Development of cell-based adjuvant and tumor vaccine

• Main Authors: Tzu-Ying Chiang, 江姿瑩
• Other Authors: 林綉茹
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/58356372508694009743

碩士 === 高雄醫學大學 === 醫學遺傳學研究所碩士班 === 94 === we are developing a novel cell adjuvant for naïve targeted-protein immunization. Endogenous Balb/3T3 mouse fibroblast cell was engineered to express mouse membrane IL-2,GM-CSF and IL-18 as cell adjuvents for immunization. We have demonstrated that functional membrane IL-2, GM-CSF and IL-18 can highly express on cell surface to stimulate the proliferation of splenocytes. The endogenous Balb/3T3 cytokines can＇t induce detectable antibody response after immunization. Based on these results, EVI2B, a human type I membrane protein, has been proved as oncogene and overexpression in human colorectal cancer will be as membrane-targeted protein for the development of antibody drug.The EVI2B has been cloned into pLNCX plasmid and successfully expressed on the Balb/3T3 cell surface. pLHCX-EVI2B will be transiently transfected into Balb/3T3, or Balb/3T3-mIL2, mGM-CSF and mIL18, respectively, and then immunized into Balb/c mice to determine the titer of anti-EVI2B antibodies. Our data showed that mIL2 was the best immune stimulator, Balb/3T3-mIL2 EVI2B immunization can produced the highest anti-EVI2B antibody titer. In the future we can use mIL2 as cell based adjuvant to provide a valuable tool for membrane targeted protein immunization. In another way, utilize the characteristic of cytokines which can stimulate immune cells to activate and proliferate, we hope to develop a membrane cytokine tumor vaccine by expressing membrane form IL-18、IL-2 and GM-CSF in tumor to induce synergistic anti-tumor effects. To this aim, we have successfully used retrovirus transduction to stably high express membrane IL-18 、IL-2 、 GM-CSF in CT-26 (murine colorectal carcinoma cells), respectively. We also found that CT-26/mIL-2 tumor vaccine can change tumorgenicity to inhibit the tumor growth in vivo. Importantly, immunization of CT-26/IL-18+GMCSF can induce good memory immunity to prevent the growth of parental CT-26 re-challenge cells. In future, we will estimate the therapeutic efficacy of membrane cytokine tumor vaccine in CT-26 tumor bearing Balb/c mice, positive result will provide a novel method for cancer immunotherapy.