HPV vaccines: Global perspectives

The potential use of therapeutics and prophylactic mRNA vaccines in human papillomavirus (HPV)

Cervical cancer (CC) and other malignant malignancies are acknowledged to be primarily caused by persistent human papillomavirus (HPV) infection. Historically, vaccinations against viruses that produce neutralizing antibodies unique to the virus have been an affordable way to manage viral diseases. CC risk is decreased, but not eliminated, by HPV vaccinations. Since vaccinations have been made available globally, almost 90% of HPV infections have been successfully avoided. On the lesions and diseases that are already present, however, no discernible treatment benefit has been shown. As a result, therapeutic vaccines that elicit immune responses mediated by cells are necessary for the treatment of established infections and cancers. mRNA vaccines possess remarkable potential in combating viral diseases and malignancy as a result of their superior industrial production, safety, and efficacy. Furthermore, considering the expeditiousness of production, the mRNA vaccine exhibits promise as a therapeutic approach targeting HPV. Given that the HPV-encoded early proteins, including oncoproteins E6 and E7, are consistently present in HPV-related cancers and pre-cancerous lesions and have crucial functions in the progression and persistence of HPV-related diseases, they serve as ideal targets for therapeutic HPV vaccines. The action mechanism of HPV and HPV-related cancer mRNA vaccines, their recent advancements in clinical trials, and the potential for their therapeutic applications are highlighted in this study, which also offers a quick summary of the present state of mRNA vaccines. Lastly, we highlight a few difficulties with mRNA HPV vaccination clinical practice and provide our thoughts on further advancements in this quickly changing sector. It is expected that mRNA vaccines will soon be produced quickly for clinical HPV prevention and treatment.

Improving Influenza Vaccination Coverage in Patients with Cancer: A Position Paper from a Multidisciplinary Expert Group

Patients with cancer can be immunocompromised because of their disease and/or due to anticancer therapy. In this population, severe influenza virus infections are associated with an elevated risk of morbidity and mortality. Influenza vaccination is therefore highly recommended in cancer patients, including those receiving anticancer therapy. However, vaccination coverage remains far below the recommended target for vulnerable subjects. Six specialists in oncology, hematology, immunology, and public health/vaccinology convened with the objective of developing strategies, based on evidence and clinical experience, for improving influenza vaccination coverage in cancer patients. This viewpoint provides an overview of current influenza vaccination recommendations in cancer patients, discusses barriers to vaccination coverage, and presents strategies for overcoming said barriers. New immunization issues raised by the COVID-19 pandemic are also addressed. Future directions include improving public education on influenza vaccination, providing the media with accurate information, improving knowledge among healthcare professionals, improving access to vaccines for cancer patients, co-administration of the influenza and COVID-19 vaccines, increased collaboration between oncologists and other health professionals, increased accessibility of digital vaccination registries to specialists, shared information platforms, and promoting immunization campaigns by healthcare systems with the support of scientific societies.

An evaluation of the cost of human papilloma virus (HPV) vaccine delivery in Zambia

BACKGROUND

Human papillomavirus (HPV) is a common sexually transmitted infection and the leading cause of cervical cancer. The HPV vaccine is a safe and effective way to prevent HPV infection. In Zambia, the vaccine is given during Child Health Week to girls aged 14 years who are in and out of school in two doses over two years. The focus of this evaluation was to establish the cost to administer a single dose of the vaccine as well as for full immunisation of two doses.

METHODS

This work was part of a broader study on assessing HPV programme implementation in Zambia. For HPV costing aspect of the study, with a healthcare provider perspective and reference year of 2020, both top-down and micro-costing approaches were used for financial costing, depending on the cost data source, and economic costs were gathered as secondary data from Expanded Programme for Immunisation Costing and Financing Project (EPIC), except human resource costs which were gathered as primary data using existing Ministry of Health salary scales and reported time spent by different health cadres on activities related to HPV vaccination. Data was collected from eight districts in four provinces, mainly using a structured questionnaire, document reviews and key informant interviews with staff at national, provincial, district and health facility levels. Administrative coverage rates were obtained for each district.

RESULTS

Findings show that schools made up 53.3% of vaccination sites, community outreach sites 30.9% and finally health facilities 15.8%. In terms of coverage for 2020, for the eight districts sampled, schools had the highest coverage at 96.0%. Community outreach sites were at 6.0% of the coverage and health facilities accounted for only 1.0% of the coverage. School based delivery had the lowest economic cost at USD13.2 per dose and USD 28.1 per fully immunised child (FIC). Overall financial costs for school based delivery were US$6.0 per dose and US$12.4 per FIC. Overall economic costs taking all delivery models into account were US$23.0 per dose and US$47.6 per FIC. The main financial cost drivers were microplanning, supplies, service delivery/outreach and vaccine co-financing; while the main economic cost drivers were human resources, building overhead and vehicles. Nurses, environmental health technicians and community-based volunteers spent the most time on HPV related vaccination activities compared to other cadres and represented the greatest human resource costs.

CONCLUSIONS

The financial cost of HPV vaccination in Zambia aligns favourably with similar studies conducted in other countries. However, the economic costs appear significantly higher than those observed in most international studies. This discrepancy underscores the substantial strain placed on healthcare resources by the program, a burden that often remains obscured. While the vaccine costs are currently subsidized through the generous support of Gavi, the Vaccine Alliance, it's crucial to recognize that these expenses pose a considerable threat to long-term sustainability. Consequently, countries such as Zambia must proactively devise strategies to address this challenge.

An engineered Accum-E7 protein-based vaccine with dual anti-cervical cancer activity

Worldwide prevalence of cervical cancer decreased significantly with the use of human papilloma virus (HPV)-targeted prophylactic vaccines. However, these multivalent antiviral vaccines are inert against established tumors, which leave patients with surgical ablative options possibly resulting in long-term reproductive complications and morbidity. In an attempt to bypass this unmet medical need, we designed a new E7 protein-based vaccine formulation using Accum™, a technology platform designed to promote endosome-to-cytosol escape as a means to enhance protein accumulation in target cells. Prophylactic vaccination of immunocompetent mice using the Accum-E7 vaccine (aE7) leads to complete protection from cervical cancer despite multiple challenges conducted with ascending C3.43 cellular doses (0.5-, 1.0-, and 2.0 × 106 cells). Moreover, the humoral response induced by aE7 was higher in magnitude compared with naked E7 protein vaccination and displayed potent inhibitory effects on C3.43 proliferation in vitro. When administered therapeutically to animals with pre-established C3.43 or Tal3 tumors, the vaccine-induced response synergized with multiple immune checkpoint blockers (anti-PD-1, anti-CTLA4, and anti-CD47) to effectively control tumor growth. Mechanistically, the observed therapeutic effect requires cross-presenting dendritic cells as well as CD8 T cells predominantly, with a non-negligible role played by both CD4+ and CD19+ lymphocytes. good laboratory practice (GLP) studies revealed that aE7 is immunogenic and well tolerated by immunocompetent mice with no observed adverse effects despite the use of a fourfold exceeding dose. In a nutshell, aE7 represents an ideal vaccine candidate for further clinical development as it uses a single engineered protein capable of exhibiting both prophylactic and therapeutic activity.

Cervical HPV infection in Guangzhou, China: an epidemiological study of 198,111 women from 2015 to 2021

Persistent high-risk human papillomavirus (HPV) infection is the pivotal cause of cervical carcinogenesis. HPV types distribution varies greatly by region, and its long-term changes of prevalence remain to be fully characterized in China. Here, the largest population of 198,111 consecutive women who underwent routine cervical screening were investigated from 2015 to 2021 in Guangzhou, south China. The results showed that the overall HPV prevalence was 21.66% (42,911/198,111), and the annual prevalence increased significantly from 2015 to 2021 (p < 0.001). HPV52, 16, 58, CP8304, 51, 53, 39, and 68 were the most prevalent HPV types. The relative HPV-positive rate correlated positively with the progression of cervical intraepithelial neoplasia (p < 0.001); HPV16 was the predominant carcinogenic type, followed by HPV52 and HPV18. HPV infections were significantly age-specific, and 26.51% (11,375/42,911) of cases were caused by multiple HPV types. In addition, HPV infections typically cleared over a median time of 16 (interquartile range 9-31) months, and the clearance of HPV16 was significantly faster than that of other types (p < 0.001). These findings may serve as a guide for local governments to evaluate HPV vaccination and cervical cancer prevention strategies in south China.

Human Papillomavirus Infection in Penile Cancer: Multidimensional Mechanisms and Vaccine Strategies

Penile cancer (PC) is a rare male malignant tumor, with early lymph node metastasis and poor prognosis. Human papillomavirus (HPV) plays a key role in the carcinogenesis of PC. This review aims to summarize the association between HPV infection and PC in terms of virus-host genome integration patterns (the disrupted regions in the HPV and PC genome), genetic alterations, and epigenetic regulation (methylation and microRNA modification) occurring in HPV and PC DNA, as well as tumor immune microenvironment reprogramming. In addition, the potential of HPV vaccination strategies for PC prevention and treatment is discussed. Understanding of the HPV-related multidimensional mechanisms and the application of HPV vaccines will promote rational and novel management of PC.

An Evaluation of the Cost of Human Papilloma Virus (HPV) Vaccine Delivery In Zambia

Background

Human papillomavirus (HPV) is a common sexually transmitted infection and the leading cause of cervical cancer. The HPV vaccine is a safe and effective way to prevent HPV infection. In Zambia, the vaccine is given during Child Health to girls aged 14 years who are in and out of school in two doses over two years. The focus of this evaluation was to establish the cost to administer a single dose of the vaccine well as for full immunisation of two doses.

Methods

For HPV costing, both top-down and micro-costing approaches were used, depending on the cost data source, and economic costs were gathered from Expanded Programme for Immunisation Costing and Financing Project (EPIC). Data was collected from eight districts in four provinces, mainly using a structured questionnaire, document reviews and key informant interviews with staff at national, district and provincial levels.

Results

Findings show that schools made up 53.3% of vaccination sites, community outreach sites 30.9% and finally health facilities 15.8%. In terms of coverage for 2020, for the eight districts sampled, schools had the highest coverage at 96.0%. Community outreach sites were at 6.0% of the coverage and health facilities accounted for only 1.0% of the coverage. School based delivery had the lowest cost economic cost at USD13.2 per dose and USD 26.4 per fully immunised child (FIC). Overall financial costs were US$6.0 per dose and US$11.9 per fully immunised child. Overall economic costs taking all delivery models into account were US$23.0 per dose and US$46.0 per FIC. The main cost drivers were human resources, building overhead and vehicles, microplanning, supplies and service delivery/outreach. were the top cost drivers. Nurses, environmental health technicians and community-based volunteers were the most involved in HPV vaccination.

Conclusions

Future planning in Zambia and other African countries conducting HPV vaccination needs to prioritise these cost drivers as well as possibly find strategies to minimise some costs. Although not a challenge now due to Gavi support, vaccine costs are a major threat to sustainability in the long run. Countries like Zambia must find strategies to mitigate against this.

Immunogenicity and safety of two novel human papillomavirus 4- and 9-valent vaccines in Chinese women aged 20-45 years: A randomized, blinded, controlled with Gardasil (type 6/11/16/18), phase III non-inferiority clinical trial

BACKGROUND

Human papillomavirus (HPV) infections were the main cause of anogenital cancers and warts. HPV 6/11/16/18 vaccines provide protection against the high-risk types of HPV responsible for 70% of cervical cancers and 90% of genital warts. This randomized, blinded, non-inferiority phase III trial was to determine whether immunogenicity and tolerability would be non-inferior among women after receiving two novel 4- and 9-valent HPV vaccines (4vHPV, HPV 6/11/16/18; 9vHPV, HPV 6/11/16/18/31/33/45/52/58) compared with those receiving Gardasil 4 (4-valent).

METHODS

1680 females between 20 and 45 years were randomized in a 2:1:1 ratio to 20-26, 27-35, or 36-45 y groups. Subjects then equally assigned to receive 4vHPV, 9vHPV or Gardasil 4 (control) vaccine at months 0, 2, and 6. End points included non-inferiority of HPV-6/11/16/18 antibodies for 4vHPV versus control, and 9vHPV versus control and safety. The immunogenicity non-inferiority was pre-defined as the lower bound of 95% confidence interval (CI) of seroconversion rate (SCR) difference > -10% and the lower bound of 95% CI of geometric mean antibody titer (GMT) ratio > 0.5.

RESULTS

Among the three vaccine groups, more than 99% of the participants seroconverted to all 4 HPV types. The pre-specified statistical non-inferiority criterion for the immunogenicity hypothesis was met: all the lower bounds of 95% CIs on SCR differences exceeded -10% for each vaccine HPV type and the corresponding lower bounds of 95% CIs for GMT ratios > 0.5. Across vaccination groups, the most common vaccination reaction were injection-site adverse events (AEs), including pain, swelling, and redness. General and serious AEs were similar in the three groups. There were no deaths.

CONCLUSIONS

This study demonstrated that the novel 4- and 9-valent HPV vaccination was highly immunogenic and generally well tolerated, both of which were non-inferior to Gardasil 4 in immunogenicity and safety.

Next generation L2-based HPV vaccines cross-protect against cutaneous papillomavirus infection and tumor development

Licensed L1-VLP-based immunizations against high-risk mucosal human papillomavirus (HPV) types have been a great success in reducing anogenital cancers, although they are limited in their cross-protection against HPV types not covered by the vaccine. Further, their utility in protection against cutaneous HPV types, of which some contribute to non-melanoma skin cancer (NMSC) development, is rather low. Next generation vaccines achieve broadly cross-protective immunity against highly conserved sequences of L2. In this exploratory study, we tested two novel HPV vaccine candidates, HPV16 RG1-VLP and CUT-PANHPVAX, in the preclinical natural infection model Mastomys coucha. After immunization with either vaccines, a mock control or MnPV L1-VLPs, the animals were experimentally infected and monitored. Besides vaccine-specific seroconversion against HPV L2 peptides, the animals also developed cross-reactive antibodies against the cutaneous Mastomys natalensis papillomavirus (MnPV) L2, which were cross-neutralizing MnPV pseudovirions in vitro. Further, both L2-based vaccines also conferred in vivo protection as the viral loads in plucked hair after experimental infection were lower compared to mock-vaccinated control animals. Importantly, the formation of neutralizing antibodies, whether directed against L1-VLPs or L2, was able to prevent skin tumor formation and even microscopical signs of MnPV infection in the skin. For the first time, our study shows the proof-of-principle of next generation L2-based vaccines even across different PV genera in an infection animal model with its genuine PV. It provides fundamental insights into the humoral immunity elicited by L2-based vaccines against PV-induced skin tumors, with important implications to the design of next generation HPV vaccines.

The potential of urine for human papillomavirus-related cervical cancer prevention

Cervical cancer is one of the most preventable cancers. The introduction of human papillomavirus (HPV) vaccines and the adaptation of regular screening programs are key actions that need to be generalized globally to achieve the goal of cervical cancer elimination. However, it is still challenging to achieve satisfactory coverage rate, and many women are reluctant to participate in gynecologic examination. In this article, we review the research on the application of HPV detection in urine samples for cervical cancer screening and vaccine monitoring, as well as discuss the technical challenges and new technological advancements in urine-based tests. HPV detection in urine is an excellent noninvasive alternative that is widely accepted by women, relatively affordable, and provides the potential to reach women without the necessity for clinical visits. Thus, it is an attractive tool for both cervical cancer screening and vaccine monitoring.

Virus against virus: strategies for using adenovirus vectors in the treatment of HPV-induced cervical cancer

Although most human papillomavirus (HPV) infections are harmless, persistent infection with high-risk types of HPV is known to be the leading cause of cervical cancer. Following the infection of the epithelium and integration into the host genome, the oncogenic proteins E6 and E7 disrupt cell cycle control by inducing p53 and retinoblastoma (Rb) degradation. Despite the FDA approval of prophylactic vaccines, there are still issues with cervical cancer treatment; thus, many therapeutic approaches have been developed to date. Due to strong immunogenicity, a high capacity for packaging foreign DNA, safety, and the ability to infect a myriad of cells, adenoviruses have drawn attention of researchers. Adenovirus vectors have been used for different purposes, including as oncolytic agents to kill cancer cells, carrier for RNA interference to block oncoproteins expression, vaccines for eliciting immune responses, especially in cytotoxic T lymphocytes (CTLs), and gene therapy vehicles for restoring p53 and Rb function.

Engineered SARS-CoV-2 receptor binding domain improves manufacturability in yeast and immunogenicity in mice

Global containment of COVID-19 still requires accessible and affordable vaccines for low- and middle-income countries (LMICs). Recently approved vaccines provide needed interventions, albeit at prices that may limit their global access. Subunit vaccines based on recombinant proteins are suited for large-volume microbial manufacturing to yield billions of doses annually, minimizing their manufacturing cost. These types of vaccines are well-established, proven interventions with multiple safe and efficacious commercial examples. Many vaccine candidates of this type for SARS-CoV-2 rely on sequences containing the receptor-binding domain (RBD), which mediates viral entry to cells via ACE2. Here we report an engineered sequence variant of RBD that exhibits high-yield manufacturability, high-affinity binding to ACE2, and enhanced immunogenicity after a single dose in mice compared to the Wuhan-Hu-1 variant used in current vaccines. Antibodies raised against the engineered protein exhibited heterotypic binding to the RBD from two recently reported SARS-CoV-2 variants of concern (501Y.V1/V2). Presentation of the engineered RBD on a designed virus-like particle (VLP) also reduced weight loss in hamsters upon viral challenge.

In Silico Design and Immunological Studies of Two Novel Multiepitope DNA-Based Vaccine Candidates Against High-Risk Human Papillomaviruses

Human papillomaviruses (HPV)-16 and 18 are the most prevalent types associated with cervical cancer. HPV L1 and L2 capsid proteins and E7 oncoprotein play crucial roles in HPV-related diseases. Hence, these proteins were proposed as target antigens for preventive and therapeutic vaccines. In this study, two multiepitope DNA-based HPV vaccine candidates were designed using in silico analysis including the immunogenic and conserved epitopes of HPV16/18 L1, L2 and E7 proteins (the L1-L2-E7 fusion DNA), and of heat shock protein 70 (HSP70) linked to the L1-L2-E7 DNA construct (the HSP70-L1-L2-E7 fusion DNA). Next, the expression of the L1-L2-E7 and HSP70-L1-L2-E7 multiepitope DNA constructs was evaluated in a mammalian cell line. Finally, immunological responses and antitumor effects of the DNA constructs were investigated in C57BL/6 mice. Our data indicated high expression rates of the designed multiepitope L1-L2-E7 DNA (~ 56.16%) and HSP70-L1-L2-E7 DNA (~ 80.45%) constructs in vitro. The linkage of HSP70 epitopes to the L1-L2-E7 DNA construct significantly increased the gene expression. Moreover, the HSP70-L1-L2-E7 DNA construct could significantly increase immune responses toward Th1 response and CTL activity, and induce stronger antitumor effects in mouse model. Thus, the designed HSP70-L1-L2-E7 DNA construct represents promising results for development of HPV DNA vaccine candidates.

A Review on Cancer Immunotherapy and Applications of Nanotechnology to Chemoimmunotherapy of Different Cancers

Clinically, different approaches are adopted worldwide for the treatment of cancer, which still ranks second among all causes of death. Immunotherapy for cancer treatment has been the focus of attention in recent years, aiming for an eventual antitumoral effect through the immune system response to cancer cells both prophylactically and therapeutically. The application of nanoparticulate delivery systems for cancer immunotherapy, which is defined as the use of immune system features in cancer treatment, is currently the focus of research. Nanomedicines and nanoparticulate macromolecule delivery for cancer therapy is believed to facilitate selective cytotoxicity based on passive or active targeting to tumors resulting in improved therapeutic efficacy and reduced side effects. Today, with more than 55 different nanomedicines in the market, it is possible to provide more effective cancer diagnosis and treatment by using nanotechnology. Cancer immunotherapy uses the body's immune system to respond to cancer cells; however, this may lead to increased immune response and immunogenicity. Selectivity and targeting to cancer cells and tumors may lead the way to safer immunotherapy and nanotechnology-based delivery approaches that can help achieve the desired success in cancer treatment.

Engineered SARS-CoV-2 receptor binding domain improves immunogenicity in mice and elicits protective immunity in hamsters

Global containment of COVID-19 still requires accessible and affordable vaccines for low- and middle-income countries (LMICs).1 Recently approved vaccines provide needed interventions, albeit at prices that may limit their global access.2 Subunit vaccines based on recombinant proteins are suited for large-volume microbial manufacturing to yield billions of doses annually, minimizing their manufacturing costs.3 These types of vaccines are well-established, proven interventions with multiple safe and efficacious commercial examples.4-6 Many vaccine candidates of this type for SARS-CoV-2 rely on sequences containing the receptor-binding domain (RBD), which mediates viral entry to cells via ACE2.7,8 Here we report an engineered sequence variant of RBD that exhibits high-yield manufacturability, high-affinity binding to ACE2, and enhanced immunogenicity after a single dose in mice compared to the Wuhan-Hu-1 variant used in current vaccines. Antibodies raised against the engineered protein exhibited heterotypic binding to the RBD from two recently reported SARS-CoV-2 variants of concern (501Y.V1/V2). Presentation of the engineered RBD on a designed virus-like particle (VLP) also reduced weight loss in hamsters upon viral challenge.

Effectiveness of a universal vaccination program with an HPV quadrivalent vaccine in young Brazilian women

We examined human papillomavirus (HPV) vaccine effectiveness in a nationwide sample of women aged 16 to 25 years who utilized the public health system in Brazil. This was a cross-sectional, multicentric survey conducted between September 2016 and November 2017 (POP-Brazil Study). A total of 5,945 young adult women were recruited from 119 public primary care units from all 27 federative units of Brazil by trained health professionals. The participants participated in a face-to-face interview and provided biological samples for genital HPV analysis. HPV genotyping was performed using a Linear Array HPV genotyping test in a central laboratory. Sampling weights were applied to the data. Overall, 11.92% (95% CI 10.65, 13.20) of the participants reported having been vaccinated. The frequency of vaccination was highest in 16- to 17-year-old women, with a decreasing vaccination rate with increasing age, and vaccinated women were more likely to belong to the high socioeconomic status group. The use of a quadrivalent vaccine decreased the HPV types 6, 11, 16, and 18 by 56.78%, from 15.64% in unvaccinated women to 6.76% in vaccinated women (P < 0.01), even after adjustment for age. Those who received the vaccine had lower HPV 16 (2.34% in vaccinated vs 8.91% in unvaccinated, P < 0.01) and 6 rates (2.06% vs 5.77%, P < 0.01). Additionally, a higher rate of high-risk HPV types other than HPV 16 and 18 (40.47% in vaccinated vs 32.63% in unvaccinated, P < 0.01) was observed. In conclusion, the results of this study support the effectiveness of HPV vaccination in Brazil. Continuous surveillance must be assured to monitor the HPV infection rate in the vaccination era.

Evidence for Missing Positive Results for Human Papilloma Virus 45 (HPV-45) and HPV-59 with the SPF10-DEIA-LiPA25 (Version 1) Platform Compared to Type-Specific Real-Time Quantitative PCR Assays and Impact on Vaccine Effectiveness Estimates

Human papillomavirus (HPV) epidemiological and vaccine studies require highly sensitive HPV detection systems. The widely used broad-spectrum SPF₁₀-DEIA-LiPA₂₅ (SPF₁₀ method) has reduced sensitivity toward HPV-45 and -59. Therefore, anogenital samples from the PASSYON study were retrospectively analyzed with type-specific (TS) HPV-45 and -59 real-time quantitative PCR (qPCR) assays. The SPF₁₀ method missed 51.1% of HPV-45 and 76.1% of HPV-59 infections that were detected by the TS qPCR assays.

Human papillomavirus (HPV) epidemiological and vaccine studies require highly sensitive HPV detection systems. The widely used broad-spectrum SPF₁₀-DEIA-LiPA₂₅ (SPF₁₀ method) has reduced sensitivity toward HPV-45 and -59. Therefore, anogenital samples from the PASSYON study were retrospectively analyzed with type-specific (TS) HPV-45 and -59 real-time quantitative PCR (qPCR) assays. The SPF₁₀ method missed 51.1% of HPV-45 and 76.1% of HPV-59 infections that were detected by the TS qPCR assays. The viral copy number (VCn) of SPF₁₀-missed HPV-45 and -59 was significantly lower than SPF₁₀-detected HPV-45 and -59 (P < 0.0001 for both HPV types). Sanger sequencing showed no phylogenetic distinction between SPF₁₀-missed and SPF₁₀-detected HPV-59 variants, but variants bearing the A6562G single-nucleotide polymorphism (SNP) in the SPF₁₀ target region were more likely to be missed (P = 0.0392). HPV cooccurrence slightly influenced the detection probability of HPV-45 and -59 with the SPF₁₀ method. Moreover, HPV-59 detection with the SPF₁₀ method was hampered more in nonvaccinated women than vaccinated women, likely due to a stronger masking effect by increased HPV cooccurrence in the former group. Consequently, the SPF₁₀ method led to a strong negative vaccine effectiveness (VE) of –84.6% against HPV-59, while the VE based on TS qPCR was 3.1%. For HPV-45, the relative increase in detection in nonvaccinated women compared vaccinated women was more similar, resulting in comparable VE estimates. In conclusion, this study shows that HPV-45 and -59 detection with the SPF₁₀ method is dependent on factors including VCn, HPV cooccurrence, and vaccination, thereby showing that knowledge of the limitations of the HPV detection method used is of great importance.

Impact of Vaccines; Health, Economic and Social Perspectives

In the 20th century, the development, licensing and implementation of vaccines as part of large, systematic immunization programs started to address health inequities that existed globally. However, at the time of writing, access to vaccines that prevent life-threatening infectious diseases remains unequal to all infants, children and adults in the world. This is a problem that many individuals and agencies are working hard to address globally. As clinicians and biomedical scientists we often focus on the health benefits that vaccines provide, in the prevention of ill-health and death from infectious pathogens. Here we discuss the health, economic and social benefits of vaccines that have been identified and studied in recent years, impacting all regions and all age groups. After learning of the emergence of SARS-CoV-2 virus in December 2019, and its potential for global dissemination to cause COVID-19 disease was realized, there was an urgent need to develop vaccines at an unprecedented rate and scale. As we appreciate and quantify the health, economic and social benefits of vaccines and immunization programs to individuals and society, we should endeavor to communicate this to the public and policy makers, for the benefit of endemic, epidemic, and pandemic diseases.

Candidate HPV genotypes not included in the 9-valent vaccine for prevention of CIN 2-3

OBJECTIVES

To identify the prevalence of human papillomavirus genotypes - as a single infection or co-infection - not included in the 9-valent (9v) HPV vaccine among women with cervical intraepithelial neoplasia (CIN 2-3).

METHODS

Retrospective study of 1700 women referred due to abnormal cytology to Sant Joan de Deu Hospital. We selected 849 patients with CIN 2 or CIN 3 diagnosis confirmed by biopsy. An HPV test, a second cytology, and colposcopy were performed on all patients.Those with abnormal colposcopy underwent cervical biopsy. Patients with abnormal cytology and normal colposcopy or transformation zone type 3 underwent endocervical curetage. Conization was performed if punch biopsy or endocervical curetage confirmed CIN 2-3 or if a CIN 1 lesion persisted (diagnosed by biopsy) over 2 years in patients over 25 years of age. Comparisons for qualitative variables were analyzed with the chi-squared test. Analysis of variance was used for comparisons involving more than two samples.

RESULTS

HPV was detected in 746 of 849 patients (87.9%) and in 306 (41%) of those where more than one HPV genotype was present. The more frequent genotypes detected as single infection were: HPV-16 (267/849%-31.4%), HPV 31 (34/849-4%), HPV-33 (20/849%-2.4%), HPV-58 (17/849%-2%), HPV-51 (15/849%-1.8%), and HPV-53 (12/849%-1.4%). The more frequent genotypes isolated including multiple HPV infection were HPV-16 (427/849%-50.2%), HPV-31 (108/849%-12.7%), HPV-51 (79/849%-9.3%), HPV-33 (67/849%-7.8%), HPV-58 (67/849%-7.8%), and HPV-52 (59/849%-6.9%). In total, 78% of women diagnosed with CIN 2 or CIN 3 had an infection by a HPV genotype included in the 9v vaccine. Of the 849 women diagnosed with CIN 2 or CIN 3, 103 (12.1%) tested negative for HPV and 106 (12.4%) tested positive for low-risk HPV types.

CONCLUSIONS

Inclusion of HPV-51, 53, 66, and 35 in a new vaccine may not be advisable as most are detected as coinfection with other high-risk genotypes that are already included in the current vaccines.

HPV genotypic spectrum in Jilin province, China, where non-vaccine-covered HPV53 and 51 are prevalent, exhibits a bimodal age-specific pattern

Background

Human papillomavirus (HPV), the most common sexually transmitted disease, is involved in a series of other diseases. The persistent infection of high-risk HPVs (HR-HPVs) is considered to be the causative agent of cervical cancer, and it is related to noncervical cancers. The present study aims to estimate the HPV prevalence and genotype distribution in Jilin province, China, to guide HPV-related cervical cancer screening and HPV vaccination.

Methods

From October 2017 to September 2019, 21,282 samples (634 male and 20,648 female) were collected for HPV infection detection using an HPV genotyping panel. The age-related HPV prevalence and morbidity of HPV-based disease and HPV prevalence associated with specific diseases were analyzed.

Results

A total of 7095 (34.4%) positive for HPV infection of 20648 women, and 164 (25.8%) positive of 634 men. The HPV prevalence among women exhibited a bimodal pattern, with a peak in young group and a second peak in old group, with increased severity of cervical lesions. HPV16 (7.8%), HPV52 (5.8%), HPV58 (5.0%), HPV53 (3.4%), and HPV51 (3.0%) were the most prevalent genotypes among women, and HPV6 (6.0%), HPV11 (5.7%), HPV16 (3.6%), HPV18 (2.7%), and HPV51 (3.0%) were prevalent among men. Non-vaccine-covered HPV53 and 51 were found in 6.3% of HPV infection and 8.9% of cervical cancer in Jilin province. Furthermore, 45.5% of females and 28.6% of males with genital warts were infected with HR-HPV genotypes.

Conclusion

The HPV genotypic spectrum in Jilin province, where non-vaccine-covered HPV53 and 51 were prevalent, exhibited an age- and cervical lesion-specific pattern, which provides guidance for HPV vaccination and cervical cancer screening. HPV infection in men and benign hyper-proliferative lesions should not be neglected.

The Delay in the Licensing of Protozoal Vaccines: A Comparative History

Although viruses and bacteria have been known as agents of diseases since 1546, 250 years went by until the first vaccines against these pathogens were developed (1796 and 1800s). In contrast, Malaria, which is a protozoan-neglected disease, has been known since the 5th century BCE and, despite 2,500 years having passed since then, no human vaccine has yet been licensed for Malaria. Additionally, no modern human vaccine is currently licensed against Visceral or Cutaneous leishmaniasis. Vaccination against Malaria evolved from the inoculation of irradiated sporozoites through the bite of Anopheles mosquitoes in 1930's, which failed to give protection, to the use of controlled human Malaria infection (CHMI) provoked by live sporozoites of Plasmodium falciparum and curtailed with specific chemotherapy since 1940's. Although the use of CHMI for vaccination was relatively efficacious, it has some ethical limitations and was substituted by the use of injected recombinant vaccines expressing the main antigens of the parasite cycle, starting in 1980. Pre-erythrocytic (PEV), Blood stage (BSV), transmission-blocking (TBV), antitoxic (AT), and pregnancy-associated Malaria vaccines are under development. Currently, the RTS,S-PEV vaccine, based on the circumsporozoite protein, is the only one that has arrived at the Phase III trial stage. The "R" stands for the central repeat region of Plasmodium (P.) falciparum circumsporozoite protein (CSP); the "T" for the T-cell epitopes of the CSP; and the "S" for hepatitis B surface antigen (HBsAg). In Africa, this latter vaccine achieved only 36.7% vaccine efficacy (VE) in 5-7 years old children and was associated with an increase in clinical cases in one assay. Therefore, in spite of 35 years of research, there is no currently licensed vaccine against Malaria. In contrast, more progress has been achieved regarding prevention of leishmaniasis by vaccine, which also started with the use of live vaccines. For ethical reasons, these were substituted by second-generation subunit or recombinant DNA and protein vaccines. Currently, there is one live vaccine for humans licensed in Uzbekistan, and four licensed veterinary vaccines against visceral leishmaniasis: Leishmune® (76-80% VE) and CaniLeish® (68.4% VE), which give protection against strong endpoints (severe disease and deaths under natural conditions), and, under less severe endpoints (parasitologically and PCR-positive cases), Leishtec® developed 71.4% VE in a low infective pressure area but only 35.7% VE and transient protection in a high infective pressure area, while Letifend® promoted 72% VE. A human recombinant vaccine based on the Nucleoside hydrolase NH36 of Leishmania (L.) donovani, the main antigen of the Leishmune® vaccine, and the sterol 24-c-methyltransferase (SMT) from L. (L.) infantum has reached the Phase I clinical trial phase but has not yet been licensed against the disease. This review describes the history of vaccine development and is focused on licensed formulations that have been used in preventive medicine. Special attention has been given to the delay in the development and licensing of human vaccines against Protozoan infections, which show high incidence worldwide and still remain severe threats to Public Health.

Association of HPV genotypes with external anogenital warts: a cross sectional study

BACKGROUND

This study was undertaken to determine the distribution of type-specific human papillomavirus (HPV) in external anogenital warts, and the correlation with clinical presentation of warts and demographic data of patients.

METHODS

Genital warts specimens were obtained from 129 men and 27 women attending a dermatology clinic, who had been advised surgical excision. The tissues were fixed and screened for HPV DNA by using real-time PCR. HPV genotype was determined by PCR-based sequencing.

RESULTS

Sixteen different HPV genotypes were detected, comprising 4 oncogenic HPV genotypes (16, 18, 33, 38), 2 low-risk HPV types (LR) (6, 81), HPV 9, and other types associated with common warts (1a, 2, 4, 7, 27b, 27, 57b, 57c, 65). Oncogenic HPV types were found in 34.62% of patients, LR HPV types in 14.4%, HPV 9 in 0.64%, and common warts type in 50.6%. The prevalence of HPV infection with a single type was 88.4, 9.0% for two types, and 2.6% for three types. Multiple logistic regression model showed that age, gender, nationality, number of warts, size of each wart, and positive history of wart in sexual partner, were not predictors of HPV type. However, patients with anogenital warts of one to six months duration were three times more likely to have oncogenic HPV infection compared to those with less than one month.

CONCLUSIONS

This study shows that oncogenic HPV types are detected in around 35% of patients with genital warts, and are prevalent in warts of one to six months duration.

Parental perceptions of human papillomavirus vaccination in central China: the moderating role of socioeconomic factors

Background: The huge gap in adolescent human papillomavirus (HPV) uptake between China (< 2%) and developed countries (> 60%) indicates the necessity of comprehensive examination on the modifiable factors for parents' decision-making. The present study investigated parental perceptions of HPV vaccination for children in China from a socio-economic perspective. Methods: Parents of 9-to-14-year-old adolescents who understood the HPV vaccination (n = 925) completed our questionnaire survey in Fall 2017. Based on the structural equation modeling, we examined the relationship among knowledge, awareness, and intentions of 20 items by 7-point Likert scale, the moderating effects also were tested among 5 socioeconomic variables. Results: Parents of female students have more positive intention about the HPV vaccination than male students' parents (3.74 vs 2.80, p < 0.001). Parents of 12-14-years old students have higher average scores in knowledge (p = 0.006) and intention (p < 0.001) than that of 9-11-years old students' parents. The average score of mothers on knowledge (p = 0.018) and awareness (p < 0.001) was lower than that of fathers. The elder parents (≥ 50 years) performed significantly better on knowledge (p < 0.001) and awareness (p < 0.001) than the other two subgroups. Annual household income is an important factor in determining the knowledge (p = 0.0017), awareness (p < 0.001), and intention (p < 0.001). Knowledge and awareness were considered as the positive determinant of intention, and awareness was partial mediator. Child gender (P = 0.046), child age (P = 0.004), parent gender (P = 0.043) and parental age (P = 0.021) were significant moderators. Conclusion: To improve the acceptability of HPV vaccination among Chinese adolescents, policymakers should develop positive strategies for their parents.

Epithelial boost enhances antigen expression by vaccinia virus for the generation of potent CD8+ T cell-mediated antitumor immunity following DNA priming vaccination

While both pNGVL4a-Sig/E7(detox)/HSP70 DNA vaccine and TA-HPV recombinant vaccinia viral vector-based vaccines have elicited HPV-specific CD8+ T cell responses in HPV16/E7-expressing tumor models, and been used as prime-boost regimen to enhance HPV-specific immune responses in humans (NCT00788164), the optimal route of administration for TA-HPV remains unclear. In a preclinical model, we examined the immunogenicity of priming with intramuscular pNGVL4a-Sig/E7(detox)/HSP70 followed by TA-HPV boost through different administration routes. We observed that priming twice with a pNGVL4a-Sig/E7(detox)/HSP70 followed by a single TA-HPV immunization boost through skin scarification generated the strongest antigen-specific CD8+ T cell response in C57BL/6 mice. These data translate to tumor control and prolonged survival of treated mice. Our results provide rationale for future clinical testing of intramuscular pNGVL4a-Sig/E7(detox)/HSP70 DNA vaccine prime, TA-HPV vaccine skin scarification boost immunization regimen for the control of HPV-associated diseases.

Expanded strain coverage for a highly successful public health tool: Prophylactic 9-valent human papillomavirus vaccine

Human papillomavirus is considered the causative factor for cervical cancer, which accounts for approximately 5% of the global cancer burden and more than 600,000 new cases annually that are attributable to HPV infection worldwide. The first-generation prophylactic HPV vaccines, Gardasil® and Cervarix®, were licensed approximately a decade ago. Both vaccines contain the most prevalent high-risk types, HPV16 and 18, which are associated with 70% of cervical cancer. To further increase the type coverage, 5 additional oncogenic HPV types (31, 33, 45, 52 and 58) were added to the existing Gardasil-4 to develop a 9-valent HPV vaccine (9vHPV), Gardasil 9®, increasing the potential level of protection from ∼70% to ∼90%. The efficacy of the vaccine lies primarily in its ability to elicit type-specific and neutralizing antibodies to fend off the viral infection. Therefore, type-specific and neutralizing murine monoclonal antibodies (mAbs) were used to quantitate the antigenicity of the individual vaccine antigens and to measure the antibody levels in the serum samples from vaccinees in a type- and epitope-specific manner in a competitive immunoassay. Assays for 9vHPV are extended from the proven platform used for 4vHPV by developing and adding new mAbs against the additional types. In Phase III clinical trials, comparable safety profile and immunogenicity against the original 4 types were demonstrated for the 9vHPV vaccine, and these were comparable to the 4vHPV vaccine. The efficacy of the 9vHPV vaccine was established in trials with young women. Immunobridging for younger boys and girls was performed, and the results showed higher immunogenicity in the younger age group. In a subsequent clinical trial, the 2-dose regimen of the 9vHPV vaccine used among girls and boys aged 9-14 y showed non-inferior immunogenicity to the regular 3-dose regimen for young women (aged 16-26 years). Overall, the clinical data and cost-effectiveness analysis for the 9vHPV vaccine support its widespread use to maximize the impact of this important, life-saving vaccine.

Enhancing antitumor immunogenicity of HPV16-E7 DNA vaccine by fusing DNA encoding E7-antigenic peptide to DNA encoding capsid protein L1 of Bovine papillomavirus

Background

Human papillomavirus (HPV) has been identified as the primary etiologic factor of cervical cancer, the fourth leading cause of cancer death in females worldwide. We have previously shown that coadministration of DNA encoding L1 capsid protein of Bovine papillomavirus (BPV) can enhance the antigen-specific immune response elicited by a therapeutic HPV16-E7 DNA vaccination. In this study, we sought to generate and evaluate the immunogenicity of a therapeutic HPV16-E7 DNA vaccine that encodes the fusion construct of HPV16-E7 and BPV-L1.

Results

We generated a therapeutic HPV16-E7 DNA vaccine construct, pcDNA3-BPVL1-E7(49-57), encoding the fusion sequence of full-length BPVL1 protein and a murine E7 antigenic epitope, aa49-57. Transfecting 293-D^b cells with pcDNA3-BPVL1-E7(49-57) demonstrated that this DNA construct can effectively lead to the presentation of E7 epitope for the activation of E7-specific CD8+ T cells in vitro. Intramuscular vaccination of pcDNA3-BPVL1-E7(49-57) with electroporation generated a stronger E7-specific CD8+ T cell-mediated immune response than coadministration of pcDNA3-BPVL1 and pcDNA3-E7(49-57) in C57BL/6 mice. Furthermore, we observed that the strong E7-specific CD8+ T cell response elicited by pcDNA3-BPVL1-E7(49-57) vaccination translated into potent protective and therapeutic antitumor effects in C57BL/6 mice against HPV16-E7 expressing TC-1 tumor cells. Finally, using antibody depletion experiment, we showed that the antitumor immune response generated by pcDNA3-BPVL1-E7(49-57) is CD8+ T cell dependent, and CD4+ T cell and NK cell independent.

Conclusion

Treatment with fusion construct of BPV-L1 and HPV16-E7 epitope can elicit effective E7-specific antitumor immune response in mice. Due to the potential ability of the fusion DNA construct to also trigger immune responses specific to the L1 protein, the current study serves to support future design of HPV DNA vaccines encoding fusion HPVL1-E6/E7 constructs for the generation of both T cell and B cell mediated immune responses against HPV infections and associated diseases.