Epidemiology, clinical manifestations, and recent advances in vaccination against human papillomavirus

Human Papilloma Virus Frequency and Genotypes; Evaluation of the 4879 Screenings Made with Polymerase Chain Reaction and Chip Array Between 2001 and 2019 in Istanbul

Objectives:

The aim of this study is the documentation of human papilloma virus (HPV) frequency and types seen in the city of Istanbul, Turkey, as well as evaluation of the relationship between these subtypes and cytological and pathological diagnoses.

Methods:

4879 cases were studied in our molecular pathology department between 2001 and 2019 in Istanbul. Between 2001 and 2010, 1692 cases were screened for HPV 6, 11, 16, 18, 31, and 33 by conventional hybridization and polymerase chain reaction (PCR). Since 2011, up to 49 HPV typing has been performed for 3187 cases with chip array. The cases were referred to the pathology center and the hospital pathology department by clinicians for screening before HPV vaccination and on the observation of precancerous changes and koilocyts in cytological-histopathological evaluations.

Results:

In this study, the frequency of HPV was found to be 10.8% (527 HPV-positive cases). Among these, 348 cases were high-risk groups, whether or not they were previously associated with a low-risk group. When we look at the distribution of the cases according to the high-risk HPV types, HPV 16 is the most common type. The frequencies of occurrence of other HPV types are as following: HPV–16: 41.7%, HPV–31: 11.7%, HPV–52: 7.9%, HPV–51: 7.1%, HPV–33: 6.9%, HPV–45: 6.5%, HPV–18: 6.3%, HPV–39: 6.1%, and HPV–58: 5.8%. It was further found that multiple infections were 28% of high grade squamous intraepithelial lesion cases. HPV frequency was 38% and 72%, respectively, in cases with cytologically or histopathological precancerous, low-grade squamous intraepithelial lesion, and HSIL changes. As a final note, HPV was detected in 9 of 10 cases with cervical cancer (90%). Only 1 adenocarcinoma case detected in the series was a double infection with HPV types 18 and 45.

Conclusion:

HPV 16 was the most common type found in this study. It is followed by types 31, 52, 51, 33, 45, 18, 39, and 58, respectively. The most common association observed in double infections was between HPV 16 and 58. It was also observed that the incidence of HPV in the city of Istanbul, Turkey, was similar to other developed countries. As a final note, in addition to screening tests, PCR and chip array studies should be conducted and the community should be informed about preventive medicine and the importance of condom use.

[HPV vaccination and the prevention of genital warts and precancerous lesions-current evidence and evaluation]

Human papillomaviruses (HPVs) can cause both benign and malignant tumors. To date, more than 200 HPV types have been discovered, of which 12 are currently classified as high risk for cervical cancer. HPV types that affect the anogenital tract are sexually transmitted. Since 2006, prophylactic HPV vaccines have been available and should be administered before first sexual contact.HPVs infect epithelial cells and are worldwide the most common sexually transmitted viruses. Apart from cervical cancer, HPVs cause other anogenital cancers such as vulvar, vaginal, and anal cancer but also oropharyngeal cancer (or head and neck cancers). HPV types 16 and 18 are also found at these sites. HPV types 6 and 11 are associated with genital warts; other HPV types can cause harmless skin warts.HPV vaccines are safe and highly effective, if they are administered before exposure to HPV. Systematic reviews and meta-analyses have shown that HPV vaccination effectively prevents HPV infection, but also precancerous lesions of the anogenital tract and genital warts. Recent vaccination data also demonstrate reductions in cervical cancer incidence.The uptake rates of HPV vaccination vary worldwide by program and acceptance. In comparison to other European countries, Germany has a low uptake rate. The Standing Committee on Vaccination (STIKO) recommends HPV vaccinations for all girls and boys ages 9 to 14 years in Germany. In 2018, only half of all 18-year-old girls in Germany were completely immunized against HPV.Organized vaccination programs, whether population-based or school-based, are necessary in order to increase vaccination uptake rates.

Functional characterization of CD4 and CD8 T cell responses among human papillomavirus infected patients with ano-genital warts

Ano-genital warts are considered one of the commonest and highly infectious sexually transmitted infections. These warts are primarily caused by the human papillomavirus (HPV) of the family Papillomaviridae, genus alpha-papillomavirus, species 10 and types 6 and 11. However the high recurrence rate of warts is a matter of serious concern to the patients and a challenge for the treating physician. The conventional treatment options are targeted only to the local site of warts. There is no systemic treatment modality as there is limited understanding of the disease immune-pathogenesis. The role of cell-mediated immunity in combating HPV infection is not clearly defined. Hence the present study is aimed at investigating the CD4⁺ T helper (Th1 and Th2) and CD8⁺ T cell responses among wart patients. In this study, we compared HPV6 and HPV11 antigen-specific T cell responses among venereal wart patients relative to healthy controls. Significant decrease in percent frequencies of IFN-γ producing CD4⁺ and CD8⁺ T cells were observed in HPV infected wart patients. On the other hand, the frequency of CD4⁺ T cells expressing IL-4 was significantly increased in these patients as compared to healthy controls. The observed functional skewing of HPV specific T cells from Th1 to Th2 response in patients indicated suppressed immunity against the HPV. Moreover, decrease in CD8 T cell function correlated with poor wart clearance. Our findings open future avenues for exploring potential immunomodulation strategies as an adjunct to standard treatment for better management of these patients and prevention of recurrence.

Human papillomavirus vaccines and cervical cancer: awareness, knowledge, and risk perception among Turkish undergraduate students

The aim of this study was to evaluate awareness, knowledge, and risk perception about human papillomavirus (HPV), cervical cancer, and HPV vaccines among undergraduate students in Turkey. The convenience sample of this descriptive cross-sectional study consisted of 605 undergraduate students in Istanbul University during a semester. Demographic characteristics of students, their reproductive health and lifestyle behaviors, and knowledge of HPV and HPV vaccine were questioned using self-administered forms. The overall proportion of students who had heard about HPV infection was 48.8%, while the proportion of students who had heard of the HPV vaccine was 44.5%. Forty eight percent of females and 60% of males reported never having heard of the HPV. Only 45.7% of females had knowledge about HPV as a cause of genital warts, and 58.1% correctly indicated that HPV caused cervical cancer. The majority of students in both genders (>80%) knew that the infection is primarily transmitted through sexual intercourse. Females were more concerned than males about having cervical/penile cancer associated with HPV in the future. Only 46.4% of females and 39% of males reported having heard of the HPV vaccine. The majority of the female and male students did not know who should get the HPV vaccine and when to get vaccinated. Among males, 25.8% reported that they would consider getting vaccinated (if available) and 38.4% intended to vaccinate their children. Turkish undergraduate students had a low to moderate level of knowledge regarding HPV infection and HPV vaccine. In order to increase awareness about HPV and develop positive behaviors, young people should be provided with accurate information through educational activities in the community and health care services.

Prevalence of human papillomavirus genotypes associated with cervical and breast cancers in iran

Cancer is a multi-step disease, and infection with a DNA virus could play a role in one or more of the steps in this pathogenic process. High-risk human papillomaviruses (HPV) are the causative agent of several cancers. In this study, we determined the prevalence and genotype distribution of HPV infection among Iranian patients with cervix lesions (CL) and breast cancer (BC). The study group consisted of postoperative tissues from patients diagnosed with cervix lesions and breast cancer. We analyzed 250 formalin-fixed, paraffin-embedded tissue blocks from 100 cervix lesions and 150 breast cancer samples. Verification of each cancer reported in a relative was sought through the pathology reports of the hospital records. Cervix lesions were collected from 100 patients with squamous metaplasia (SM, n=50), cervical intraepithelial neoplasia (CINI, n=18, CINII or III, n=8), and cervical carcinoma (CC, n=24). In this study we evaluated the prevalence of HPV by multiplex PCR in cervix lesions and breast cancer. For paraffin-embedded tissues, DNA extracted by the simple boiling method yielded higher proportions of successful gene amplification (99%) for b-actin gene. Overall prevalence of HPV infection was 6% in the SM group, 34.61% in the CIN group, 75% in the CC group, and 34.66% in the BC group. Furthermore, MY09/11 consensus PCR failed to detect 44 (55.69%) of all HPV infections and interestingly, the predominant genotype detected in all cancers was the oncogenic variant HPV16/18; about 34% of women aged 24 to 54 were infected with at least one type of HPV. Our results demonstrate that DNA derived from archival tissues that archived for less than 8 years could be used successfully for HPV genotyping by multiplex PCR. Infection with HPV was prevalent among Iranian women with CC and BC. The results indicate a likely causal role for high-risk HPV in CC and BC, and also offer the possibility of primary prevention of these cancers by vaccination against HPV in Iran.

Comparative Immunogenicity of Evolved V1V2-Deleted HIV-1 Envelope Glycoprotein Trimers

Despite almost 30 years of research, no effective vaccine has yet been developed against HIV-1. Probably such a vaccine would need to induce both an effective T cell and antibody response. Any vaccine component focused on inducing humoral immunity requires the HIV-1 envelope (Env) glycoprotein complex as it is the only viral protein exposed on the virion surface. HIV-1 has evolved several mechanisms to evade broadly reactive neutralizing antibodies. One such a mechanism involves variable loop domains, which are highly flexible structures that shield the underlying conserved epitopes. We hypothesized that removal of such loops would increase the exposure and immunogenicity of these conserved regions. Env variable loop deletion however often leads to protein misfolding and aggregation because hydrophobic patches becoming solvent accessible. We have therefore previously used virus evolution to acquire functional Env proteins lacking the V1V2 loop. We then expressed them in soluble (uncleaved) gp140 forms. Three mutants were found to perform optimally in terms of protein expression, stability, trimerization and folding. In this study, we characterized the immune responses to these antigens in rabbits. The V1V2 deletion mutant ΔV1V2.9.VK induced a prominent response directed to epitopes that are not fully available on the other Env proteins tested but that effectively bound and neutralized the ΔV1V2 Env virus. This Env variant also induced more efficient neutralization of the tier 1 virus SF162. The immune refocusing effect was lost after booster immunization with a full-length gp140 protein with intact V1V2 loops. Collectively, this result suggests that deletion of variable domains could alter the specificity of the humoral immune response, but did not result in broad neutralization of neutralization-resistant virus isolates.

Lassa virus-like particles displaying all major immunological determinants as a vaccine candidate for Lassa hemorrhagic fever

BACKGROUND

Lassa fever is a neglected tropical disease with significant impact on the health care system, society, and economy of Western and Central African nations where it is endemic. Treatment of acute Lassa fever infections has successfully utilized intravenous administration of ribavirin, a nucleotide analogue drug, but this is not an approved use; efficacy of oral administration has not been demonstrated. To date, several potential new vaccine platforms have been explored, but none have progressed toward clinical trials and commercialization. Therefore, the development of a robust vaccine platform that could be generated in sufficient quantities and at a low cost per dose could herald a subcontinent-wide vaccination program. This would move Lassa endemic areas toward the control and reduction of major outbreaks and endemic infections. To this end, we have employed efficient mammalian expression systems to generate a Lassa virus (LASV)-like particle (VLP)-based modular vaccine platform.

RESULTS

A mammalian expression system that generated large quantities of LASV VLP in human cells at small scale settings was developed. These VLP contained the major immunological determinants of the virus: glycoprotein complex, nucleoprotein, and Z matrix protein, with known post-translational modifications. The viral proteins packaged into LASV VLP were characterized, including glycosylation profiles of glycoprotein subunits GP1 and GP2, and structural compartmentalization of each polypeptide. The host cell protein component of LASV VLP was also partially analyzed, namely glycoprotein incorporation, though the identity of these proteins remain unknown. All combinations of LASV Z, GPC, and NP proteins that generated VLP did not incorporate host cell ribosomes, a known component of native arenaviral particles, despite detection of small RNA species packaged into pseudoparticles. Although VLP did not contain the same host cell components as the native virion, electron microscopy analysis demonstrated that LASV VLP appeared structurally similar to native virions, with pleiomorphic distribution in size and shape. LASV VLP that displayed GPC or GPC+NP were immunogenic in mice, and generated a significant IgG response to individual viral proteins over the course of three immunizations, in the absence of adjuvants. Furthermore, sera from convalescent Lassa fever patients recognized VLP in ELISA format, thus affirming the presence of native epitopes displayed by the recombinant pseudoparticles.

CONCLUSIONS

These results established that modular LASV VLP can be generated displaying high levels of immunogenic viral proteins, and that small laboratory scale mammalian expression systems are capable of producing multi-milligram quantities of pseudoparticles. These VLP are structurally and morphologically similar to native LASV virions, but lack replicative functions, and thus can be safely generated in low biosafety level settings. LASV VLP were immunogenic in mice in the absence of adjuvants, with mature IgG responses developing within a few weeks after the first immunization. These studies highlight the relevance of a VLP platform for designing an optimal vaccine candidate against Lassa hemorrhagic fever, and warrant further investigation in lethal challenge animal models to establish their protective potential.

Proteomics and the search for biomarkers of female reproductive diseases

Over the past decade, high-throughput proteomics technologies have evolved considerably and have become increasingly more commonly applied to the investigation of female reproductive diseases. Proteomic approaches facilitate the identification of new disease biomarkers by comparing the abundance of hundreds of proteins simultaneously to find those specific to a particular clinical condition. Some of the best studied areas of female reproductive biology applying proteomics include gynaecological cancers, endometriosis and endometrial infertility. This review will discuss the progress that has been made in these areas and will highlight some of the emerging technologies that promise to contribute to better understanding of the female reproductive disease.

Vacina contra o papilomavirus humano. O que é preciso saber?

As vacinas contra o Papilomavirus Humano (HPV) já estão disponíveis para consumo. Temos dois tipos: a bivalente, que determina imunidade contra os tipos oncogênicos 16 e 18, os mais relacionados com os carcinomas anogenitais e da orofaringe, a quadrivalente, que além desses, imuniza contra os tipos 6 e 11, que provocam as verrugas anogenitais. Estão mais indicadas para mulheres dos 10 aos 25 anos, antes do início da vida sexual ou naquelas que não tiveram contato com os tipos virais envolvidos. As vacinas não têm efeito em quem já possui lesões provocadas pelos tipos virais imunizáveis. Podem ser usadas nas imunodeprimidas por qualquer causa, naquelas que estão amamentando, mas são contra-indicadas durante a gravidez. O uso em homens, guardando as mesmas indicações, foi liberado pelo FDA (Food and Drugs Administration) norte-americano, porém ainda não pela ANVISA (Agência Nacional de Vigilância Sanitária), o correspondente brasileiro. Para aqueles que já estão contaminados pelos tipos virais envolvidos, resta esperar pela vacina terapêutica que permanece em avaliação com ensaios clínicos.