Therapeutic HPV Vaccines Research Articles

999MO HARE-40: A phase I/II trial of therapeutic HPV vaccine (BNT113) in patients with HPV16 driven carcinoma

999MO HARE-40: A phase I/II trial of therapeutic HPV vaccine (BNT113) in patients with HPV16 driven carcinoma

Lipid Nanoparticles Outperform Electroporation in Delivering Therapeutic HPV DNA Vaccines.

Therapeutic HPV vaccines that induce potent HPV-specific cellular immunity and eliminate pre-existing infections remain elusive. Among various candidates under development, those based on DNA constructs are considered promising because of their safety profile, stability, and efficacy. However, the use of electroporation (EP) as a main delivery method for such vaccines is notorious for adverse effects like pain and potentially irreversible muscle damage. Moreover, the requirement for specialized equipment adds to the complexity and cost of clinical applications. As an alternative to EP, lipid nanoparticles (LNPs) that are already commercially available for delivering mRNA and siRNA vaccines are likely to be feasible. Here, we have compared three intramuscular delivery systems in a preclinical setting. In terms of HPV-specific cellular immune responses, mice receiving therapeutic HPV DNA vaccines encapsulated with LNP demonstrated superior outcomes when compared to EP administration, while the naked plasmid vaccine showed negligible responses, as expected. In addition, SM-102 LNP M exhibited the most promising results in delivering candidate DNA vaccines. Thus, LNP proves to be a feasible delivery method in vivo, offering improved immunogenicity over traditional approaches.

Therapeutic HPV Vaccination: A Strategy for Cervical Cancer Elimination in India

Therapeutic HPV Vaccination: A Strategy for Cervical Cancer Elimination in India

New Perspectives in Therapeutic Vaccines for HPV: A Critical Review.

Human Papillomavirus is the main cause of cervical cancer, including squamous cell carcinoma of the oropharynx, anus, rectum, penis, vagina, and vulva. In recent years, considerable effort has been made to control HPV-induced diseases using either prophylactic or therapeutic approaches. A critical review of the literature about the therapeutic Human Papillomavirus vaccine was performed to analyze its efficacy in the treatment of female lower genital tract lesions and its possible perspective application in clinical practice. The most important medical databases were consulted, and all papers published from 2000 until 2021 were considered. We retrieved a group of seven papers, reporting the role of anti HPV therapeutic vaccines against the L2 protein in the order of their efficacy and safety in female lower genital tract disease. In addition, the immune response due to vaccine administration was evaluated. The development of therapeutic vaccines represents an interesting challenge for the treatment of HPV infection of the lower genital tract. Literature data underline that the L2 protein may be an interesting and promising target in the development of therapeutic HPV vaccines, but the possible strengths and the unclear longevity of L2 immune responses are factors to be considered before clinical use.

Importance of the Immune Microenvironment in the Spontaneous Regression of Cervical Squamous Intraepithelial Lesions (cSIL) and Implications for Immunotherapy.

Cervical high-grade squamous intraepithelial lesions (cHSILs) develop as a result of a persistent high-risk human papilloma virus (hrHPV) infection. The natural course of cHSIL is hard to predict, depending on a multitude of viral, clinical, and immunological factors. Local immunity is pivotal in the pathogenesis, spontaneous regression, and progression of cervical dysplasia; however, the underlying mechanisms are unknown. The aim of this review is to outline the changes in the immune microenvironment in spontaneous regression, persistence, and responses to (immuno)therapy. In lesion persistence and progression, the immune microenvironment of cHSIL is characterized by a lack of intraepithelial CD3+, CD4+, and CD8+ T cell infiltrates and Langerhans cells compared to the normal epithelium and by an increased number of CD25+FoxP3+ regulatory T cells (Tregs) and CD163+ M2 macrophages. Spontaneous regression is characterized by low numbers of Tregs, more intraepithelial CD8+ T cells, and a high CD4+/CD25+ T cell ratio. A ‘hot’ immune microenvironment appears to be essential for spontaneous regression of cHSIL. Moreover, immunotherapy, such as imiquimod and therapeutic HPV vaccination, may enhance a preexisting pro-inflammatory immune environment contributing to lesion regression. The preexisting immune composition may reflect the potential for lesion regression, leading to a possible immune biomarker for immunotherapy in cHSILs.

Photosensitizer-induced HPV16 E7 nanovaccines for cervical cancer immunotherapy

There is a lack of effective treatment methods for advanced cervical, and the therapeutic HPV vaccine is a promising option. The design of an efficient therapeutic vaccine is one of the main challenges. In the current study, we constructed a novel HPV nanovaccine that could effectively inhibit the progression of cervical cancer by combining nanotechnology and photodynamic therapy. This nanovaccine was constructed by linking bovine serum albumin (BSA) with the E7 antigen and then encapsulating the photosensitizer and adjuvant through disulfide bonds to form a highly biocompatible and stable structure. Due to its slow-release properties and targeted delivery to lymph nodes combined with infrared laser irradiation of photosensitizers to produce a photo-oxygen response, this vaccine could effectively induce the maturation of dendritic cells and stimulate T cell effects, thereby enhancing antitumor immunity. This prevention and treatment of tumors was experimentally demonstrated in a TC-1 cervical cancer model in C57BL/6 mice. This strategy can be applied to the design of therapeutic HPV vaccines in the future for clinical use.

Vaccine Strategies for Human Papillomavirus-Associated Head and Neck Cancers.

Simple SummaryHuman papillomavirus (HPV) is recognized as a significant risk factor for head and neck cancers worldwide, and it is the most common cause of oropharyngeal cancers in the United States. Here, we review the incidence and pathogenesis of HPV-related cancers, the development and approval of HPV prophylactic vaccines, and the use and effectiveness of HPV vaccines around the world. Furthermore, we discuss advances in the development of HPV therapeutic vaccines as well as its associated challenges.The rising incidence of oropharyngeal squamous cell cancers (OPSCC) in the United States is largely attributed to HPV. Prophylactic HPV vaccines have demonstrated effectiveness against oral infection of HPV 16 and HPV 18. We review the global epidemiology and biology of HPV-related cancers as well as the development of HPV vaccines and their use worldwide. We also review the various strategies and challenges in development of therapeutic HPV vaccines.

Human Papilloma-Virus Associated Carcinomas and Warts

HPV is extremely common worldwide and mainly transmitted through sexual contact; most people are infected with HPV shortly after onset of sexual activity. There are >200 types of HPV, of which at least 12 are cancer-causing (oncogenic or high-risk types). HPV is a causal factor for several anogenital and a subset of oropharyngeal cancers with 2 HPV types (16 and 18) causing 72% of all HPV-associated cancers. Cervical cancer is the fourth most common cancer among women globally with nearly 90% of the deaths occurring in low- and middle-income countries. Comprehensive cervical cancer control includes primary prevention (vaccination against HPV), secondary prevention (screening and treatment of pre-cancerous lesions) as well as treatment of invasive cervical cancer. The currently licensed vaccines are L1 VLP-based and prophylactic; they have been shown to be safe and highly effective in preventing HPV infections and HPV-associated lesions, precancer and cancer. Neutralizing antibodies are the mechanism of protection for prophylactic HPV VLP-based vaccines. Therapeutic HPV vaccines targeting the oncoproteins E6 and E7 are in clinical development.

The Need for Therapeutic HPV Vaccines as a Means of Curbing the Menace of Cervical Cancer

The Need for Therapeutic HPV Vaccines as a Means of Curbing the Menace of Cervical Cancer

Control of Spontaneous HPV16 E6/E7 Expressing Oral Cancer in HLA-A2 (AAD) Transgenic Mice with Therapeutic HPV DNA Vaccine

BackgroundHuman Papillomavirus type 16 (HPV16) has been associated with a subset of head and neck cancers. Two HPV encoded oncogenic proteins, E6 and E7, are important for the malignant progression of HPV-associated cancers. A spontaneous HPV16 E6/E7-expressing oral tumor model in human HLA-A2 (AAD) transgenic mice will be important for the development of therapeutic HPV vaccines for the control of HPV-associated head and neck cancers.MethodsIn the current studies, we characterized the HLA-A2 restricted HPV16 E7-specific CD8 + T cell mediated immune responses in the HLA-A2 (AAD) transgenic mice using a therapeutic naked DNA vaccine encoding calreticulin (CRT) linked to a mutated E7(N53S). We also employed oncogenic DNA plasmids that encoded HPV16E6/E7/Luc, NRasG12V, and sleeping beauty transposase for the transfection into the submucosal of oral cavity of the transgenic mice with electroporation to create a spontaneous oral tumor. Furthermore, we characterized the therapeutic antitumor effects of CRT/E7(N53S) DNA vaccine using the spontaneous HPV16 E6/E7-expressing oral tumor model in HLA-A2 (AAD) transgenic mice.ResultsWe found that CRT/E7(N53S) DNA vaccine primarily generated human HPV16 E7 peptide (aa11-20) specific CD8 + T cells, as compared to the wild-type CRT/E7 vaccine, which primarily generated murine H-2Db restricted E7 peptide (aa49-57) specific CD8 + T cell responses. We also observed transfection of the oncogenic DNA plasmids with electroporation generated spontaneous oral tumor in all of the injected mice. Additionally, treatment with CRT/E7(N53S) DNA vaccine intramuscularly followed by electroporation resulted in significant antitumor effects against the spontaneous HPV16 E6/E7-expressing oral tumors in HLA-A2 (AAD) transgenic mice.ConclusionsTaken together, the data indicated that the combination of HPV16 E6/E7-expressing DNA, NRasG12V DNA and DNA encoding sleeping beauty transposase is able to generate spontaneous oral tumor in HLA-A2 (AAD) transgenic mice, which can be successfully controlled by treatment with CRT/E7(N53S) DNA vaccine. The translational potential of our studies are discussed.

Development of a Novel Mouse Model of Spontaneous High-Risk HPVE6/E7-Expressing Carcinoma in the Cervicovaginal Tract.

Current preclinical models for cervical cancer lack important clinical and pathologic features. To improve upon these models, we aimed to develop a novel, spontaneous HPV16-expressing carcinoma model that captures major aspects of HPV-associated cancer in the female genital tract. This novel preclinical model features (i) expression of HPV oncogenes E6 and E7 in the tumors in female reproductive tract of mice, (ii) spontaneous progression through high-grade squamous intraepithelial lesion (HSIL) to carcinoma, and (iii) flexibility to model cancers from different high-risk HPV genotypes. This was accomplished by injecting plasmids expressing HPV16 E6/E7-luciferase, AKT, c-myc, and Sleeping Beauty transposase into the cervicovaginal tract of C57BL/6 mice followed by electroporation. Cell lines derived from these tumors expressed HPV16 E6/E7 oncogenes, formed tumors in immunocompetent mice, and displayed carcinoma morphology. In all, this novel HPV-associated cervicogenital carcinoma model and HPV16E6/E7-expressing tumor cell line improves upon current HPV16-E6/E7-expressing tumor models. These tumor models may serve as important preclinical models for the development of therapeutic HPV vaccines or novel therapeutic interventions against HPV E6/E7-expressing tumors. SIGNIFICANCE: This study describes the development of a clinically relevant mouse model of cervicovaginal carcinoma that progresses from high-grade lesions and recapitulates key features of human HPV+ cervical cancer.

Prevalence and Risk Factors of Infection with High Risk Human Papilloma Viruses among HIV-Positive Women with Clinical Manifestations of Tuberculosis in a Middle-Income Country.

Women living with HIV-1 are at high risk of infection with human papillomavirus of high carcinogenic risk (HR HPVs). M. tuberculosis (TB) promotes HPV infection and increases the risk to develop HPV-associated cancer. Our knowledge of persisting HR HPVs genotypes, and of the factors promoting HR HPV infection in people living with HIV-1 with clinical TB manifestations is sparse. Here, we analyzed 58 women living with HIV-1 with clinical TB manifestations (WLWH with TB) followed up in specialized centers in Russia, a middle income country endemic for HIV-1 and TB, for the presence in cervical smears of DNA of twelve HR HPV genotypes. DNA encoding HPV16 E5, E6/E7 was sequenced. Sociodemographic data of patients was collected by questionnaire. All women were at C2-C3 stages of HIV-infection (by CDC). The majority were over 30 years old, had secondary education, were unemployed, had sexual partners, experienced 2–3 pregnancies and at least one abortion, and were smokers. The most prevalent was HPV16 detected in the cervical smears of 38% of study participants. Altogether 34.5% of study participants were positive for HR HPV types other than HPV16; however, but none of these types was seen in more than 7% of tested samples. Altogether, 20.7% of study participants were positive for several HR HPV types. Infections with HPVs other than HPV16 were common among WLWH with generalized TB receiving combined ART/TB-therapy, and associated with their ability to work, indirectly reflecting both their health and lifestyle. The overall prevalence of HR HPVs was associated with sexual activity of women reflected by the number of pregnancies, and of HPV 16, with young age; none was associated to CD4+-counts, route of HIV-infection, duration of life with HIV, forms of TB-infection, or duration of ART, characterizing the immune status. Thus, WLWH with TB—especially young—were predisposed to infection with HPV16, advancing it as a basis for a therapeutic HPV vaccine. Phylogenetic analysis of HPV16 E5, E6/E7 DNA revealed no common ancestry; sequences were similar to those of the European and American HPV16 strains, indicating that HPV vaccine for WLWH could be the same as HPV16 vaccines developed for the general population. Sociodemographic and health correlates of HR HPV prevalence in WLWH deserve further analysis to develop criteria/recommendations for prophylactic catch-up and therapeutic HPV vaccination of this highly susceptible and vulnerable population group.

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-β2m–/– 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.

Twenty years of research on HPV vaccines based on genetically modified lactic acid bacteria: an overview on the gut-vagina axis.

Most cervical cancer (CxCa) are related to persistent infection with high-risk human papillomavirus (HR-HPV) in the cervical mucosa, suggesting that an induction of mucosal cell-mediated immunity against HR-HPV oncoproteins can be a promising strategy to fight HPV-associated CxCa. From this perspective, many pre-clinical and clinical trials have proved the potential of lactic acid bacteria (LAB) genetically modified to deliver recombinant antigens to induce mucosal, humoral and cellular immunity in the host. Altogether, the outcomes of these studies suggest that there are several key factors to consider that may offer guidance on improvement protein yield and improving immune response. Overall, these findings showed that oral LAB-based mucosal HPV vaccines expressing inducible surface-anchored antigens display a higher potential to induce particularly specific systemic and mucosal cytotoxic cellular immune responses. In this review, we describe all LAB-based HPV vaccine investigations by reviewing databases from international studies between 2000 and 2020. Our aim is to promote the therapeutic HPV vaccines knowledge and to complete the gaps in this field to empower scientists worldwide to make proper decisions regarding the best strategies for the development of therapeutic HPV vaccines.

881TiP A multi-centre, open-label phase II trial of the combination of VB10.16 and atezolizumab in patients with advanced or recurrent, non-resectable HPV16 positive cervical cancer

HPV16 accounts for almost 60% of the cervical cancer cases. There is an urgent need to develop therapeutic HPV vaccines for control of chronic HPV infection and associated malignancies. HPV16 oncogenes E6/E7 are truly cancer-specific viral antigens and represent ideal targets for a therapeutic HPV16 vaccine. VB10.16 is a targeted DNA-based immunotherapy designed to treat HPV16-associated pre- and malignant lesions. The DNA vaccine encodes a recombinant protein consisting of mutation-inactivated E6 and E7 proteins linked to the natural human chemokine macrophage inflammatory protein-1 alpha (MIP-1α).

Development of multiepitope therapeutic vaccines against the most prevalent high-risk human papillomaviruses.

Aim: Our goal was the development of DNA- or peptide-based multiepitope vaccines targeting HPV E7, E6 and E5 oncoproteins in tumor mouse model. Materials &methods: After designing the multiepitope E7, E6 and E5 constructs from four types of high risk HPVs (16, 18, 31 & 45) using bioinformatics tools, mice vaccination was performed by different homologous and heterologous modalities in a prophylactic setting. Then, anti-tumor effects of the best prophylactic strategies were studied in a therapeutic setting. Results: In both prophylactic and therapeutic experiments, groups receiving homologous E7+E6+E5 polypeptide, and heterologous E7+E6+E5 DNA prime/polypeptide boost were successful in complete rejection of tumors. Conclusion: The designed multiepitope constructs can be considered as promising candidates to develop effective therapeutic HPV vaccines.

1210P - Phase Ib/II trial of TG4001 (Tipapkinogene sovacivec), a therapeutic HPV-vaccine, and Avelumab in patients with recurrent/metastatic (R/M) HPV-16+ cancers

BackgroundTG4001 is a vaccine targeting HPV E6 and E7. It has shown to provide histological clearance of cervical pre-cancerous lesions (Harper DM et al. 2019). We aimed to evaluate in the Ph Ib part the safety of TG4001 in combination with avelumab in HPV 16-positive cancers (NCT03260023). MethodsPatients with HPV-16 positive cancers who had received ≤ 2 prior regimens for R/M disease were enrolled to either one of the two doses of the vaccine (5x106 and 5x107 pfu). TG4001 was administered SC weekly for 6 weeks, every 2 weeks up to M6, and every 12 weeks thereafter. Avelumab was given IV at 10mg/kg every 2 weeks. Tumor response was assessed by RECIST 1.1. For translational and immunological assessments, PBMC samples were collected longitudinally and tissue samples were collected at baseline and D43. ResultsNine patients with oropharyngeal (5), anal (2), cervical (1) or vaginal (1) cancer, were enrolled in this trial, 3 patients on the low dose and 6 patients on the high dose of TG4001. No dose-limiting toxicity and no SAE have been observed. 3 patients had a confirmed partial response according to RECIST1.1. 3/5 evaluable patients for T-cell response by ELISPOT displayed detectable peripheric responses against E6 and/or E7 after treatment, and an overall trend to decreased circulating regulatory T cells (Treg). At the tissue level, 4/5 evaluable patients showed an increase of CD8 infiltration and/or a decrease in infiltrated Treg/CD8 ratio at day 43. The percentage of PD-L1+ cells doubled in all low or moderate expressors. The phenotypic findings were supported by increased expression of genes associated with both adaptive and innate immunity and with a shift from a “cold” tumor to a “hot” tumor gene signature. ConclusionsThe combination of TG4001 and avelumab is safe and provides anti-tumor activity in HPV-16+ cancer patients. The treatment induces immune changes in patients with poor baseline immune contexture. The combination is being evaluated in the ongoing Ph II part. Clinical trial identificationNCT03260023. Legal entity responsible for the studyTransgene SA. FundingTransgene. DisclosureC. Le Tourneau: Advisory / Consultancy: MSD; Advisory / Consultancy: BMS; Advisory / Consultancy: Merck Serono; Advisory / Consultancy: Roche; Advisory / Consultancy: Amgen; Advisory / Consultancy: AstraZeneca; Advisory / Consultancy: Nanobiotix; Advisory / Consultancy: GSK. J. Delord: Honoraria (self), Advisory / Consultancy: Merck; Honoraria (self), Advisory / Consultancy: Novartis; Honoraria (self): Roche; Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution): BMS; Honoraria (self), Research grant / Funding (institution): MSD; Advisory / Consultancy: EMD Serono; Research grant / Funding (institution): Genentech; Research grant / Funding (institution): AstraZeneca. P. Cassier: Honoraria (self), Research grant / Funding (institution), Travel / Accommodation / Expenses: Novartis; Honoraria (self), Research grant / Funding (institution), Travel / Accommodation / Expenses: Roche/Genentech; Honoraria (self), Research grant / Funding (institution): Blueprint Medicines; Honoraria (self), Travel / Accommodation / Expenses: Amgen; Research grant / Funding (institution): Lilly; Research grant / Funding (institution): Bayer; Research grant / Funding (institution): AstraZeneca; Research grant / Funding (institution): Celgene; Research grant / Funding (institution): Plexxikon; Research grant / Funding (institution): AbbVie; Research grant / Funding (institution), Travel / Accommodation / Expenses: BMS; Research grant / Funding (institution): Merck Serono; Research grant / Funding (institution), Travel / Accommodation / Expenses: Merck Sharp & Dohme; Research grant / Funding (institution): Taiho Pharmaceuticals; Research grant / Funding (institution): Toray Industries; Research grant / Funding (institution): Transgene; Research grant / Funding (institution): Loxo; Research grant / Funding (institution): GlaxoSmithKline; Research grant / Funding (institution): Innate Pharma; Research grant / Funding (institution): Janssen. D. Loirat: Advisory / Consultancy: Roche; Advisory / Consultancy: BMS; Advisory / Consultancy: MSD. A. Tavernaro: Full / Part-time employment: Transgene SA. B. Bastien: Full / Part-time employment, Employed by sponsor of the study: Transgene SA. K. Bendjama: Shareholder / Stockholder / Stock options, Full / Part-time employment: Transgene.

Therapeutic Vaccines Against Human Papilloma Viruses: Achievements and Prospects.

Human papillomaviruses of high carcinogenic risk (HR HPVs) are major etiological agents of malignant diseases of the cervix, vulva, penis, anal canal, larynx, head, and neck. Prophylactic vaccination against HPV, which mainly covers girls and women under 25, does not prevent vertical and horizontal HPV transmission in infants and children and does not have a therapeutic effect. As a result, a significant proportion of the population is not protected from the HPV infection and development of HPV-associated neoplastic transformation and cancer, which indicates the need for development and introduction of therapeutic HPV vaccines. Unlike prophylactic vaccines aimed at the formation of virus-neutralizing antibodies, therapeutic vaccines elicit cellular immune response leading to the elimination of infected and malignant cells expressing viral proteins. The ideal targets for vaccine immunotherapy are highly conserved HR HPV oncoproteins E6 and E7 expressed in precancerous and tumor tissues. Here, we describe expression of these proteins during different stages of HPV infection, their antigenic and immunogenic properties, and T-cell epitopes, the response to which correlates with natural regression of HPV-induced neoplastic changes. The review describes patterns of E6 and E7 oncoproteins presentation to the immune system as components of candidate vaccines along with the results of the most promising preclinical trials and animal models used in these trials. Special attention is paid to vaccine candidates which have shown efficacy in clinical trials in patients with HPV-associated neoplastic changes.

Bioproduction of a Therapeutic Vaccine Against Human Papillomavirus in Tomato Hairy Root Cultures

Human papillomavirus (HPV) tumor disease is a critical public health problem worldwide, especially in the developing countries. The recognized pathogenic function of E5, E6, and E7 oncoproteins offers the opportunity to devise therapeutic vaccines based on engineered recombinant proteins. The potential of plants to manufacture engineered compounds for pharmaceutical purposes, from small to complex protein molecules, allows the expression of HPV antigens and, possibly, the regulation of immune functions to develop very specific therapies as a reinforcement to available nonspecific therapies and preventive vaccination also in developed countries. Among plant-based expression formats, hairy root cultures are a robust platform combining the benefits of eukaryotic plant-based bioreactors, with those typical of cell cultures. In this work, to devise an experimental therapeutic vaccine against HPV, hairy root cultures were used to express a harmless form of the HPV type 16 E7 protein (E7*) fused to SAPKQ, a noncytotoxic form of the saporin protein from Saponaria officinalis, that we had shown to improve E7-specific cell-mediated responses as a fusion E7*-SAPKQ DNA vaccine. Hairy root clones expressing the E7*-SAPKQ candidate vaccine were obtained upon infection of leaf explants of Solanum lycopersicum using a recombinant plant expression vector. Yield was approximately 35.5 μg/g of fresh weight. Mouse immunization with vaccine-containing crude extracts was performed together with immunological and biological tests to investigate immune responses and anticancer activity, respectively. Animals were primed with either E7*-SAPKQ DNA-based vaccine or E7*-SAPKQ root extract-based vaccine and boosted with the same (homologous schedule) or with the other vaccine preparation (heterologous schedule) in the context of TC-1 experimental mouse model of HPV-associated tumor. All the formulations exhibited an immunological response associated to anticancer activity. In particular, DNA as prime and hairy root extract as boost demonstrated the highest efficacy. This work, based on the development of low-cost technologies, highlights the suitability of hairy root cultures as possible biofactories of therapeutic HPV vaccines and underlines the importance of the synergic combination of treatment modalities for future developments in this field.

Cervical microbiome role in outcomes of therapeutic HPV vaccination for cervical intraepithelial neoplasia.

3099Background: Clinical trials have suggested that the gut microbiome can modulate immunotherapy outcomes with checkpoint inhibitors (Kroemer et al, Nat rev immunology. Jan 2018). However, the rol...