Relationship between Papillomavirus vaccine, vaginal microbiome, and local cytokine response: an exploratory research.

INTRODUCTION: The influence of vaccination on composition of the human microbiome at distinct sites has been recognized as an essential component in the development of new vaccine strategies. The HPV vaccine is widely used to prevent cervical cancer; however, the influence of HPV vaccine on the vaginal microbiota has not been previously investigated. In his study, we performed an initial characterization of the microbiome and cytokine composition in the vagina following administration of the bivalent vaccine against HPV 16/18. MATERIAL AND METHODS: In this exploratory study, fifteen women between 18 and 40 years received three doses of the HPV-16/18 AS04-adjuvanted vaccine (Cervarix®). Cervicovaginal samples were collected before the first dose and 30 days after the third dose. HPV genotyping was performed by the XGEN Flow Chip technique. The cytokines IFN-γ, IL-2, IL-12p70, TNF-α, GM-CSF, IL-4, IL-5, IL-10, and IL-13 were quantitated by multiplex immunoassay. The vaginal microbiome was identified by analysis of the V3/V4 region of the bacterial 16S rRNA gene. RESULTS: The most abundant bacterial species in the vaginal microbiome was Lactobacillus crispatus, followed by L. iners. Bacterial diversity and dominant organisms were unchanged following vaccination. Small decreases in levels of pro and anti-inflammatory cytokines were observed following HPV vaccination, but there was no association between vaginal cytokine levels and microbiome composition. CONCLUSION: Vaginal microbiome is not altered following administration of the standard three-dose HPV-16/18 AS04-adjuvanted (Cervarix®) vaccine.

Synergistic effects of exosomal crocin or curcumin compounds and HPV L1-E7 polypeptide vaccine construct on tumor eradication in C57BL/6 mouse model.

Cervical cancer is the most common malignant tumor in females worldwide. Human papillomavirus (HPV) infection is associated with the occurrence of cervical cancer. Thus, developing an effective and low-cost vaccine against HPV infection, especially in developing countries is an important issue. In this study, a novel HPV L1-E7 fusion multiepitope construct designed by immunoinformatics tools was expressed in bacterial system. HEK-293T cells-derived exosomes were generated and characterized to use as a carrier for crocin and curcumin compounds. The exosomes loaded with crocin and curcumin compounds as a chemotherapeutic agent (ExoCrocin and ExoCurcumin) were used along with the L1-E7 polypeptide for evaluation of immunological and anti-tumor effects in C57BL/6 mouse model. In vitro studies showed that ExoCrocin and ExoCurcumin were not cytotoxic at a certain dose, and they could enter tumor cells. In vivo studies indicated that combination of the L1-E7 polypeptide with ExoCrocin or ExoCurcumin could produce a significant level of immunity directed toward Th1 response and CTL activity. These regimens showed the protective and therapeutic effects against tumor cells (the percentage of tumor-free mice: ~100%). In addition, both ExoCrocin and ExoCurcumin represented similar immunological and anti-tumor effects. Generally, the use of exosomal crocin or curcumin forms along with the L1-E7 polypeptide could significantly induce T-cell immune responses and eradicate tumor cells.

Designing a therapeutic and prophylactic candidate vaccine against human papillomavirus through vaccinomics approaches.

OBJECTIVE: Human papillomavirus (HPV) is the main cause of cervical cancer, the 4th prominent cause of death in women globally. Previous vaccine development projects have led to several approved prophylactic vaccines available commercially, all of which are made using major capsid-based (L1). Administration of minor capsid protein (L2) gave rise to the second generation investigational prophylactic HPV vaccines, none of which are approved yet due to low immunogenicity provided by the L2 capsid protein. On the other hand, post-translation proteins, E6 and E7, have been utilized to develop experimental therapeutic vaccines. Here, in silico designing of a therapeutic and prophylactic vaccine against HPV16 is performed. METHODS: In this study, several immunoinformatic and computational tools were administered to identify and design a vaccine construct with dual prophylactic and therapeutic applications consisting of several epitope regions on L2, E6, and E7 proteins of HPV16. RESULTS: Immunodominant epitope regions (aa 12-23 and 78-78 of L2 protein, aa 11-27 of E6 protein, and aa 70-89 of E7 protein) were employed, which offered adequate immunogenicity to induce immune responses. Resuscitation-promoting factors (RpfB and RpfE) of Mycobacterium tuberculosis were integrated in two separate constructs as TLR4 agonists to act as vaccine adjuvants. Following physiochemical and structural evaluations carried out by various bioinformatics tools, the designed constructs were modeled and validated, resulting in two 3D structures. Molecular docking and molecular dynamic simulations suggested stable ligand-receptor interactions between the designed construct and TLR4. CONCLUSION: Ultimately, this study led to suggest the designed construct as a potential vaccine candidate with both prophylactic and therapeutic applications against HPV by promoting Th1, Th2, CTL, and B cell immune responses, which should be further confirmed in experimental studies.

The Effect of Prophylactic HPV Vaccines on Oral and Oropharyngeal HPV Infection-A Systematic Review.

Human papillomavirus (HPV) imposes an increased risk of developing cervical, anal and oropharyngeal cancer. In the Western world, HPV infection is currently the major cause of oropharyngeal cancer. The effectiveness of HPV vaccines for oral or oropharyngeal HPV infection is yet to be determined. This study conducted a systematic literature search in Pubmed and Embase. Studies investigating the impact of HPV vaccines on oral or oropharyngeal HPV infection were enrolled. This review reports the relative prevention percentage (RPP), including a risk of bias assessment as well as a quality assessment study. Nine studies were included (48,777 participants): five cross-sectional studies; one randomized community trial study (RCT); one longitudinal cohort study; and two case-control studies. A significant mean RPP of 83.9% (66.6-97.8%) was calculated from the cross-sectional studies, 82.4% in the included RCT and 83% in the longitudinal cohort study. Further, two case-control studies that measured antibody response in participants immunized with HPV vaccines were included. Respectively, 100% and 93.2% of participants developed HPV-16 Immunoglobulin G (IgG) antibodies in oral fluids post-vaccination. Analysis of the studies identified a significant decrease in vaccine-type oral or oropharyngeal HPV infections in study participants immunized with HPV vaccines across study designs and heterogenous populations. Further, a significant percentage of participants developed IgG antibodies in oral fluid post-vaccination.

Human Papillomavirus: Screening, Testing, and Prevention.

With more than 200 types identified, human papillomavirus (HPV) commonly causes infections of the skin and mucosa. HPV infection is the most common sexually transmitted infection in the United States. Although most HPV infections are transient and subclinical, some lead to clinical manifestations ranging from benign papillomas or warts to intraepithelial lesions. In some patients, persistent infection with high-risk mucosal types, especially HPV-16 and HPV-18, causes anal, cervical, oropharyngeal, penile, vaginal, and vulvar cancers. Most HPV-related cancers are believed to be caused by sexual spread of the virus. A history of multiple sex partners; initiation of sexual activity at an early age; not using barrier protection; other sexually transmitted infections, including HIV; an immunocompromised state; alcohol use; and smoking have been identified as risk factors for persistent HPV infections. Screening for HPV infection is effective in identifying precancerous lesions and allows for interventions that can prevent the development of cancer. Use of condoms and dental dams may decrease spread of the virus. Vaccination is the primary method of prevention. The nonavalent HPV vaccine is effective in preventing the development of high-grade precancerous cervical lesions in noninfected patients. Vaccination is ideally administered at 11 or 12 years of age, irrespective of the patient's sex. In general, a two-dose series is recommended if administered before 15 years of age; however, individuals who are immunocompromised require three doses.

Effect of Training Pediatric Clinicians in Human Papillomavirus Communication Strategies on Human Papillomavirus Vaccination Rates: A Cluster Randomized Clinical Trial.

Importance: Missed opportunities for human papillomavirus (HPV) vaccination during pediatric health care visits are common. Objectives: To evaluate the effect of online communication training for clinicians on missed opportunities for HPV vaccination rates overall and at well-child care (WCC) visits and visits for acute or chronic illness (hereafter referred to as acute or chronic visits) and on adolescent HPV vaccination rates. Design, Setting, and Participants: From December 26, 2018, to July 30, 2019, a longitudinal cluster randomized clinical trial allocated practices to communication training vs standard of care in staggered 6-month periods. A total of 48 primary care pediatric practices in 19 states were recruited from the American Academy of Pediatrics Pediatric Research in Office Settings network. Participants were clinicians in intervention practices. Outcomes were evaluated for all 11- to 17-year-old adolescents attending 24 intervention practices (188 clinicians) and 24 control practices (177 clinicians). Analyses were as randomized and performed on an intent-to-treat basis, accounting for clustering by practice. Interventions: Three sequential online educational modules were developed to help participating clinicians communicate with parents about the HPV vaccine. Weekly text messages were sent to participating clinicians to reinforce learning. Statisticians were blinded to group assignment. Main Outcomes and Measures: Main outcomes were missed opportunities for HPV vaccination overall and for HPV vaccine initiation and subsequent doses at WCC and acute or chronic visits (visit-level outcome). Secondary outcomes were HPV vaccination rates (person-level outcome). Outcomes were compared during the intervention vs baseline. Results: Altogether, 122 of 188 clinicians in intervention practices participated; of these, 120, 119, and 116 clinicians completed training modules 1, 2, and 3, respectively. During the intervention period, 29 206 adolescents (14 664 girls [50.2%]; mean [SD] age, 14.2 [2.0] years) made 15 888 WCC and 28 123 acute or chronic visits to intervention practices; 33 914 adolescents (17 069 girls [50.3%]; mean [SD] age, 14.2 [2.0] years) made 17 910 WCC and 35 281 acute or chronic visits to control practices. Intervention practices reduced missed opportunities overall by 2.4 percentage points (-2.4%; 95% CI, -3.5% to -1.2%) more than controls. Intervention practices reduced missed opportunities for vaccine initiation during WCC visits by 6.8 percentage points (-6.8%; 95% CI, -9.7% to -3.9%) more than controls. The intervention had no effect on missed opportunities for subsequent doses of the HPV vaccine or at acute or chronic visits. Adolescents in intervention practices had a 3.4-percentage point (95% CI, 0.6%-6.2%) greater improvement in HPV vaccine initiation compared with adolescents in control practices. Conclusions and Relevance: This scalable, online communication training increased HPV vaccination, particularly HPV vaccine initiation at WCC visits. Results support dissemination of this intervention. Trial Registration: ClinicalTrials.gov Identifier: NCT03599557.

Human Papilloma Virus vaccine and prevention of head and neck cancer, what is the current evidence?

OBJECTIVES: Human Papilloma Virus is associated with the development of cancers in the head and neck region. We have witnessed, in the last decades, an increase in number of cases directly related to HPV infection, in particular in the Western Countries. Recently the FDA expanded the indications for Gardasil-9® to include the prevention of head and neck cancer. Objective of this paper is to review the evidence supporting its use. MATERIALS AND METHODS: Bibliographic review enquiring Medline, Web of Science and the Cochrane Library to assess the efficacy of vaccination against oncogenic HPV in the prevention of head and neck squamous cell carcinoma. RESULTS: Two prospective and 4 retrospective studies have evaluated vaccination in prevention of head and neck cancer, using persistent oral infection as surrogate of efficacy. All studies showed lower prevalence of oral infection up to 4 years following vaccination. Vaccine efficacy was estimated between 88 and 93.3%. Because of low vaccine coverage the estimated population-level effect against oral HPV16/18/6/11 infections was only 17.0%. CONCLUSIONS: Antibodies concentration in the oral fluid correlate with serum level, but the threshold to ensure protection is unknown. Duration of protection has not been established. HPV vaccination can provide protection from re-infection (at different mucosal sites) in previously exposed individuals, suggesting possible use of HPV vaccine later in life. Other studies should focus on confirming causal relationship between vaccination and prevention of persistent oral infection and investigate the duration of efficacy, which is crucial in its effectiveness against HNSCC.

Characterization of recombinant gorilla adenovirus HPV therapeutic vaccine PRGN-2009.

There are approximately 44,000 cases of human papillomavirus-associated (HPV-associated) cancer each year in the United States, most commonly caused by HPV types 16 and 18. Prophylactic vaccines successfully prevent healthy people from acquiring HPV infections via HPV-specific antibodies. In order to treat established HPV-associated malignancies, however, new therapies are necessary. Multiple recombinant gorilla adenovirus HPV vaccine constructs were evaluated in NSG-ß2m-/- peripheral blood mononuclear cell-humanized mice bearing SiHa, a human HPV16+ cervical tumor, and/or in the syngeneic HPV16+ TC-1 model. PRGN-2009 is a therapeutic gorilla adenovirus HPV vaccine containing multiple cytotoxic T cell epitopes of the viral oncoproteins HPV 16/18 E6 and E7, including T cell enhancer agonist epitopes. PRGN-2009 treatment reduced tumor volume and increased CD8+ and CD4+ T cells in the tumor microenvironment of humanized mice bearing the human cervical tumor SiHa. PRGN-2009 monotherapy in the syngeneic TC-1 model also reduced tumor volumes and weights, generated high levels of HPV16 E6-specific T cells, and increased multifunctional CD8+ and CD4+ T cells in the tumor microenvironment. These studies provide the first evaluation to our knowledge of a therapeutic gorilla adenovirus HPV vaccine, PRGN-2009, showing promising preclinical antitumor efficacy and induction of HPV-specific T cells, along with the rationale for its evaluation in clinical trials.

The epidemiologic and economic impact of a quadrivalent human papillomavirus vaccine in Thailand.

BACKGROUND: The human papillomavirus (HPV) vaccine was introduced into Thailand's national immunization program in 2017 for 11-12 year old school girls. The objectives of this study were to examine the epidemiological consequences and cost-effectiveness of a routine quadrivalent HPV (4vHPV) vaccination and the routine 4vHPV vaccination plus 5-year catch-up vaccination by comparing with cervical cancer screening only (no vaccination) in Thailand. METHOD: A transmission dynamic model was used to assess the cost-effectiveness of the routine 4vHPV vaccination and the routine 4vHPV vaccination plus catch-up vaccination, compared with no vaccination (screening only) in Thai population. The vaccination coverage rate assumptions were 95% in 11-12-year-old girls for the routine vaccination and 70% in 13-24 year-old females for the 5-year catch-up vaccination. Vaccination costs, direct medical costs of HPV-related diseases, and the number of quality of life years (QALYs) gained were calculated for over a 100-year time horizon with discount rate of 3%. RESULT: The model indicated that the routine 4vHPV vaccination and the routine plus catch-up 4vHPV vaccination strategies could prevent approximately 434,130 and 472,502 cumulative cases of cervical cancer, 182,234 and 199,068 cumulative deaths from cervical cancer and 12,708,349 and 13,641,398 cumulative cases of HPV 6/11 related genital warts, respectively, when compared with no vaccination over 100 years. The estimated cost per QALY gained (ICER) when compared to no vaccination in Thailand was 8,370 THB/QALY for the routine vaccination and 9,650 THB/QALY for the routine with catch-up vaccination strategy. CONCLUSION: Considering the recommended threshold of 160,000 THB/QALY for Thailand, the implementation of the routine 4vHPV vaccination either alone or plus the catch-up vaccination was cost-effective as compared to the cervical cancer screening only.

Two Web-Based and Theory-Based Interventions With and Without Brief Motivational Interviewing in the Promotion of Human Papillomavirus Vaccination Among Chinese Men Who Have Sex With Men: Randomized Controlled Trial.

BACKGROUND: Human papillomavirus (HPV) vaccination is effective in the prevention of vaccine-type genital warts and cancers among men who have sex with men (MSM). OBJECTIVE: The primary objective of this randomized controlled trial (RCT) is to evaluate the efficacies of 2 web- and theory-based interventions with and without brief motivational interviewing (MI) over the phone to increase the completion of HPV vaccination among unvaccinated participants within a 24-month follow-up period compared with the control group. METHODS: A 3-arm parallel-group RCT was conducted between July 2017 and December 2019. Five telephone surveys were conducted at baseline and at 3, 6, 9, and 24 months by blinded interviewers. Participants were Hong Kong Chinese-speaking MSM aged between 18 and 45 years with regular internet access who were recruited from outreaching at venues, web-based recruitment, and peer referral. Those who had ever received HPV vaccination were excluded. A total of 624 participants were randomized into either the online tutorial (OT) only group (n=208), the OT plus MI group (OT-MI; n=208), or the control group (n=208). In total, 459 (459/624, 73.6%) completed the follow-up evaluation at 24 months. Participants in the OT group received a fully automated OT developed based on the health belief model. On top of the same OT, the OT-MI group received brief MI over the phone. Reminders were sent to the participants of the OT and OT-MI groups after 1, 2, 4, 6, and 8 months. Participants in the control group received web-based health communication messages unrelated to HPV or HPV vaccination. The research team validated the self-reported HPV vaccination uptake. Intention-to-treat analysis was used for outcome analyses. Logistic regression models and multivariable linear regression models were used to test the between-group differences in primary and secondary outcomes. Baron and Kenny's methods were used to test the mediation hypothesis. RESULTS: The participants in the OT-MI group reported a significantly higher validated completion of HPV vaccination at 24 months than the control group (36/208, 17.3% vs 15/208, 7.2%; P=.006). However, the difference in HPV vaccination completion between the OT and the control groups (24/208, 11.5% vs 15/208, 7.2%; P=.17), or between OT-MI and OT groups (P=.13), was not statistically significant. The association between randomization status (OT-MI group vs control group) and HPV vaccination completion became statistically nonsignificant after controlling for changes in the perceived susceptibility to HPV (24 months vs baseline), whereas perceived susceptibility remained strongly associated with HPV vaccination uptake in the model (P<.001). Changes in perceived susceptibility fully mediated the intervention effect. CONCLUSIONS: Theory-based OT with brief MI over the phone was effective in increasing HPV vaccination completion among Chinese MSM. Perceived susceptibility is an active theoretical component that causes behavioral changes. TRIAL REGISTRATION: ClinicalTrials.gov NCT03286907; https://clinicaltrials.gov/ct2/show/NCT03286907.

Next generation polyphosphazene immunoadjuvant: Synthesis, self-assembly and in vivo potency with human papillomavirus VLPs-based vaccine.

Poly[di(carboxylatomethylphenoxy)phosphazene] (PCMP), a new member of polyphosphazene immunoadjuvant family, is synthesized. In vitro assessment of a new macromolecule revealed hydrolytic degradation profile and immunostimulatory activity comparable to its clinical stage homologue PCPP; however, PCMP was characterized by a beneficial reduced sensitivity to the ionic environment. In vivo evaluation of PCMP potency was conducted with human papillomavirus (HPV) virus-like particles (VLPs) based RG1-VLPs vaccine. In contrast with previously reported self-assembly of polyphosphazene adjuvants with proteins, which typically results in the formation of complexes with multimeric display of antigens, PCMP surface modified VLPs in a composition dependent pattern, which at a high polymer-to VLPs ratio led to stabilization of antigenic particles. Immunization experiments in mice demonstrated that PCMP adjuvanted RG1-VLPs vaccine induced potent humoral immune responses, in particular, on the level of highly desirable protective cross-neutralizing antibodies, and outperformed PCPP and Alhydrogel adjuvanted formulations.

Anti-pulmonary metastases from cervical cancer responses induced by a human papillomavirus peptide vaccine adjuvanted with CpG-oligodeoxynucleotides in vivo.

Metastasis, particularly hematogenous metastasis, is associated with poor prognosis in patients with cervical cancer. The lungs are the most common site for hematogenous metastasis of cervical cancer. The currently available therapeutic modalities, including surgery, radiotherapy, or chemotherapy do not provide satisfactory clinical outcome for patients with pulmonary metastases. Therefore, it is necessary to investigate an alternative efficacious treatment modality. Therapeutic vaccines may evoke tumor-specific immune responses in patients to attack tumor cells, representing an attractive treatment option for controlling metastatic tumors. Our previous study demonstrated that a single administration of a human papillomavirus 16 E7 peptide vaccine, adjuvanted with unmethylated CpG-oligodeoxynucleotides, induced the clearance of subcutaneous xenograft cervical cancer. In this study, we investigated the anti-metastases responses induced by this vaccine using a murine model of pulmonary metastases from cervical cancer. The results showed that subcutaneous administration of the vaccine inhibited the growth of pulmonary metastases, which may be attributed to the increased infiltration of CD4 + and CD8 + T cells, and decreased number of immunosuppressive cells (including myeloid-derived suppressive cells and tumor-associated macrophages) in the lungs. Meanwhile, the alteration in a panel of cytokines, chemokines, and matrix metalloproteinases induced by the vaccination may contribute to the re-modulation of the local suppressive environment and inhibition of pulmonary metastases. To the best of our knowledge, this is the first report on the efficacy of the vaccine formula against murine pulmonary metastases from cervical cancer.

Broad Neutralization Responses Against Oncogenic Human Papillomaviruses Induced by a Minor Capsid L2 Polytope Genetically Incorporated Into Bacterial Ferritin Nanoparticles.

Cervical cancer remains a global health burden despite the introduction of highly effective vaccines for the prophylaxis of causative human papillomavirus infection (HPV). Current efforts to eradicate cervical cancer focus on the development of broadly protective, cost-effective approaches. HPV minor capsid protein L2 is being recognized as a promising alternative to the major capsid protein L1 because of its ability to induce responses against a wider range of different HPV types. However, a major limitation of L2 as a source of cross-neutralizing epitopes is its lower immunogenicity compared to L1 when assembled into VLPs. Various approaches have been proposed to overcome this limitation, we developed and tested ferritin-based bio-nanoparticles displaying tandemly repeated L2 epitopes from eight different HPV types grafted onto the surface of Pyrococcus furiosus thioredoxin (Pf Trx). Genetic fusion of the Pf Trx-L2(8x) module to P. furiosus ferritin (Pf Fe) did not interfere with ferritin self-assembly into an octahedral structure composed by 24 protomers. In guinea pigs and mice, the ferritin super-scaffolded, L2 antigen induced a broadly neutralizing antibody response covering 14 oncogenic and two non-oncogenic HPV types. Immune-responsiveness lasted for at least one year and the resulting antibodies also conferred protection in a cervico-vaginal mouse model of HPV infection. Given the broad organism distribution of thioredoxin and ferritin, we also verified the lack of cross-reactivity of the antibodies elicited against the scaffolds with human thioredoxin or ferritin. Altogether, the results of this study point to P. furiosus ferritin nanoparticles as a robust platform for the construction of peptide-epitope-based HPV vaccines.

Mobile App Strategy to Facilitate Human Papillomavirus Vaccination Among Young Men Who Have Sex With Men: Pilot Intervention Study.

BACKGROUND: Mobile app-based interventions have been identified as potential facilitators for vaccination among young men who have sex with men (MSM). OBJECTIVE: This pilot study aimed to test the feasibility of a theoretically informed mobile health (mHealth) tool designed to reduce health disparities and facilitate human papillomavirus (HPV) vaccination among a sample of young MSM. METHODS: The development of the mHealth tool was guided by previous research, implementation intention theory, and design thinking. We recruited MSM aged 18-26 years through a popular online dating app and linked participants to our mHealth tool, which provided HPV vaccine information and fostered access to care. RESULTS: A total of 42 young MSM participated in this pilot study in Boston, Massachusetts. Participants reported variable HPV knowledge (ie, high knowledge of HPV risk factors and low knowledge of HPV-related cancer risks for men) and positive vaccine beliefs and attitudes. Of those who were either unvaccinated, not up to date, or did not report vaccine status, 23% (8/35) utilized the mHealth tool to obtain HPV vaccination. Participants primarily utilized the tool's (1) educational components and (2) capabilities facilitating concrete vaccine action plans. CONCLUSIONS: We recruited an underserved at-risk population of youth via an online dating app for our mHealth intervention that resulted in in-person health care delivery. This study was limited by enrollment challenges, including low willingness to download the mHealth tool to mobile devices.

Extending Human Papillomavirus (HPV) vaccination beyond female adolescents and after treatment for high grade CIN: the Italian HPV Study Group (IHSG) review and position paper.

OBJECTIVE: Human PapillomaVirus (HPV) vaccination has been introduced in recent years in clinical practice as the most effective primary prevention strategy for cervical cancer and HPV-induced lesions, either pre-malignant or benign. Since its introduction, HPV vaccination has been progressively demonstrated as extremely effective in preventing extra-genital and male diseases also; furthermore, non only adolescents but adult subjects have been investigated and reported as positively responding to vaccine immunostimulation. More recently, effectiveness of post-treatment vaccine administration has been preliminarily investigated with very promising results in terms of decreased recurrences. On this basis, we report an Italian-focused picture of the state of the art and take a position in favour of the extension of HPV vaccination to male adolescents, to older age groups and to already treated subjects.

Combined prophylactic and therapeutic immune responses against human papillomaviruses induced by a thioredoxin-based L2-E7 nanoparticle vaccine.

Global burden of cervical cancer, the most common cause of mortality caused by human papillomavirus (HPV), is expected to increase during the next decade, mainly because current alternatives for HPV vaccination and cervical cancer screening programs are costly to be established in low-and-middle income countries. Recently, we described the development of the broadly protective, thermostable vaccine antigen Trx-8mer-OVX313 based on the insertion of eight different minor capsid protein L2 neutralization epitopes into a thioredoxin scaffold from the hyperthermophilic archaeon Pyrococcus furiosus and conversion of the resulting antigen into a nanoparticle format (median radius ~9 nm) upon fusion with the heptamerizing OVX313 module. Here we evaluated whether the engineered thioredoxin scaffold, in addition to humoral immune responses, can induce CD8+ T-cell responses upon incorporation of MHC-I-restricted epitopes. By systematically examining the contribution of individual antigen modules, we demonstrated that B-cell and T-cell epitopes can be combined into a single antigen construct without compromising either immunogenicity. While CD8+ T-cell epitopes had no influence on B-cell responses, the L2 polytope (8mer) and OVX313-mediated heptamerization of the final antigen significantly increased CD8+ T-cell responses. In a proof-of-concept experiment, we found that vaccinated mice remained tumor-free even after two consecutive tumor challenges, while unvaccinated mice developed tumors. A cost-effective, broadly protective vaccine with both prophylactic and therapeutic properties represents a promising option to overcome the challenges associated with prevention and treatment of HPV-caused diseases.

Long-term persistence of immune response to the AS04-adjuvanted HPV-16/18 vaccine in Chinese girls aged 9-17 years: Results from an 8-9-year follow-up phase III open-label study.

AIM: In 9-17-year-old Chinese girls, the AS04-adjuvanted HPV-16/18 vaccine (AS04-HPV-16/18) given as three-dose schedule induced high antibody levels, which were noninferior 1 month after the third dose to those observed in 18-25-year-old Chinese women in a large efficacy study. We assessed the persistence of antibodies 8-9 years after vaccination in the same subjects. METHODS: This follow-up phase III, open-label study (NCT03355820) included subjects who had received three doses of AS04-HPV-16/18 in the initial trial (NCT00996125). Serum antibody concentrations were assessed by ELISA and compared to antibody persistence observed in 18-25-year-old Chinese women 6 years after first vaccination in the efficacy study (NCT00779766). RESULTS: Out of the 227 enrolled subjects, 223 were included in the per-protocol immunogenicity analysis. Mean interval from first AS04-HPV-16/18 dose to blood sampling was 101.4 months (8.5 years). For antibodies against HPV-16 and -18, 8.5 years after first vaccine dose all subjects remained seropositive and antibody. Geometric mean concentrations (GMCs) were 1236.3 (95% confidence interval [CI]: 1121.8; 1362.4) and 535.6 (95% CI: 478.6; 599.4) ELISA Units/mL, respectively. These seropositivity rates and antibody GMCs were higher than those observed 6 years after first vaccination of 18-25-year-old women. CONCLUSION: Sustained anti-HPV-16 and -18 immune responses were observed 8-9 years after AS04-HPV-16/18 vaccination of 9-17 year-old Chinese girls that were higher than the ones observed 6 years after first vaccination in Chinese adult women in whom AS04-HPV-16/18 efficacy against cervical intraepithelial neoplasia of grade ≥2 was demonstrated.

Changes in HPV Seroprevalence from an Unvaccinated toward a Girls-Only Vaccinated Population in the Netherlands.

BACKGROUND: In the Netherlands, bivalent human papillomavirus (HPV) vaccination was included in the National Immunization Program for 12-year-old girls in 2010 (vaccination coverage, 45%-60%). We examined possible changes in HPV seroprevalence in the HPV-unvaccinated Dutch population aged 0-89 years, comparing prevaccination data with data of approximately 6 years after implementation of national vaccination. METHODS: Serum samples of men and women were used from two cross-sectional population-based serosurveillance studies performed before (2006-07, n = 6,384) and after (2016-17, n = 5,645) implementation of HPV vaccination in the Netherlands. Seven high-risk HPV-specific antibodies (HPV16, 18, 31, 33, 45, 52, and 58) were tested in a virus-like particle-based multiplex immunoassay. RESULTS: Type-specific HPV seroprevalence increased in women between 2006-07 and 2016-17. Also, a higher seroprevalence for at least one type in women >15 years was found in 2016-17 (31.7%) compared with 2006-07 (25.2%). In men, overall HPV seroprevalence remained similar; however, a lower seroprevalence was found for HPV16 in 2016-17 (7.5%) compared with 2006-07 (10.6%). CONCLUSIONS: Our results indicate an increase in high-risk HPV types in women and a rather stable exposure in men. No clear effects of the strategy of girls-only vaccination were observed in men, probably because of the short time after introduction combined with suboptimal coverage. IMPACT: No herd immunity has been observed yet in a population with suboptimal HPV vaccination coverage.

A therapeutic HPV16 E7 vaccine in combination with active anti-FGF-2 immunization synergistically elicits robust antitumor immunity in mice.

FGF-2 accumulates in many tumor tissues and is closely related to the development of tumor angiogenesis and the immunosuppressive microenvironment. This study aimed to investigate whether active immunization against FGF-2 could modify antitumor immunity and enhance the efficacy of an HPV16 E7-specific therapeutic vaccine. Combined immunization targeting both FGF-2 and E7 significantly suppressed tumor growth, which was accompanied by significantly increased levels of IFN-γ-expressing splenocytes and effector CD8 T cells and decreased levels of immunosuppressive cells such as regulatory T cells (Tregs) and myeloid-derived suppressor cells(MDSCs) in both the spleen and tumor; in addition, the levels of FGF-2 and neovascularization in tumors were decreased in the mice receiving the combined immunization, and tumor cell apoptosis was promoted. The combination of an HPV16 E7-specific vaccine and active immunization against FGF-2 significantly enhances antitumor immune responses in mice with TC-1 tumors, indicating a promising strategy for tumor immunotherapy.

CD40 Accelerates the Antigen-Specific Stem-Like Memory CD8+ T Cells Formation and Human Papilloma Virus (HPV)-Positive Tumor Eradication.

Antigen-specific stem-like memory CD8+ T cells (Tscm) have a series of stem cell characteristics, including long-term survival, self-renewal, anti-apoptosis and persistent differentiation into cytotoxic T cells. The effective induction of tumor-specific CD8+ Tscm could persistently eradicate tumor in pro-tumor hostile microenvironment. This study was to investigate the role of CD40 in HPV16-specific CD8+ Tscm induction and its anti-tumor function. We found that CD40 activation accelerated vaccine-induced HPV16 E7-specific CD8+ Tscm formation. Comparing to other HPV-specific CD8+ T cells, CD8+ Tscm were found to be stronger and long-term anti-tumor function, in vivo and in vitro, even in the adoptive cellular transferring model. Furthermore, high frequencies of Tscm might prevent the HPV infection to move on to the development of cancer. And the CD40 effect on Tscm involved Wnt/ß-catenin activation. Our study suggest that CD40 activation supports the generation of tumor-specific CD8+ Tscm, thus providing new insight into cancer immunotherapy.