title: Oral vaccination with recombinant Listeria monocytogenes expressing human papillomavirus type 16 E7 can cause tumor growth in mice to regress.
abstract: Listeria monocytogenes is a Gram-positive, facultative intracellular bacterium with the ability to present secreted proteins to the major histocompatibility complex class I pathway to stimulate cell-mediated immune response. In our study, we constructed the recombinant L. monocytogenes encoding human papillomavirus type 16 E7 gene (rLM-E7). When orally administered to syngeneic mice, rLM-E7 could induce a cytotoxic T-lymphocyte (CTL) response. Furthermore, in vitro flow cytometric assay and in vivo immune deficiency assays showed that rLM-E7 could prevent and eradicate tumor growth via CD8+-dependent CTLs. Hence, the potency of rLM-E7 as a therapeutic vaccine for cervical cancer is the result of the induction E7-specific cell-mediated immunity by L. monocytogenes. In addition to potency, this vaccine also offers ease of administration and reduced cost of production compared with other vaccines formulated for injection. Thus, L. monocytogenes encoding HPV-16 E7 may be a useful oral vaccine for cervical cancer treatment.
authors.affiliation: Department of Microbiology & Immunology, National Defense Medical Center, Taipei, Taiwan, Republic of China.
authors.forename: Chih-Wei
authors.initials: CW
authors.lastname: Lin
authors.forename: Jen-Yi
authors.initials: JY
authors.lastname: Lee
authors.forename: Yeou-Ping
authors.initials: YP
authors.lastname: Tsao
authors.forename: Che-Piao
authors.initials: CP
authors.lastname: Shen
authors.forename: Hung-Cheng
authors.initials: HC
authors.lastname: Lai
authors.forename: Show-Li
authors.initials: SL
authors.lastname: Chen
mesh_terms: D000284:Administration, Oral; D000595:Amino Acid Sequence; D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D019496:Cancer Vaccines / Q000276:immunology*; D005260:Female; D008089:Listeria monocytogenes / Q000235:genetics*; D051379:Mice; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D009374:Neoplasms, Experimental / Q000473:pathology / Q000628:therapy*; D009856:Oncogene Proteins, Viral / Q000096:biosynthesis / Q000276:immunology*; D050725:Papillomavirus E7 Proteins; D011994:Recombinant Proteins / Q000276:immunology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D002583:Uterine Cervical Neoplasms / Q000628:therapy; D014611:Vaccination; D014614:Vaccines, Synthetic / Q000276:immunology*
chemical_list: D019496:Cancer Vaccines; D009856:Oncogene Proteins, Viral; D050725:Papillomavirus E7 Proteins; D011994:Recombinant Proteins; D014614:Vaccines, Synthetic; C059731:oncogene protein E7, Human papillomavirus type 16