Gene gun administration of therapeutic HPV DNA vaccination restores the efficacy of prolonged defrosted viral based vaccine.
Freshly defrosted vaccines generate promising antitumor immunity by raising both robust CD8 and CD4 responses with a TC1/Th1-dominant cytokine profile. However, prolonged (overnight) defrosted Sindbis virus-E7/HSP70 priming and Vaccinia-E7/HSP70 booster in mouse model only elicited 20% long-term tumor-free survival in comparison with the fresh vaccines. The present study is to search the possible cause of its potency loss, and to evaluate the ability of pcDNA-E7/HSP70 DNA vaccination via gene gun in restoring the efficacy of E7-specific immune responses and antitumor properties. We used prolonged defrosted SINrep5-E7/HSP70 prime and defrosted Vac-E7/HSP70 boost subcutaneously, and administered intradermally cluster (3-day interval) gene gun plasmid E7-HSP70DNA vaccine twice, and evaluated its ability to generate antigen-specific cytotoxic CD8+ T-cell responses using flow cytometry as well as antitumor responses using animal positron-emission tomography (PET) imaging. The prolonged defrosted vaccines showed a significant reduction in the infectivity and a significant decrease of CD8+ and CD4+ T-cells immune responses. Administration of cluster gene gun plasmid E7-HSP70DNA twice was also found to lead to restoration of immunity that elicits a full recovery of the antitumor efficacy of the prolonged defrosted vaccines. Our study suggested that adding cluster gene gun plasmid E7-HSP70DNA vaccine twice offered a simple solution in restoring the efficacy of the prime-boost vaccination with viral vectors and has potentially significant clinical applications.
Department of Obstetrics and Gynecology, Chang Gung Memorial Hospital Linkou Medical Center, 5, Fu-Shin Street, Kweishan, Taoyuan, Taiwan. 51424@cgmh.org.tw
Cheng-Tao
CT
Lin
Chih-Feng
CF
Yen
Sheng-Wen
SW
Shaw
Tzu-Chen
TC
Yen
Yin-Ju
YJ
Chen
Yung-Kuei
YK
Soong
Chyong-Huey
CH
Lai
D000818:Animals; D019470:Biolistics; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D019496:Cancer Vaccines / Q000276:immunology*; D045744:Cell Line, Tumor; D015925:Cryopreservation; D005260:Female; D018840:HSP70 Heat-Shock Proteins / Q000276:immunology; D007111:Immunity, Cellular; D007117:Immunization, Secondary; D007371:Interferon-gamma / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D050725:Papillomavirus E7 Proteins / Q000276:immunology*; D053918:Papillomavirus Vaccines / Q000276:immunology*; D049268:Positron-Emission Tomography; D002583:Uterine Cervical Neoplasms / Q000517:prevention & control*; D019444:Vaccines, DNA / Q000276:immunology
D019496:Cancer Vaccines; D018840:HSP70 Heat-Shock Proteins; D050725:Papillomavirus E7 Proteins; D053918:Papillomavirus Vaccines; D019444:Vaccines, DNA; D007371:Interferon-gamma