title: Toll-like receptor agonist imiquimod facilitates antigen-specific CD8+ T-cell accumulation in the genital tract leading to tumor control through IFNγ.
abstract: OBJECTIVE
  Imiquimod is a Toll-like receptor 7 agonist used topically to treat external genital warts and basal cell carcinoma. We examined the combination of topical imiquimod with intramuscular administration of CRT/E7, a therapeutic human papillomavirus (HPV) vaccine comprised of a naked DNA vector expressing calreticulin fused to HPV16 E7.
  
  
  METHODS
  Using an orthotopic HPV16 E6/E7(+) syngeneic tumor, TC-1, as a model of high-grade cervical/vaginal/vulvar intraepithelial neoplasia, we assessed if combining CRT/E7 vaccination with cervicovaginal deposition of imiquimod could result in synergistic activities promoting immune-mediated tumor clearance.
  
  
  RESULTS
  Imiquimod induced cervicovaginal accumulation of activated E7-specific CD8(+) T cells elicited by CRT/E7 vaccination. Recruitment was not dependent upon the specificity of the activated CD8(+) T cells, but was significantly reduced in mice lacking the IFNγ receptor. Intravaginal imiquimod deposition induced upregulation of CXCL9 and CXCL10 mRNA expression in the genital tract, which are produced in response to IFNγ receptor signaling and attract cells expressing their ligand, CXCR3. The T cells attracted by imiquimod to the cervicovaginal tract expressed CXCR3 as well as CD49a, an integrin involved in homing and retention of CD8(+) T cells at mucosal sites. Our results indicate that intramuscular CRT/E7 vaccination in conjunction with intravaginal imiquimod deposition recruits antigen-specific CXCR3(+) CD8(+) T cells to the genital tract.
  
  
  CONCLUSIONS
  Several therapeutic HPV vaccination clinical trials using a spectrum of DNA vaccines, including vaccination in concert with cervical imiquimod, are ongoing. Our study identifies a mechanism by which these strategies could provide therapeutic benefit. Our findings support accumulating evidence that manipulation of the tumor microenvironment can enhance the therapeutic efficacy of strategies that induce tumor-specific T cells.
authors.affiliation: Department of Pathology, Johns Hopkins Medical Institutions, Baltimore, Maryland. Department of General Surgery, Chang Gung Memorial Hospital at Keelung, Keelung City, Taiwan. College of Medicine, Chang Gung University, Taoyuan, Taiwan.
authors.forename: Ruey-Shyang
authors.initials: RS
authors.lastname: Soong
authors.affiliation: Department of Pathology, Johns Hopkins Medical Institutions, Baltimore, Maryland. School of Pharmacy, Fudan University, Shanghai, China. Department of Pharmacology and Toxicology, Shanghai Institute of Planned Parenthood Research, Shanghai, China. Department of Obstetrics and Gynecology, Shanghai Tenth People's Hospital of Tongji University, Shanghai, China.
authors.forename: Liwen
authors.initials: L
authors.lastname: Song
authors.affiliation: Johns Hopkins University, Baltimore, Maryland.
authors.forename: Janson
authors.initials: J
authors.lastname: Trieu
authors.affiliation: Department of Pathology, Johns Hopkins Medical Institutions, Baltimore, Maryland.
authors.forename: Jayne
authors.initials: J
authors.lastname: Knoff
authors.affiliation: Department of Pathology, Johns Hopkins Medical Institutions, Baltimore, Maryland.
authors.forename: Liangmei
authors.initials: L
authors.lastname: He
authors.affiliation: Department of Pathology, Johns Hopkins Medical Institutions, Baltimore, Maryland.
authors.forename: Ya-Chea
authors.initials: YC
authors.lastname: Tsai
authors.affiliation: Department of Obstetrics and Gynecology, University of Alabama at Birmingham, Birmingham, Alabama.
authors.forename: Warner
authors.initials: W
authors.lastname: Huh
authors.affiliation: Papivax LLC, Severna Park, Maryland.
authors.forename: Yung-Nien
authors.initials: YN
authors.lastname: Chang
authors.affiliation: Department of Obstetrics and Gynecology, National Taiwan University College of Medicine, Taipei, Taiwan.
authors.forename: Wen-Fang
authors.initials: WF
authors.lastname: Cheng
authors.affiliation: Department of Pathology, Johns Hopkins Medical Institutions, Baltimore, Maryland. Department of Obstetrics and Gynecology, Johns Hopkins Medical Institutions, Baltimore, Maryland. Department of Oncology, Johns Hopkins Medical Institutions, Baltimore, Maryland.
authors.forename: Richard B S
authors.initials: RB
authors.lastname: Roden
authors.affiliation: Department of Pathology, Johns Hopkins Medical Institutions, Baltimore, Maryland. Department of Obstetrics and Gynecology, Johns Hopkins Medical Institutions, Baltimore, Maryland. Department of Oncology, Johns Hopkins Medical Institutions, Baltimore, Maryland. Department of Molecular Microbiology and Immunology, Johns Hopkins Medical Institutions, Baltimore, Maryland. chung2@jhmi.edu wutc@jhmi.edu.
authors.forename: T-C
authors.initials: TC
authors.lastname: Wu
authors.affiliation: Department of Pathology, Johns Hopkins Medical Institutions, Baltimore, Maryland. Department of Obstetrics and Gynecology, Johns Hopkins Medical Institutions, Baltimore, Maryland. Department of Oncology, Johns Hopkins Medical Institutions, Baltimore, Maryland.
authors.forename: Cornelia L
authors.initials: CL
authors.lastname: Trimble
authors.affiliation: Department of Pathology, Johns Hopkins Medical Institutions, Baltimore, Maryland. Department of Oncology, Johns Hopkins Medical Institutions, Baltimore, Maryland. chung2@jhmi.edu wutc@jhmi.edu.
authors.forename: Chien-Fu
authors.initials: CF
authors.lastname: Hung
mesh_terms: D000634:Aminoquinolines / Q000494:pharmacology*; D000818:Animals; D000941:Antigens / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000187:drug effects* / Q000276:immunology*; D005260:Female; D005835:Genitalia / Q000187:drug effects* / Q000821:virology; D000077271:Imiquimod; D039423:Integrin alpha1 / Q000276:immunology; D007371:Interferon-gamma / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D009369:Neoplasms / Q000188:drug therapy / Q000276:immunology / Q000821:virology; D009856:Oncogene Proteins, Viral / Q000276:immunology; D050725:Papillomavirus E7 Proteins / Q000276:immunology; D053918:Papillomavirus Vaccines / Q000276:immunology; D017471:Receptors, Interferon / Q000276:immunology; D012097:Repressor Proteins / Q000276:immunology; D051193:Toll-Like Receptors / Q000819:agonists*; D014611:Vaccination / Q000379:methods; D019444:Vaccines, DNA / Q000276:immunology; D000096743:Interferon gamma Receptor
chemical_list: D000634:Aminoquinolines; D000941:Antigens; D000077271:Imiquimod; D039423:Integrin alpha1; D007371:Interferon-gamma; D009856:Oncogene Proteins, Viral; D050725:Papillomavirus E7 Proteins; D053918:Papillomavirus Vaccines; D017471:Receptors, Interferon; D012097:Repressor Proteins; D051193:Toll-Like Receptors; D019444:Vaccines, DNA; D000096743:Interferon gamma Receptor; C068651:E6 protein, Human papillomavirus type 16; C059731:oncogene protein E7, Human papillomavirus type 16