Natural History of Human Papillomavirus Type 16 Virus-Like Particle Antibodies in Young Women

Serologic Response to Human Papillomavirus Genotypes Among Unvaccinated Women: Findings From the HITCH Cohort Study

BACKGROUND

Humoral immune responses may be critical for preventing, controlling, and/or eliminating human papillomavirus (HPV) infection. We analyzed humoral response to natural HPV infection considering phylogenetic relatedness among unvaccinated women.

METHODS

We included 399 young women attending university/college in Montreal, Canada who were participants of the HITCH cohort. Participants provided blood samples at baseline and 5 follow-up visits. Antibody response to bacterially expressed L1 and E6 glutathione S-transferase (GST) fusion proteins, and virus-like particles (VLP-L1) of Alphapapillomavirus types were measured using multiplex serology. We assessed correlations and associations between HPV types at baseline using Pearson correlation coefficients (r) and univariable linear regressions.

RESULTS

At baseline, > 40% were seropositive for GST-L1 antibodies of at least 1 HPV type. Strong correlations between GST-L1 were observed for α9 HPV types: 58-52 (r = 0.86), 58-33 (r = 0.75), 33-52 (r = 0.72), and between GST-E6: 52-11 (r = 0.84), 52-18 (r = 0.79), 58-33 (r = 0.78), 35-11 (r = 0.76). HPV16 VLP-L1 moderately explained variability in HPV16 GST-L1 (regression coefficient [b] = 0.38, R2 = 43.1%), and HPV45 GST-L1 in HPV18 GST-L1 (b = 0.68, R2 = 42.8%). GST-E6 antibodies accounted for a low to moderate proportion of variability in HPV16 and HPV18 GST-E6 (R2 = 6.4%-62.2%).

CONCLUSIONS

Associations between naturally induced HPV-specific antibodies depend on phylogenetic relatedness.

Immunity after HPV Vaccination in Patients after Sexual Initiation

Vaccinations against human papillomavirus (HPV) are included in the primary prevention of precancerous intraepithelial lesions and HPV-related cancers. Despite the undeniable effectiveness of vaccination in the juvenile population, there is still little research on the effect in patients after sexual initiation. Our study aims to assess anti-HPV (L1 HPV) antibodies in healthy patients and diagnosed cervical pathology after 9-valent vaccination. We provide a prospective, ongoing 12-month, non-randomised pilot study in which 89 subjects were enrolled. We used an enzyme-linked immunosorbent assay to determine IgG class antibodies to HPV. We noted significantly higher levels of antibodies in vaccinated individuals than in the unvaccinated control group. The above work shows that vaccination against HPV might be beneficial in patients after sexual initiation as well as in those already diagnosed with HPV or SIL infection.

Human papillomavirus seroprevalence and seroconversion following baseline detection of nine human papillomavirus types in young women

Background

Estimates of the humoral immune response to incident human papillomavirus (HPV) infections are limited.

Methods

In this post hoc analysis of 3875 women aged 16–23 years from a 4-valent HPV vaccine trial (NCT00092482), HPV seroprevalence on day 1 was measured with a 9-valent HPV (HPV 6/11/16/18/31/33/45/52/58) competitive Luminex immunoassay and compared with cervical/external genital HPV detection by polymerase chain reaction. In the control group, among women who were HPV DNA‒negative on day 1, seroconversion following initial HPV detection was estimated using Kaplan-Meier methods.

Results

Type-specific HPV seropositivity among women with no day 1 cervical/external genital HPV detection was 0.6%–3.6%. Women with any 9-valent HPV (9vHPV) cervical/external genital detection (796/3875; 20.5%) had concordant seropositivity ranging from 13.4% (HPV 45) to 38.5% (HPV 6). Among women in the control group who were negative for all HPV types on day 1, seroconversion by month 30 after initial detection ranged from 29% (HPV 45) to 75% (HPV 16).

Conclusions

Humoral immune response to HPV is variable and dynamic, depending on type-specific exposure. This longitudinal analysis provides insight into the relationship between incident infection and seropositivity.

ClinicalTrials.gov; NCT00092482 https://clinicaltrials.gov/ct2/show/NCT00092482.

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Research on humoral immune responses to HPV infection are limited.

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HPV-related serologic responses were analyzed in women aged 16–23 years.

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Type-specific HPV seropositivity was low in women without initial HPV DNA detection.

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Concordant seropositivity in women with any 9vHPV DNA detection ranged from 13% to 40%.

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Seroconversion to the same genotype within 30 months of an infection was common.

HPV vaccination among seropositive, DNA negative cohorts: a systematic review & meta-analysis

Objective

Vaccine efficacy among previously exposed, but currently uninfected women, i.e., those who have serological evidence of a prior human papillomavirus (HPV) infection without corresponding detectable HPV DNA, remains incompletely defined. This meta-analysis assessed the serotype-specific efficacy of prophylactic HPV vaccination against HPV16/18 persistent infection (PI) and cervical intraepithelial neoplasia (CIN) among seropositive, DNA negative (SPDN) women enrolled to randomized controlled trials (RCTs) of HPV L1-based vaccines.

Methods

Searches were conducted on 08/16/20 on MEDLINE, Embase, Scopus and CENTRAL. RCTs of L1-based prophylactic bivalent or quadrivalent HPV vaccines, reporting serotype-specific clinical efficacy endpoints in the HPV16/18 seropositive, DNA-negative populations were included. Relative risks (RRs) of 6-month PI (6mPI), 12-month PI (12mPI), CIN1+ and CIN2+ were pooled using a random-effects model.

Results

A total of 1,727 citations were reviewed. 8 studies, with a total of 9,569 SPDN participants, met all eligibility criteria. The RR of 6mPI (RR=0.22; 95% confidence interval [CI]=0.08–0.61; p=0.018), 12mPI (RR=0.20; 95% CI=0.05–0.80; p=0.035), CIN1+ (RR=0.13; 95% CI=0.05–0.30; p=0.003) and CIN2+ (RR=0.15; 95% CI=0.04–0.59; p=0.022) was significantly reduced in the vaccinated compared to the unvaccinated group.

Conclusion

Our findings suggest high serotype-specific efficacy for HPV vaccination among cohorts of women with evidence of prior HPV16/18 infections, including 87% efficacy (95% CI=70%–95%; p=0.003) against HPV16/18 cervical dysplasia. HPV vaccination is highly effective among uninfected women, regardless of prior exposure history.

Trial Registration

PROSPERO Identifier: CRD42020206888

Peter L, Studentsov Y, Nucci-Sack A, Diaz A, Pickering S, Schlecht NF, Burk RD. Anti-HPV16 Antibody Titers Prior to an Incident Cervical HPV16/31 Infection

The goal of this study was to investigate the serological titers of circulating antibodies against human papillomavirus (HPV) type 16 (anti-HPV16) prior to the detection of an incident HPV16 or HPV31 infection amongst vaccinated participants. Patients were selected from a prospective post-HPV vaccine longitudinal cohort at Mount Sinai Adolescent Health Center in Manhattan, NY. We performed a nested case-control study of 43 cases with incident detection of cervical HPV16 (n = 26) or HPV31 (n = 17) DNA who had completed the full set of immunizations of the quadrivalent HPV vaccine (4vHPV). Two control individuals whom had received three doses of the vaccine (HPV16/31-negative) were selected per case, matched on age at the first dose of vaccination and follow-up time in the study: a random control, and a high-risk control that was in the upper quartile of a sexual risk behavior score. We conducted an enzyme-linked immunosorbent assay (ELISA) for the detection of immunoglobulin G (IgG) antibodies specific to anti-HPV16 virus-like particles (VLPs). The results suggest that the average log antibody titers were higher among high-risk controls than the HPV16/31 incident cases and the randomly selected controls. We show a prospective association between anti-HPV16 VLP titers and the acquisition of an HPV16/31 incident infection post-receiving three doses of 4vHPV vaccine.

Tumor microenvironment: an evil nexus promoting aggressive head and neck squamous cell carcinoma and avenue for targeted therapy

Head and neck squamous cell carcinoma (HNSCC) is a very aggressive disease with a poor prognosis for advanced-stage tumors. Recent clinical, genomic, and cellular studies have revealed the highly heterogeneous and immunosuppressive nature of HNSCC. Despite significant advances in multimodal therapeutic interventions, failure to cure and recurrence are common and account for most deaths. It is becoming increasingly apparent that tumor microenvironment (TME) plays a critical role in HNSCC tumorigenesis, promotes the evolution of aggressive tumors and resistance to therapy, and thereby adversely affects the prognosis. A complete understanding of the TME factors, together with the highly complex tumor-stromal interactions, can lead to new therapeutic interventions in HNSCC. Interestingly, different molecular and immune landscapes between HPV^+ve and HPV^-ve (human papillomavirus) HNSCC tumors offer new opportunities for developing individualized, targeted chemoimmunotherapy (CIT) regimen. This review highlights the current understanding of the complexity between HPV^+ve and HPV^-ve HNSCC TME and various tumor-stromal cross-talk modulating processes, including epithelial-mesenchymal transition (EMT), anoikis resistance, angiogenesis, immune surveillance, metastatic niche, therapeutic resistance, and development of an aggressive tumor phenotype. Furthermore, we summarize the recent developments and the rationale behind CIT strategies and their clinical applications in HPV^+ve and HPV^-ve HNSCC.

Seroprevalence of Human Papillomavirus 6/11/16/18 Among Self-identified Gay/Bisexual Men Who Have Sex With Men, Men Who Have Sex With Women, and Females, United States, 2003-2010

BACKGROUND

Differences in human papillomavirus (HPV) seroprevalence by sex have been observed, likely due to differences in the anatomic site of HPV exposure. Seroconversion may be more likely after exposure at nonkeratinized (mucosal) compared to keratinized epithelium. We compared seroprevalence among self-identified gay/bisexual men who have sex with men (MSM) and females, 2 groups more likely exposed at mucosal epithelium, and men who only have sex with women (MSW), a group likely exposed primarily at keratinized epithelium, using data from the National Health and Nutrition Examination Survey from 2003 to 2010.

METHODS

HPV 6/11/16/18 serum antibody was detected using a multiplexed, competitive luminex immunoassay. Weighted seroprevalence was estimated among unvaccinated, sexually experienced 18-59 year-old MSM, MSW, and females, overall and by demographic and sexual behavior characteristics. Seroprevalences were compared using prevalence ratios adjusted for sexual behavior (aPRs).

RESULTS

Overall, seroprevalence in MSM, MSW, and females was 42.6%, 13.2%, and 37.1%, respectively. Seroprevalence in MSM was comparable to females (aPR: 0.85, 95% confidence interval [CI]: 0.68-1.08) and higher than MSW (aPR: 2.72, 95% CI: 2.19-3.38). MSW had a significantly lower seroprevalence than females (aPR: 0.31, 95% CI: 0.28-0.34). Similar associations were seen in all sociodemographic subgroups. Seroprevalence increased with number of lifetime sex partners in all groups.

CONCLUSIONS

In this population-based survey, HPV seroprevalence among groups likely exposed at mucosal epithelium (MSM, females) was comparable; seroprevalence in both groups was higher than in MSW. Future research could explore whether differences in seropositivity following infection result in differential protection from future infection.

Insights into the Role of Innate Immunity in Cervicovaginal Papillomavirus Infection from Studies Using Gene-Deficient Mice

We demonstrate that female C57BL/6J mice are susceptible to a transient lower genital tract infection with MmuPV1 mouse papillomavirus and display focal histopathological abnormalities resembling those of human papillomavirus (HPV) infection. We took advantage of strains of genetically deficient mice to study in vivo the role of innate immune signaling in the control of papillomavirus. At 4 months, we sacrificed MmuPV1-infected mice and measured viral 757/3139 spliced transcripts by TaqMan reverse transcription-PCR (RT-PCR), localization of infection by RNAscope in situ hybridization, and histopathological abnormities by hematoxylin and eosin (H&E) staining. Among mice deficient in receptors for pathogen-associated molecular patterns, MyD88^-/- and STING^-/- mice had 1,350 and 80 copies of spliced transcripts/μg RNA, respectively, while no viral expression was detected in MAVS^-/- and Ripk2^-/- mice. Mice deficient in an adaptor molecule, STAT1^-/-, for interferon signaling had 46,000 copies/μg RNA. Among mice with targeted deficiencies in the inflammatory response, interleukin-1 receptor knockout (IL-1R^-/-) and caspase-1^-/- mice had 350 and 30 copies/μg RNA, respectively. Among mice deficient in chemokine receptors, CCR6^-/- mice had 120 copies/μg RNA, while CXCR2^-/- and CXCR3^-/- mice were negative. RNAscope confirmed focal infection in MyD88^-/-, STAT1^-/-, and CCR6^-/- mice but was negative for other gene-deficient mice. Histological abnormalities were seen only in the latter mice. Our findings and the literature support a working model of innate immunity to papillomaviruses involving the activation of a MyD88-dependent pathway and IL-1 receptor signaling, control of viral replication by interferon-stimulated genes, and clearance of virus-transformed dysplastic cells by the action of the CCR6/CCL20 axis.IMPORTANCE Papillomaviruses infect stratified squamous epithelia, and the viral life cycle is linked to epithelial differentiation. Additionally, changes occur in viral and host gene expression, and immune cells are activated to modulate the infectious process. In vitro studies with keratinocytes cannot fully model the complex viral and host responses and do not reflect the contribution of local and migrating immune cells. We show that female C57BL/6J mice are susceptible to a transient papillomavirus cervicovaginal infection, and mice deficient in select genes involved in innate immune responses are susceptible to persistent infection with variable manifestations of histopathological abnormalities. The results of our studies support a working model of innate immunity to papillomaviruses, and the model provides a framework for more in-depth studies. A better understanding of mechanisms of early viral clearance and the development of approaches to induce clearance will be important for cancer prevention and the treatment of HPV-related diseases.

Integrating measures of viral prevalence and seroprevalence: a mechanistic modelling approach to explaining cohort patterns of human papillomavirus in women in the USA

Incidence of human papillomavirus (HPV) related cancers is increasing, generating substantial interest in understanding how trends in population prevalence of HPV infection are changing. However, there are no direct, population-scale measurements of HPV prevalence prior to 2003. Previous work using models to reconstruct historical trends have focused only on genital infection or seroprevalence (prevalence of antibodies) separately, and the results of these single-measure studies have been hard to reconcile. Here, we develop a mechanistic disease model fit jointly to cervicogential prevalence and seroprevalence in unvaccinated women in the USA using National Health and Nutrition Examination Survey data (2003-2010) and compare it to fits of statistical age-cohort models. We find that including a latent HPV state in our model significantly improves model fit and that antibody waning may be an important contributor to observed patterns of seroprevalence. Moreover, we find that the mechanistic model outperforms the statistical model and that the joint analysis prevents the inconsistencies that arise when estimating historical cohort trends in infection from genital prevalence and seroprevalence separately. Our analysis suggests that while there is substantial uncertainty associated with the estimation of historic HPV trends, there has likely been an increase in the force of infection for more recent birth cohorts. This article is part of the theme issue 'Silent cancer agents: multi-disciplinary modelling of human DNA oncoviruses'.

HPV-Specific Systemic Antibody Responses and Memory B Cells are Independently Maintained up to 6 Years and in a Vaccine-Specific Manner Following Immunization with Cervarix and Gardasil in Adolescent and Young Adult Women in Vaccination Programs in Italy

Human papillomavirus (HPV) persistent infections are associated with cervical cancer and other HPV-related diseases and tumors. Thus, the characterization of long lasting immunity to currently available HPV vaccines is important. A total of 149 female subjects vaccinated with Cervarix or Gardasil participated to the study and they were stratified according to age (10–12-year-old and 16–20-year-old). Humoral immune responses (IgG and neutralizing antibody titers, antibody avidity) and circulating memory B cells were analyzed after an average of 4–6 years from the third immunization. The humoral responses against HPV-16 and HPV-18 (and HPV-6 and HPV-11 for Gardasil) were high in both age groups and vaccines up to six years from the third dose. However, Cervarix induced significantly higher and more persistent antibody responses, while the two vaccines were rather equivalent in inducing memory B cells against HPV-16 and HPV-18. Moreover, the percentage of subjects with vaccine-specific memory B cells was even superior among Gardasil vaccinees and, conversely, Cervarix vaccinated individuals with circulating antibodies, but undetectable memory B cells were found. Finally, a higher proportion of Cervarix-vaccinated subjects displayed cross-neutralizing responses against non-vaccine types HPV-31 and HPV-45. Gardasil and Cervarix may, thus, differently affect long-lasting humoral immunity from both the quantitative and qualitative point of view.

Seropositivity to Multiple Anogenital Human Papillomavirus (HPV) Types Is Associated With Current Anogenital HPV Infection, Abnormal Cytology, and Seropositivity for Nongenital HPVs

Background

Antibodies against human papillomaviruses (HPVs) are biomarkers for current or past infections. We assessed whether antibodies against multiple HPV types were determinants of current multiple anogenital HPV infections, abnormal cytology, and seropositivity for cutaneous HPVs.

Methods

A total of 1848 Slovenian women attended 2 rounds of cervical cancer screening 3 years apart and provided data on HPV antibodies and HPV DNA at both visits. Antibodies against 15 anogenital HPV types and 6 cutaneous HPVs were determined using pseudovirion-Luminex serology and anogenital HPV DNA using Linear Array. Antibodies to polyomaviruses were evaluated as a control. Women were grouped as either HPV seronegative or having antibodies to 1-2 HPV types or to ≥3 HPV types.

Results

Presence of antibodies to multiple anogenital HPV types at baseline was associated strongly with (i) presence of HPV DNA at the cervix (χ2 = 68.8; P < .0001), (ii) multiple types of HPV DNA at baseline (χ2 = 58.6; P < .0001), (iii) HPV DNA at follow-up (χ2 = 22.9; P < .0001), (iv) abnormal cytology (χ2 = 9.8; P = .0017), and (v) concomitant presence of antibodies to any of 6 nongenital HPV types (χ2 = 40.1; P < .0001). Presence of antibodies to ≥3 anogenital HPV types tended to persist over time.

Conclusions

Seropositivity against at least 3 anogenital HPV types is associated with current multiple anogenital HPV infections, abnormal cytology, and seropositivity to nongenital HPVs.

Characterization of Immunoglobulin A/G Responses During 3 Doses of the Human Papillomavirus-16/18 ASO4-Adjuvanted Vaccine

BACKGROUND

Individuals receiving the human papillomavirus (HPV) vaccine develop high levels of circulating neutralizing antibodies. However, data about antibody responses in the cervix are limited.

METHODS

This study was designed to describe the course of IgA/IgG responses in cervical secretions and in serum after intramuscular administration of the HPV16/18 AS04-adjuvant vaccine. An enzyme-linked immunosorbent assay for detection of IgA and IgG anti-HPV-VLP was developed for this purpose.

RESULTS

Immunoglobulin G seroconversion after the second dose was observed in 100% of the participants and remained 1 month after the third dose. Regarding IgG reactivity in cervical secretions, conversion was observed in 85% of women after the final dose. Immunoglobulin A seroconversion was observed in 76.7% of women after the third dose. Lower levels of IgA were detected in the cervical mucus (28.3%) and decreased to 23.3% after the last dose. Comparing local and systemic IgG responses, positivity in both serum and cervical samples was observed in 85%, whereas in 15% only, the serum was IgG antibody positive. A weak agreement between local and systemic IgA responses was observed. Only 18.3% of participants were local and systemic IgA positive, 58.4% were positive only in serum, 5% were positive only in the cervix, and 18.3% were both local and systemic IgA antibody negative.

CONCLUSIONS

After the third vaccination, there is a strong agreement between cervical and systemic IgG antibody responses and a weak agreement between cervical and systemic IgA antibody responses. The induction of IgA antibodies seems to be secondary to that of IgG antibodies in response to HPV intramuscular vaccination.

Natural History of HPV Infection across the Lifespan: Role of Viral Latency

Large-scale epidemiologic studies have been invaluable for elaboration of the causal relationship between persistent detection of genital human papillomavirus (HPV) infection and the development of invasive cervical cancer. However, these studies provide limited data to adequately inform models of the individual-level natural history of HPV infection over the course of a lifetime, and particularly ignore the biological distinction between HPV-negative tests and lack of infection (i.e., the possibility of latent, undetectable HPV infection). Using data from more recent epidemiological studies, this review proposes an alternative model of the natural history of genital HPV across the life span. We argue that a more complete elucidation of the age-specific probabilities of the alternative transitions is highly relevant with the expanded use of HPV testing in cervical cancer screening. With routine HPV testing in cervical cancer screening, women commonly transition in and out of HPV detectability, raising concerns for the patient and the provider regarding the source of the positive test result, its prognosis, and effective strategies to prevent future recurrence. Alternative study designs and analytic frameworks are proposed to better understand the frequency and determinants of these transition pathways.

Reactivation of Latent HPV Infections After Renal Transplantation

Female renal transplant recipients (RTRs) have an increased risk for developing human papillomavirus (HPV)-related (pre)malignant lesions of the genital tract. This study aims to assess the genital prevalence of HPV before and after renal transplantation (RT). In female patients who were counseled for RT at the Radboud University Medical Center Nijmegen, the Netherlands, gynecological examination was performed at first visit, and 1 and 2 years later. HPV self-sampling and questionnaires on sexual behavior were performed every 3 months. In 65 patients who underwent RT, the high-risk human papillomavirus (hrHPV) prevalence as assessed with the highly sensitive SPF₁₀ -LiPA₂₅ test increased significantly from 19% before to 31% after RT (p = 0.045). Based upon the clinically validated Cobas 4800 HPV test, the hrHPV prevalence increased from 10% before to 14% after RT (p = 0.31). During follow-up, no changes in sexual behavior were reported. Thirty-three patients who did not undergo RT showed a hrHPV prevalence of 21% at study entry and of 27% after 12 months with the sensitive test, and a stable prevalence of 16% with the clinically validated test. The results of this study indicate that activation of latent HPV infections may contribute to the increased risk of HPV-related (pre)malignant lesions in female RTRs.

Concordance of HPV-DNA in cervical dysplasia or genital warts in women and their monogamous long-term male partners

Transmission of human papillomavirus (HPV) is a premise for development of cervical dysplasia and genital warts (GWs). This cross-sectional study assesses concordance of HPV types present in GWs or cervical dysplasia in women and genital infection of their monogamous male partners in conjunction with seroprevalence of HPV-6, -11, -16, and -18 antibodies. Blood was taken from both women and men, as well a smear of the urogenital area of men. HPV DNA detection in women was done in fixed paraffin embedded tissues under histological control. Of 143 couples who agreed to participate in the study, 68 met inclusion criteria. Type-specific concordance was observed in 32.5% (13/40) of couples in which women had genital warts and in 32.1% (9/28) of couples in which women had cervical dysplasia. In multivariate analysis only smoking in women was associated with concordance (P < 0.05). Prevalence of HPV-specific antibodies was high in male partners, but was not associated with presence of the same HPV type on their genitals. The same type-specific HPV antibodies were detected in 81.8% of men in couples with HPV-6 concordant genital warts, but only in 14.3% of men in couples with HPV-16 concordant cervical dysplasia (P < 0.01). These results suggest that type-specific HPV concordance in genital warts and cervical dysplasia lesions of women and genital infection of their male partners is common and similar. Higher seroconversion in couples with HPV-6 concordant genital warts compared with couples with HPV-16 concordant cervical dysplasia may be explained by viral load exposure.

The prevalence of HPV infections in HPV-vaccinated women from the general population

Currently, three prophylactic HPV vaccines are commercially available to prevent HPV 16/18 infection and associated lesions. The aim of the study was to assess markers of HPV infection in women/girls before vaccination and to ascertain the prevalence and spectrum of post-vaccination HPV types. Three hundred and thirty subjects of which 75 were virgins were enrolled. Before the first dose of the HPV vaccine and 1, 3 and 5 years after the completion of HPV vaccination, the samples for cytology, HPV detection and anti-HPV antibody response were taken. At enrolment, HPV DNA was detected in 38% of sexually active girls/women. At the first, second and third follow-up, HPV DNA was found in 40, 45, and 39% of them. The seroprevalence rates to HPV 6, 11, 16 and 18 in these subjects were 31, 21, 18 and 10%. On the follow-up significantly higher levels of antibodies to HPV 16/18 were found after application of divalent vaccine. Results of the study demonstrate high prevalence of HPV infection in young women. In a substantial number of women, HPV-specific antibodies as well as high-risk HPV types were detected. HPV-specific antibodies were also frequently found in non-sexually active girls. The acquisition of HPV after the onset of sexual life was very fast.

Journey of the Human Papillomavirus (HPV) in a Developing Country over 5 Years (2010 - 2015)

Human papillomavirus (HPV) is a prevalent sexually transmitted infection with serious medical, sexual, and relationship consequences. HPV vaccine protection is available globally but unfortunately vaccine uptake is inconsistent everywhere. From this study, it was observed that the awareness of cervical cancer, HPV virus and HPV vaccination in Malaysia is high, at 83.1%, 73.9% and 73.3% of respondents, respectively. However, a considerably low percentage had undergone HPV vaccination (8.6%) compared to those who had experienced a Pap smear (32.9%). Awareness between cervical cancer and HPV virus and vaccination was low. Health care providers and the governing bodies have to play a vital role in disseminating holistic information on the vaccine and the importance of getting vaccinated to the public more vigorously in Malaysia.

Race is Associated With Sexual Behaviors and Modifies the Effect of Age on Human Papillomavirus Serostatus Among Perimenopausal Women

BACKGROUND

Human papillomavirus (HPV) causes oropharyngeal and cervical cancers. Oropharyngeal cancer primarily affects whites, but cervical cancer is more common among blacks. Reasons for this distinct epidemiology are unclear.

METHODS

Serum was collected from women aged 35 to 60 years in the HPV in Perimenopause cohort and evaluated for antibodies to 8 HPV types. Demographic and behavioral data were collected by telephone questionnaire. Associations between sexual behaviors, race, age, HPV serostatus, and strength of serologic response to HPV were evaluated.

RESULTS

There were 781 women in this analysis, including 620 white (79%) and 161 (21%) black women. Whites were less likely to report 5+ vaginal sex partners (prevalence ratio [PR], 0.86; 95% confidence interval [CI], 0.77-0.97), but more likely to report 5+ oral sex partners (PR, 2.38; 95% CI, 1.62-3.49) compared with blacks. Seropositivity to most individual HPV types and at least 3 types was significantly lower in whites than in blacks (PR, 0.62; 95% CI, 0.47-0.80). Human papillomavirus seropositivity was independently associated with younger age among blacks, but with sexual exposures among whites. Furthermore, strength of serologic response to most HPV types significantly decreased with older age among blacks, but not among whites.

CONCLUSIONS

Racial differences in immune markers of HPV exposure and the epidemiology of HPV-related cancers may be linked to differences in patterns of sexual behaviors.

A cross-sectional study on the concordance between vaginal HPV DNA detection and type-specific antibodies in a multi-ethnic cohort of women from Amsterdam, the Netherlands - the HELIUS study

Background

Acquisition of genital human papillomavirus (HPV) infection is common among the young, sexually active population. Genital HPV infections do not always lead to seroconversion. We aimed to assess the association between cervico-vaginal high risk (hr) HPV DNA and type-specific antibodies in an ethnically diverse cohort of young women.

Methods

Women of Dutch, South-Asian Surinamese, African Surinamese, Ghanaian, Moroccan and Turkish origin participating in a large-scale multi-ethnic population-based cohort (the HELIUS study) provided vaginal self-samples and blood samples, and completed a questionnaire regarding demographics, lifestyle and sexual health. Vaginal swabs were tested for HPV using the highly sensitive SPF10-PCR DEIA/LiPA25 system (version1). Serum samples were tested for type-specific L1 antibodies against 7 hrHPV types (16,18,31,33,45,52,58) with multiplex serology. We assessed the association between vaginal HPV DNA and type-specific seropositivity with logistic and linear regression, using generalized estimating equations (GEE). We determined whether this association varies by ethnicity by adding an interaction term.

Results

We selected 532 women who completed the questionnaire, provided a vaginal swab and a blood sample. Their median age was 27 years (interquartile range 24–31 years). Prevalence of DNA of any of the 7 hrHPV was 22 %; HPV-52 was most common. Prevalence of antibodies against one or more hrHPV types was 24 %; HPV-16 seropositivity was most common. In multivariable logistic regression analysis using GEE, adjusting for other determinants, vaginal HPV DNA detection was associated with type-specific HPV seropositivity (OR 1.53, 95 % CI 1.06-2.20). In multivariable linear regression analysis using GEE, the geometric mean of type-specific antibody reactivity was 1.15 (95 % CI 1.04-1.27) times higher in women positive for HPV DNA compared to HPV DNA-negative women. There was little evidence that ethnicity modified the association between HPV DNA, and type-specific seropositivity, or with antibody reactivities (p = 0.47 and p = 0.57, respectively).

Conclusions

In this multi-ethnic group of young women in Amsterdam, cervico-vaginal hrHPV DNA detection was an independent determinant of type-specific HPV seropositivity.

Re-detection vs. new acquisition of high-risk human papillomavirus in mid-adult women

To understand high-risk (hr) human papillomavirus (HPV) epidemiology in mid-adulthood, we assessed whether associations between incident detection of hrHPV DNA and recent sexual behavior differed according to whether or not there was serologic evidence of prior infection. From 2011 to 2012, we enrolled 409 women aged 30-50 years into a 6-month longitudinal study. We collected health and sexual behavior histories, enrollment sera for HPV antibody testing, and monthly self-collected vaginal swabs for HPV DNA genotyping. Generalized estimating equations logistic regression identified risk factors for type-specific incident hrHPV DNA, stratified by type-specific hrHPV serostatus at enrollment. Population attributable risks of hrHPV due to prior and recent exposure were estimated. When type-specific hrHPV serology was negative, recent sexual risk behavior was positively associated with incident hrHPV DNA (odds ratio in women reporting ≥3 recent sexual risk behaviors [e.g., new or multiple partners] vs. no recent sexual activity = 9.8, 95% CI: 2.4-40.6). No associations with recent sexual behavior were observed with positive type-specific hrHPV serology. Thirty percent of incident hrHPV DNA detection was attributable to prior infection (with positive serology) and 40% was attributable to recent sexual risk behavior (with negative serology). The proportion of incident hrHPV DNA detection attributable to recent sexual risk behavior decreased with increasing age. Among women with serologic evidence of prior infection, re-detection of the same hrHPV type is likely due to reactivation or intermittent detection of persistent infection. Without serologic evidence of prior infection, new detection is likely due to new acquisition or to intermittent detection of persisting infection.

A Serological Epidemiological Survey of Antibodies against 4 HPV Subtypes in Uygur Women in Xinjiang

This study evaluated the distribution of antibodies against 4 human papillomavirus (HPV) subtypes and their related factors among Uygur women in Xinjiang. A cross-sectional study was conducted from March 2006 to May 2007 involving 883 Uygur women aged 17-54 years living in Yutian County. Demographic indicators, disease history, sexual behavior history, and other parameters were recorded at the interview using a questionnaire. A fluorescence detection method was used to quantify anti-HPV6, -11, -16, and -18 antibodies in venous blood serum. The rate of positive detection of any anti-HPV antibody (anti-HPV6, -11, -16, and -18) in the study population was 13.4%, and the individual positivity rates were 9.5%, 2.6%, 4.3%, and 0.7%, respectively. Peak rates of positivity for the anti-HPV16 antibody were found in women who were 36-40 and 46-50 years old. Seroprevalence of HPV16, which is high-risk for cervical cancer, was associated with the numbers of sexual partners. The rate of infection with high-risk HPV was low among Uygur women from rural areas, although there is a high incidence of cervical cancer in this group. Loyalty to one sexual partner decreased the risk of high-risk HPV infection. This study may provide useful reference data for the prevention and treatment of HPV and cervical cancer and for the application of HPV vaccines.

Humoral Immune Response Against Human Papillomavirus as Source of Biomarkers for the Prediction and Detection of Cervical Cancer

Cervical cancer (CC) is one of the main causes of death among women of reproductive age. Although there are different tests, the disease tends to be diagnosed at late stages. In recent years, the use of complementary tests or sequential diagnostic tests has been implemented. Nevertheless, the results are variable and not conclusive; therefore, more studies for improving the usefulness of these tests in diagnostics are necessary. The human papillomavirus (HPV) infection has been associated with both benign and malignant proliferation of skin and mucosal tissues. Furthermore, some HPV types have been classified as high risk due to their potential to cause cancer, and HPV16 is most frequently associated with this disease. Although between 70% and 80% of precancerous lesions are eliminated by the host's immune system, there is no available test to distinguish between regressive lesions from those that could progress to CC. An HPV infection generates a humoral immune response against L1 and L2 capsid proteins, which can be protective and a response against early proteins. The latter is not a protective response, but these antibodies can be used as markers to determine the stage of the infection and/or the stage of the cervical lesion. Up to now, the humoral immune response resulting from the HPV infection has been used to study the biology of the virus and the efficacy of the HPV vaccines. Although there are no conclusive results regarding the use of these antibodies for diagnosis, we hereby review the actual panorama of the antibody response against the HPV proteins during the development of the disease as well as their possible use as biomarkers for the progression of cervical lesions and of CC.

Detection of Human Papillomavirus 16-Specific IgG and IgM Antibodies in Patient Sera: A Potential Indicator of Oral Squamous Cell Carcinoma Risk Factor

The association between human papillomavirus type 16 (HPV16) and oral cancer has been widely reported. However, detecting anti-HPV antibodies in patient sera to determine risk for oral squamous cell carcinoma (OSCC) has not been well studied. In the present investigation, a total of 206 OSCC serum samples from the Malaysian Oral Cancer Database & Tissue Bank System, with 134 control serum samples, were analyzed by enzyme-linked immunosorbant assay (ELISA) to detect HPV16-specific IgG and IgM antibodies. In addition, nested PCR analysis using comprehensive consensus primers (PGMY09/11 and GP5(+)/6(+)) was used to confirm the presence of HPV. Furthermore, we have evaluated the association of various additional causal factors (e.g., smoking, alcohol consumption, and betel quid chewing) in HPV-infected OSCC patients. Statistical analysis of the Malaysian population indicated that OSCC was more prevalent in female Indian patients that practices betel quid chewing. ELISA revealed that HPV16 IgG, which demonstrates past exposure, could be detected in 197 (95.6%) OSCC patients and HPV16-specific IgM was found in a total of 42 (20.4%) OSCC patients, indicating current exposure. Taken together, our study suggest that HPV infection may play a significant role in OSCC (OR: 13.6; 95% CI: 3.89-47.51) and HPV16-specific IgG and IgM antibodies could represent a significant indicator of risk factors in OSCC patients.

HPV Type 6 and 18 Coinfection in a Case of Adult-Onset Laryngeal Papillomatosis: Immunization with Gardasil

Laryngeal papillomatosis (LP) is a rare human papillomavirus (HPV) related disease that often requires multiple surgical interventions and residual impairment of voice is almost inevitable. We report the case of a patient with adult onset recurrent LP, showing moderate dysplasia and coinfection with HPV types 6 and 18. The tetravalent HPV vaccine Gardasil was prescribed off label, with the aim of triggering an immunogenic response and consequently reducing the probability of further recurrences. The patient was followed for 9 months with no sign of relapse of his LP. The postexposure use of the anti-HPV vaccine could represent a promising therapeutic agent in established LP. Unfortunately, the potential efficacy of this new therapeutic option in this situation has been suggested only by isolated case reports. Further controlled studies, with a longer follow-up and a larger sample size, are needed to assess efficacy of Gardasil in LP.

Prevalence and factors associated with VIA positive result among clients screened at Family Guidance Association of Ethiopia, south west area office, Jimma model clinic, Jimma, Ethiopia 2013: a cross-sectional study

Background

Cervical cancer is the 2nd most frequent and top killer cancer among women in Ethiopia. Prevalence and factors associated with visual inspection with acetic acid (VIA) positive result is not studied yet at the study area.

Methods

A cross-sectional study was conducted at Jimma model clinic of Family Guidance Association of Ethiopia, from September 11, 2013 to October 11, 2013. Pertinent data of 334 screened clients were transferred to Epidata version3.1 using checklist, double data entry verification done and exported to SPSS version16.0. After cleaning the data, descriptive analysis was done and logistic regression model employed to identify predictors of VIA positive result. Statistical significance was declared at P < 0.05.

Results

Out of 334 screened clients, 43 (12.9 %) had VIA positive result. Initiation of sexual intercourse earlier than 16 years was found to be an independent predictor increasing the risk of VIA positive by 2.2 times as compared to clients who started at the age of 16 or more years (AOR [95 % CI] = 2.2 [1.1, 4.3]).

Conclusions

Early initiation of sexual intercourse was an independent predictor of VIA positive result in this study. Thus, any cervical cancer prevention and control effort at the study area should address the problem of early initiation of sexual intercourse.

Electronic supplementary material

The online version of this article (doi:10.1186/s13104-015-1594-x) contains supplementary material, which is available to authorized users.

HIV is an important risk factor for human papillomavirus types 16 and 18 seropositivity among sexually active men who have sex with men

OBJECTIVE

The aim of this study was to investigate whether HIV infection is a main risk factor for human papillomavirus (HPV)-16 and HPV-18 seropositivity in men who have sex with men (MSM), and what other risk factors are associated with HPV-16 and HPV-18 seropositivity in this population.

METHODS

Men who have sex with men visiting a sexually transmitted infection (STI) clinic in Amsterdam in 2008 to 2009 answered questions concerning demographics and sexual behavior. Sera were tested for HPV antibodies to the major HPV capsid protein L1 by Luminex-based multiplex serology. As it is known that site of exposure is associated with seropositivity, this analysis was restricted to MSM who reported receptive anal sex during the preceding 6 months. Using multivariable logistic regression, we examined whether HIV was associated with HPV serostatus.

RESULTS

Included in the study were 415 HIV-negative and 205 HIV-positive MSM reporting receptive anal sex. Median age of the study population was 39 years (interquartile range, 31-44). Human papillomavirus seroprevalence differed significantly between HIV-negative and HIV-positive MSM: 31% versus 65% (P < 0.001) for HPV-16 and 28% versus 51% (P < 0.001) for HPV-18. After adjusting for important risk factors HPV-16 (adjusted odds ratio, 2.80; 95% confidence interval, 1.75-4.49) and HPV-18 (adjusted odds ratio, 1.78; 95% confidence interval, 1.11-2.85), seropositivity was significantly more common in HIV-positive than in HIV-negative MSM. We could not identify other consistent risk factors for HPV-16 and HPV-18 seropositivity.

CONCLUSIONS

HIV infection is an important risk factor for HPV-16 and HPV-18 seropositivity among MSM reporting receptive anal sex in the preceding 6 months.

Detection of immunoglobulin IgA and IgG against human papilloma virus

The interest in human papilloma virus (HPV) seropositivity has increased considerably since HPV vaccines have become available worldwide. The aim of this study was to assess the performance of enzyme-linked immunosorbent assay (ELISA) in analyzing serum samples provided from women with and without genital DNA-HPV infection confirmed by polymerase chain reaction (PCR), for detection of specific antibodies of the isotypes IgG and IgA recognizing HPV-16 and -18, as well as virus-like particles (VLPs). From August to December 2013, 50 sexually active female patients between 18 and 35 years of age from the outpatient clinic at the university hospital were enrolled. In order to test them, positive controls were obtained from patients with HPV-induced lesions and who were DNA-HPV positive confirmed by PCR. A specific assay was used to identify antibodies to HPV VLPs by ELISA. The samples were divided into HPV positive and negative, and an ELISA detecting IgA and IgG anti-HPV-VLP was carried out. The effectiveness of ELISA and the kappa (k) index was obtained from the values entered in the receiver operating characteristic (ROC) curves for IgG and IgA. IgG-VLP-HPV-16 showed a good correlation between ELISA and PCR (k=0.75), and IgG-VLP-HPV-18 showed a very good correlation between ELISA and PCR (k=0.84). While the IgA antibody correlation was also positive, although weaker, IgA-VLP-HPV-16 was moderate (k=0.45) and IgA-VLP-HPV-18 good (k=0.66). The efficacy of the assay concerning IgG was: sensitivity, specificity, and accuracy were 82.3%, 92%, and 88% to IgG-VLP-HPV-16, and 100%, 92%, and 94% to IgG-VLP-HPV-18. The assay concerning IgA was: sensitivity, specificity, and accuracy were 64.7%, 80%, and 73.8% to IgA-VLP-HPV-16, and 100%, 80%, and 84.8% to IgA-VLP-HPV-18. IgG and IgA antibodies against HPV-16 and -18 can be detected in unvaccinated individuals by using the VLP that serve as the basis for bivalent HPV vaccine. The values for ELISA assays and the values found for IgG correlate good/very good with HPV-16/18 detected by PCR.

HPV seroconversion following anal and penile HPV infection in HIV-negative and HIV-infected MSM

BACKGROUND

We assessed human papillomavirus (HPV) seroconversion following anal and penile HPV infection in HIV-negative and HIV-infected men who have sex with men (MSM).

METHODS

MSM aged ≥18 years were recruited in Amsterdam, the Netherlands (2010-2011), and followed up semiannually. Antibodies against 7 high-risk HPV types in baseline and 12-month serum samples were tested using a multiplex immunoassay. Baseline, 6-, and 12-month anal and penile samples were tested for HPV DNA using the SPF10-PCR DEIA/LiPA25 system. Statistical analyses were performed using logistic regression with generalized estimating equations.

RESULTS

Of 644 MSM included in the analysis, 245 (38%) were HIV-infected. Median age was 38 years for HIV-negative and 47 years for HIV-infected MSM (P < 0.001). Seroconversion against ≥1 of the 7 HPV types was observed in 74 of 396 (19%) HIV-negative and 52 of 223 (23%) HIV-infected MSM at risk (P = 0.2). Incident [adjusted OR (aOR) 2.0; 95% confidence interval (CI), 1.1-3.4] and persistent (aOR 3.7; 95% CI, 1.5-9.5) anal HPV infections were independently associated with type-specific seroconversion in HIV-negative MSM. In HIV-infected MSM, there was a nonsignificant positive association between penile HPV infection at any time point and seroconversion (aOR 1.7; 95% CI, 0.9-3.2).

CONCLUSIONS

Incident or persistent anal HPV infection was an independent determinant of seroconversion in HIV-negative MSM.

IMPACT

Our data support that seroresponse may vary per anatomic site and that persistent HPV infections are more likely to elicit a detectable humoral immune response.

Associations between human papillomavirus and history of cancer among U.S. adults in the National Health and Nutrition Examination Survey (2003-2010)

Background:

Human papillomavirus (HPV) is an infectious agent that has been associated with human cancer. We have updated the U.S. population sero-prevalence using a large National Health and Nutrition Examination Survey (NHANES) sample of adults from 2003 to 2010, and have analysed the associations between HPV seropositivity and self-reported history of cancer.

Methods:

Four cross-sectional cycles (2003–2004, 2005–2006, 2007–2008, and 2009–2010) were used, for a total of 12 759 participants who had both cancer history and HPV serum information.

Results:

The sero-prevalences of HPV types 6, 11, 16, and 18 were 15.0%, 4.8%, 11.5%, and 4.1%, respectively. Females had significantly higher HPV prevalence than males (P<0.05) for all subtypes. Positive associations between HPV 16/18 seropositivity and lifetime history of any cancer (adjusted odds ratio-OR_adj=1.68; 95% CI: 1.35, 2.01), history of any of eight selected cancers (OR_adj=2.63; 95% CI: 1.78, 3.90), lung cancer (OR_adj=5.14; 95% CI: 1.29, 20.44), and cervical cancer (OR_adj=2.55; 95% CI: 1.63, 3.98) were observed.

Conclusions:

The finding of significant associations between HPV 16/18 seropositivity and lifetime history of cancer adds epidemiological evidence to the carcinogenicity potential of HPV 16 and 18 in other tissues. With increasing coverage of the HPV vaccine in the U.S., future NHANES data and sample collection may allow further detailed evaluation of the population impact of the HPV vaccination on cancer prevention.

Serological prevalence and persistence of high-risk human papillomavirus infection among women in Santiago, Chile

Background

Human papillomavirus (HPV) serology is a main factor for designing vaccination programs and surveillance strategies; nevertheless, there are few reports of HPV seroprevalence in the general population, especially in Latin America. This study aimed to describe high-risk HPV serological prevalence, persistence, and association with concurrent cervical infection, in Chilean women.

Methods

1021 women from the general population, aged 15–85 years, were studied in 2001 of whom 600 were reexamined in 2006. The assessments at both time points included cervical HPV DNA testing, HPV antibody testing, cervical cytology and a sociodemographic/behavioral questionnaire. HPV DNA and antibodies against L1 protein of types 16, 18, 31, 33, 35, 45, 52, and 58 were assessed by reverse line blot and multiplex serology, respectively.

Results

Seropositivity was high at both baseline (43.2%) and follow-up (50.2%) and increased with age (p < 0.001); corresponding DNA prevalences were 6.7% and 8.7%. DNA and seroprevalence were associated at baseline (p = 0.01 for any HPV). Early age at first sexual intercourse and having had two or more sexual partners were independently associated with seropositivity. Most (82.0%) initially seropositive women remained seropositive at follow-up; 21.6% of initially seronegative women seroconverted, reaching 17.5% among women older than 60 years of age. ASCUS or worse cytology was correlated with HPV DNA positivity but not with HPV seropositivity.

Conclusion

HPV seroprevalence studies are a useful tool for learning about the dynamics of HPV infection in a community. This study contributes to understanding the natural history of HPV infection and provides a baseline assessment before the incorporation of HPV vaccination into a national program.

Seroepidemiology of high-risk HPV in HIV-negative and HIV-infected MSM: the H2M study

BACKGROUND

Men who have sex with men (MSM), in particular HIV-infected MSM, are at increased risk for diseases related to human papilloma virus (HPV). Our goal was to assess the effect of HIV status on the presence of type-specific antibodies against seven high-risk HPV types in HPV-unvaccinated MSM. Moreover, we compared determinants of HPV seropositivity between HIV-negative and HIV-infected MSM.

METHODS

MSM ≥18 years of age were recruited from the Amsterdam Cohort Studies, a sexually transmitted infection clinic, and an HIV-treatment center in Amsterdam, the Netherlands. Participants completed a risk-factor questionnaire; serum samples were analyzed using a fluorescent bead-based multiplex assay.

RESULTS

MSM (n = 795) were recruited in 2010 to 2011; 758 MSM were included in this analysis. Median age was 40.1 years (interquartile range 34.8-47.5) and 308 MSM (40.6%) were HIV-infected. Seroprevalence of HPV-16 was 37.1% in HIV-negative and 62.7% in HIV-infected MSM (P < 0.001); seroprevalence of HPV-18 was 29.1% in HIV-negative MSM and 42.5% in HIV-infected MSM (P < 0.001). Similar patterns of seroprevalence were observed for HPV types 31, 33, 45, 52, and 58. In multivariable analyses, HPV seropositivity was associated with HIV infection [adjusted OR = 2.1; 95% confidence interval, 1.6-2.6]. In multivariable analyses stratified by HIV status, increasing age and number of lifetime male sex partners were significantly associated with HPV seropositivity in HIV-negative, but not HIV-infected MSM.

CONCLUSIONS

Seroprevalence of high-risk HPV types is high among unvaccinated MSM.

IMPACT

HIV infection is a strong and independent determinant for HPV seropositivity, which we hypothesize is because of increased persistence of HPV infection in HIV-infected MSM.

Anal, penile, and oral high-risk HPV infections and HPV seropositivity in HIV-positive and HIV-negative men who have sex with men

The effects of single or multiple concordant HPV infections at various anatomical sites on type-specific HPV seropositivity are currently unknown. In this cross-sectional study we assessed whether high-risk HPV infections at various anatomical sites (i.e., anal canal, penile shaft, and oral cavity), as well as concordant infections at multiple anatomical sites, were associated with type-specific seropositivity in HIV-positive and HIV-negative MSM. MSM aged ≥ 18 years were recruited in Amsterdam, the Netherlands (2010-2011). Baseline anal, penile, and oral samples were analyzed for HPV DNA and genotyped using a highly sensitive PCR and reverse line blot assay. Virus-like particle (VLP) based multiplex immunoassay was used to asses HPV-specific serum antibodies against L1 VLPs. The associations between HPV infections and type-specific seropositivity of seven high-risk HPV types (7-hrHPV: types 16, 18, 31, 33, 45, 52, 58) were estimated using logistic regression analyses with generalized estimating equations. We found that 86% of 306 HIV-positive MSM and 62% of 441 HIV-negative MSM were seropositive for at least one 7-hrHPV type. 69% of HIV-positive and 41% of HIV-negative MSM were infected with at least one 7-hrHPV type at the anus, penis, or oral cavity. In multivariable analyses, 7-hrHPV seropositivity was associated with type-specific anal (and not penile) 7-hrHPV infection, and did not significantly increase with a higher number of infected anatomical sites. Oral 7-hrHPV infection showed a positive, albeit non-significant, association with seropositivity. In conclusion, seropositivity among MSM appears to be largely associated with anal HPV infection, irrespective of additionally infected anatomical sites.

Increased alpha-9 human papillomavirus species viral load in human immunodeficiency virus positive women

BACKGROUND

Persistent high-risk (HR) human papillomavirus (HPV) infection and increased HR-HPV viral load are associated with the development of cancer. This study investigated the effect of human immunodeficiency virus (HIV) co-infection, HIV viral load and CD4 count on the HR-HPV viral load; and also investigated the predictors of cervical abnormalities.

METHODS

Participants were 292 HIV-negative and 258 HIV-positive women. HR-HPV viral loads in cervical cells were determined by the real-time polymerase chain reaction.

RESULTS

HIV-positive women had a significantly higher viral load for combined alpha-9 HPV species compared to HIV-negative women (median 3.9 copies per cell compared to 0.63 copies per cell, P = 0.022). This was not observed for individual HPV types. HIV-positive women with CD4 counts >350/μl had significantly lower viral loads for alpha-7 HPV species (median 0.12 copies per cell) than HIV-positive women with CD4 ≤350/μl (median 1.52 copies per cell, P = 0.008), but low CD4 count was not significantly associated with increased viral load for other HPV species. High viral loads for alpha-6, alpha-7 and alpha-9 HPV species were significant predictors of abnormal cytology in women.

CONCLUSION

HIV co-infection significantly increased the combined alpha-9 HPV viral load in women but not viral loads for individual HPV types. High HR-HPV viral load was associated with cervical abnormal cytology.

Association of HPV types 6, 11, 16, and 18 DNA detection and serological response in unvaccinated adolescent women

Antibodies directed against the human papillomavirus (HPV) L1 protein are detected in approximately 70% of individuals with HPV infections. The factors associated with a serological response are not characterized. It is hypothesized that the HPV viral load, duration of detection, or both would be associated with seropositivity in adolescent women. Adolescent women (n = 117), ages 15-17 at enrolment were followed for a mean of 6.2 years. Quarterly vaginal swabs (mean 22 per participant) were used to identify HPV 6, 11, 16, or 18 DNA (Roche PCR/Linear Array). Type-specific HPV infection was defined as ≥2 positive assays. To approximate viral load, Roche PCR/Linear Array test strips were scored visually based on the strength of signal relative to beta-globin controls. Sera collected near the end of study were tested by cLIA. Regression models were fit to assess associations between strength of signal (as represented by mean and cumulative strength of signal), duration of HPV detection, seropositivity, and serotiter. Detection of HPV DNA was associated with seropositivity for four types combined and for types 6, 16, and 18. Overall, 70.1% of DNA positive episodes were associated with type-specific seropositivity. The cumulative HPV DNA signal strength during periods of HPV detection for types 6, 11, 16, and 18 combined was associated with seropositivity (OR = 1.21, 95% CI 1.02-1.44 P = 0.026). No other HPV DNA predictors were found to be associated with seropositivity or serotiter.

Characteristics of HPV-specific antibody responses induced by infection and vaccination: cross-reactivity, neutralizing activity, avidity and IgG subclasses

OBJECTIVES

In order to assess HPV-specific IgG characteristics, we evaluated multiple aspects of the humoral antibody response that will provide insight in the HPV humoral immune response induced by HPV infection and vaccination.

METHODS

Cross-reactivity of HPV-specific antibodies induced by infection or vaccination was assessed with VLP16 or 18 inhibition using a VLP-based multiplex immunoassay (MIA) for HPV16, 18, 31, 33, 45, 52 and 58. HPV16/18 specific IgG1-4 subclasses and avidity were determined with the VLP-MIA in sera after HPV infection and after vaccination. Neutralizing antibodies were determined in a small subset of single-seropositive and multi-seropositive naturally derived antibodies.

RESULTS

Naturally derived antibodies from single-positive sera were highly genotype-specific as homologue VLP-inhibition percentages varied between 78-94%. In multi-positive sera, cross-reactive antibodies were observed both within and between α7 and α9 species. After vaccination, cross-reactive antibodies were mainly species-specific. Avidity of vaccine-derived HPV-specific antibodies was 3 times higher than that of antibodies induced by HPV infection (p<0.0001). IgG1 and IgG3 were found to be the predominant subclasses observed after HPV infection and vaccination. In the small subset tested, the number of single-positive sera with neutralizing capacity was higher than of multi-positive sera.

CONCLUSION

Naturally derived HPV-specific antibodies from single-positive samples showed different characteristics in terms of cross-reactivity and neutralizing capacity compared with antibodies from multi-positive sera. Post-vaccination, HPV antibody avidity was approximately 3 times higher than antibody avidity induced by HPV infection. Therefore, antibody avidity might be a potential surrogate of protection.

Pre-vaccination seroprevalence of 15 human papillomavirus (HPV) types among women in the population-based Slovenian cervical screening program

OBJECTIVES

To estimate seroprevalence of 11 high-risk (hr) HPV types and four low-risk (lr) HPV types among 20-64 years old Slovenian women participating in the population-based cervical cancer screening program.

METHODS

Serum samples from 3259 women were tested for HPV type-specific antibodies with a multiplexed pseudovirion-based serological assay (PsV-Luminex).

RESULTS

Seropositivity for any of the 15 HPV types was 65.7%, any of the 11 hr-HPV types 59.2%, and any of the four lr-HPV types 33.1%. Antibodies against at least one of the four vaccine HPV types (HPV 6, 11, 16, 18) were detected in 40.8% women. Among hr-HPV types, seropositivity was highest for HPV 16 (25.2%) and among lr-HPV types for HPV 6 (19.1%). Age-specific HPV16 seropositivity was highest among 30-39 years old (29.6%) and decreased with increasing age to 14.0% among 60-64 years old.

CONCLUSION

The lifetime sexual exposure to genital HPV types is substantial, emphasising the need for HPV vaccination.

Human papillomavirus vaccines--immune responses

Prophylactic human papillomavirus (HPV) virus-like particle (VLP) vaccines are highly effective. The available evidence suggests that neutralising antibody is the mechanism of protection. However, despite the robust humoral response elicited by VLP vaccines, there is no immune correlate, no minimum level of antibody, or any other immune parameter, that predicts protection against infection or disease. The durability of the antibody response and the importance of antibody isotype, affinity and avidity for vaccine effectiveness are discussed. Once infection and disease are established, then cellular immune responses are essential to kill infected cells. These are complex processes and understanding the local mucosal immune response is a prerequisite for the rational design of therapeutic HPV vaccines. This article forms part of a special supplement entitled "Comprehensive Control of HPV Infections and Related Diseases" Vaccine Volume 30, Supplement 5, 2012.

Patterns of human papillomavirus DNA and antibody positivity in young males and females, suggesting a site-specific natural course of infection

Background

To monitor the impact of human papillomavirus types 16 and 18 vaccine on HPV infection dynamics in the Netherlands, we started an ongoing study in sexually transmitted infection (STI) clinics in 2009. Here, we analyze baseline type-specific HPV DNA and HPV-specific antibody positivity rates.

Methods

We enrolled 3569 men and women, 16–24 years of age, from 14 STI clinics, and estimated genital and anal HPV DNA and antibody positivity rates of 7 main carcinogenic HPV types. Generalized estimating equations regression analyses were applied to determine risk factors for, and associations between, type-specific HPV DNA and antibody positivity.

Results

Genital HPV DNA positivity rates were higher in women than in men; anal HPV DNA was especially high in men who have sex with men (MSM). HPV antibody seropositivity rates were also highest in women and MSM. High-risk sexual behavior was predictive of both HPV DNA and antibody positivity. Despite a strong correlation in serological profiles for multiple HPV types, seropositivity was independently associated with homologous HPV DNA detection.

Conclusions

HPV DNA and antibody positivity rates are higher in women and MSM than in heterosexual men, but their association is similar across gender. This suggests a site-specific natural course of infection.

Serum antibodies to human papillomavirus (HPV) pseudovirions correlate with natural infection for 13 genital HPV types

BACKGROUND

Serology for human papillomaviruses (HPV) types -16 and -18 is established as an important tool for studies of HPV vaccinology and epidemiology. However, as there are a large number of oncogenic genital types of HPV there is a need for development of high-throughput, validated HPV serological assays that can be used for more comprehensive seroepidemiological studies and for research on multivalent HPV vaccines.

OBJECTIVES

To develop a multiplexed pseudovirion-based serological assay (PsV-Luminex) encompassing 21 HPV types and validate the method by correlating the serology with the presence of type specific HPV DNA in cervical samples.

STUDY DESIGN

Cervical swabs from 3,291 unvaccinated women attending organized cervical screening in Slovenia were tested with 3 different HPV DNA detection methods and presence of HPV DNA compared to presence of serum antibodies to pseudovirions from 15 genital HPV types (HPV-6,-11,-16,-18,-31,-33,-35,-39,-45,-52,-56,-58,-59,-68,-73).

RESULTS

On average 51% of the HPV DNA positive women were seropositive for the same HPV type that was detected in the cervical specimen. We found a strong correlation with presence of HPV DNA and antibodies to the same HPV type for 13/15 genital HPV types (median OR = 5.7, CI 95% = 2.4-12.9). HPV-52 serology failed the validation and HPV-11 serology could not be validated because only a single woman was positive for HPV-11 DNA. The correlation between serology and HPV DNA status tended to be stronger among women infected with single HPV type (median OR=10.5, CI 95% = 2.4-48.4) than among women with multiple HPV infections (median OR = 4.6, CI 95% = 1.8-11.7).

CONCLUSIONS

A multiplexed HPV PsV-Luminex assay has been developed and validated to correlate with natural HPV infection for 13 HPV types, thus enabling more comprehensive studies in HPV epidemiology and vaccine research.

Risk factors for VIA positivity and determinants of screening attendances in Dar es Salaam, Tanzania

Background

Tanzania is among the countries in the world where the cervical cancer incidence is estimated to be highest. Acknowledging an increase in the burden of cervical cancer, VIA was implemented as a regional cervical cancer screening strategy in Tanzania in 2002. With the aim of describing risk factors for VIA positivity and determinants of screening attendances in Tanzania, this paper present the results from a comparative analysis performed among women who are reached and not reached by the screening program”.

Methods

14 107 women aged 25–59 enrolled in a cervical cancer screening program in Dar es Salaam in the period 2002 – 2008. The women underwent VIA examination and took part in a structured questionnaire interview. Socioeconomic characteristics, sexual behavior, HIV status and high-risk (HR) HPV infection were determined in a subpopulation of 890 who participated and 845 who did not participate in the screening.

Results

Being widowed/separated OR=1.41 (95% CI: 1.17-1.66), of high parity OR=3.19 (95% CI: 1.84-5.48) of low education OR= 4.30 (95% CI: 3.50-5.31) and married at a young age OR=2.17 (95% CI: 1.37-3.07) were associated with being VIA positive. Women who participated in the screening were more likely to be HIV positive OR= 1.59 (95% CI. 1.14-2.25) in comparison with women who had never attended screening, while no difference was found in the prevalence of HR-HPV infection among women who had attended screening and women who had not attended screening.

Conclusion

Women who are widowed/separated, of high parity, of low education and married at a young age are more likely to be VIA positive and thus at risk of developing cervical cancer. The study further documents that a referral linkage between the HIV care and treatment program and the cervical cancer screening program is in place in the setting studied, where HIV positive were more likely to participate in the cervical cancer screening program than HIV negative women.

Treatment failure in patients with HPV 16-induced vulvar intraepithelial neoplasia: understanding different clinical responses to immunotherapy

Failure of the immune system to launch a strong and effective immune response to high-risk HPV is related to viral persistence and the development of anogenital (pre)malignant lesions such as vulvar intraepithelial neoplasia (VIN). Different forms of immunotherapy, aimed at overcoming the inertia of the immune system, have been developed and met with clinical success. Unfortunately these, in principal successful, therapeutic approaches also fail to induce clinical responses in a substantial number of cases. In this review, the authors summarize the traits of the immune response to HPV in healthy individuals and in patients with HPV-induced neoplasia. The potential mechanisms involved in the escape of HPV-induced lesions from the immune system indicate gaps in our knowledge. Finally, the interaction between the immune system and VIN is discussed with a special focus on the different forms of immunotherapy applied to treat VIN and the potential causes of therapy failure. The authors conclude that there are a number of pre-existing conditions that determine the patients' responsiveness to immunotherapy. An immunotherapeutic strategy in which different aspects of immune failure are attacked by complementary approaches, will improve the clinical response rate.