shenzhen, 518060, China. mcmlin@163.com.|Shenzhen Key Laboratory of Translational Medicine of Tumor, Cancer Research Center, School of Medicine, Shenzhen University, Shenzhen, 518060, China. mcmlin@163.com.
authors.forename: Marie Chia-Mi
authors.initials: MC
authors.lastname: Lin
authors.affiliation: The Institute of Urinary and Reproductive, the Engineering Lab of Synthetic Biology, School of Medicine, Shenzhen University, Shenzhen, 518060, China. gyjin@szu.edu.cn.|Shenzhen Key Laboratory of Translational Medicine of Tumor, Cancer Research Center, School of Medicine, Shenzhen University, Shenzhen, 518060, China. gyjin@szu.edu.cn.
authors.forename: Guangyi
authors.initials: G
authors.lastname: Jin
mesh_terms: D000818:Animals; D000951:Antigens, Neoplasm / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000166:cytology; D018236:Carcinoma, Embryonal / Q000378:metabolism* / Q000517:prevention & control; D007371:Interferon-gamma / Q000378:metabolism; D018664:Interleukin-12 / Q000378:metabolism; D008214:Lymphocytes / Q000166:cytology; D008297:Male; D008562:Membrane Glycoproteins / Q000819:agonists / Q000737:chemistry*; D051379:Mice; D008807:Mice, Inbred BALB C; D009362:Neoplasm Metastasis; D009368:Neoplasm Transplantation; D050814:Octamer Transcription Factor-3 / Q000737:chemistry*; D011994:Recombinant Proteins / Q000378:metabolism; D013154:Spleen / Q000378:metabolism; D013602:T-Lymphocytes, Cytotoxic / Q000166:cytology; D013736:Testicular Neoplasms / Q000378:metabolism* / Q000517:prevention & control; D013997:Time Factors; D051199:Toll-Like Receptor 7 / Q000819:agonists / Q000737:chemistry*
chemical_list: D000951:Antigens, Neoplasm; D008562:Membrane Glycoproteins; D050814:Octamer Transcription Factor-3; C494174:Pou5f1 protein, mouse; D011994:Recombinant Proteins; C477038:Tlr7 protein, mouse; D051199:Toll-Like Receptor 7; D018664:Interleukin-12; D007371:Interferon-gamma