The effect of a booster dose of HPV tetravalent vaccine after 51 months: implications for extended vaccination schedules / El efecto de un refuerzo de la vacuna tetravalente de VPH después de 51 meses: implicaciones para un esquema de vacunación extendido

Abstract: Objective: To asses the non-inferiority between two different vaccination schedules one month after the administration of the third dose. Materials and methods: We evaluated the anti-HPV 16/18 antibody titers induced by quadrivalent HPV vaccine administered using two different schedules in girls 9 to 10-year-old girls: a traditional (0-2-6) and an alternative (0-6-50). Blood samples were collected at month 7, 21 and 51. Results: The antibody geometric mean titer ratios one month after the application of the third dose -month 51 for the alternative and month 7 for the traditional- were 1.55 for HPV16 (95%CI, 1.15-2.08) and 1.53 for HPV18 (95%CI, 1.12-2.09). The seropositive rate was above 99% in both groups. Conclusions: The application of an alternative 3-dose schedule in 9 to 10-year-old girls induces a non-inferior immune response compared to the standard one month after the last dose. Further research is needed to understand the minimal number of doses and their timing to provide the best coverage for HPV infection.

Resumen: Objetivo: Evaluar la no inferioridad entre dos diferentes esquemas de vacunación un mes después de la administración de la tercera dosis. Material y métodos: Se evaluaron los títulos de anticuerpos anti-VPH 16/18 inducidos por la vacuna contra VPH tetravalente administrada en niñas de 9 a 10 años utilizando dos esquemas diferentes: tradicional (0-2-6) y alternativo (0-6-50). Se recolectaron muestras en los meses 7, 21 y 51. Resultados: La media geométrica de títulos de anticuerpos un mes después de la aplicación de la tercera dosis -mes 51 para la alternativa y mes 7 para el tradicional- fueron 1.55 para HPV16 (95% IC 1.15-2.08) y 1.53 para HPV18 (95% IC 1.12-2.09). La tasa de seropositividad fue superior a 99% en ambos grupos. Conclusiones: la aplicación de un esquema alternativo de tres dosis (0-6-50 meses) en niñas parece inducir una respuesta inmune no inferior al esquema tradicional un mes después de la última dosis. Se necesitan más estudios para determinar las dosis mínimas e intervalos óptimos para obtener la mejor cobertura para la infección por VPH.

Detection of High-Risk Human Papillomavirus in Cervix Sample in an 11. 3-year Follow-Up after Vaccination against HPV 16/18 / Detecção de papilomavírus humano de alto risco em amostras de colo uterino em 11. 3 anos de acompanhamento após vacinação contra HPV 16/18

Abstract Purpose the aim of this study was to evaluate the pattern of human papillomavirus (HPV) detection in an 11.3-year post-vaccination period in a cohort of adolescent and young women vaccinated or not against HPV 16/18. Methods a subset of 91 women from a single center participating in a randomized clinical trial (2001-2010, NCT00689741/00120848/00518336) with HPV 16/18 AS04- adjuvanted vaccine was evaluated. All women received three doses of the HPV vaccine (n = 48) or a placebo (n = 43), and cervical samples were collected at 6-month intervals. Only in this center, one additional evaluation was performed in 2012. Up to 1,492 cervical samples were tested for HPV-DNA and genotyped with polymerase chain reaction (PCR). The vaccine group characteristics were compared by Chi-square or Fisher exact or Mann-Whitney test. The high-risk (HR)-HPV 6-month-persistent infection rate was calculated. The cumulative infection by HPV group was evaluated by the Kaplan-Meier method and the log-rank test. Results the cumulative infection with any type of HPV in an 11.3-year period was 67% in the HPV vaccine group and 72% in the placebo group (p = 0.408). The longitudinal analysis showed an increase of 4% per year at risk for detection of HR-HPV (non-HPV 16/ 18) over time (p = 0.015), unrelated to vaccination. The cumulative infection with HPV 16/18 was 4% for the HPV vaccine group and 29% for the placebo group (p = 0.003). There were 43 episodes of HR-HPV 6-month persistent infection, unrelated to vaccination. Conclusions this study showed themaintenance of viral detection rate accumulating HR-HPV (non-HPV-16-18) positive tests during a long period post-vaccination, regardless of prior vaccination. This signalizes that the high number of HPV-positive testsmay be maintained after vaccination.

Resumo Objetivos avaliar o padrão de detecção do papilomavírus humano (HPV) em um período de 11.3 anos após a vacinação em uma coorte de adolescentes e mulheres jovens vacinadas ou não contra HPV 16/18. Métodos avaliou-se um subgrupo de 91 mulheres de um único centro, participantes de ensaio clínico randomizado (2001-2010, NCT00689741/00120848/00518336) com a vacina contra HPV 16/18 com adjuvante AS04. Todas as mulheres receberam três doses de vacina contra HPV (n = 48) ou placebo (n = 43), e tiveram amostras cervicais coletadas em intervalos de 6 meses. Somente neste centro, uma avaliação adicional foi realizada em 2012. Um total de 1.492 amostras cervicais foram testadas para DNA-HPV e genotipadas com reação em cadeia da polimerase (RCP). As características dos grupos de vacina contra HPV ou placebo foram comparadas pelo teste de Qui-quadrado ou teste exato de Fisher ou teste de Mann-Whitney. A infecção persistente por 6meses pelo HPV de alto risco (AR) foi calculada. A infecção cumulativa por grupo foi avaliada pelo método de Kaplan-Meier e pelo teste log-rank. Resultados a infecção cumulativa com qualquer tipo de HPV em11.3 anos foi de 67% no grupo vacina contra HPV e de 72% no grupo placebo (p = 0,408). A análise longitudinal mostrou um aumento de 4% ao ano no risco de detecção de HR-HPV (não-HPV 16/18) ao longo do tempo (p = 0,015), não relacionado com a vacinação. A infecção cumulativa com HPV 16/18 foi de 4% para o grupo vacina contra HPV e 29% para o grupo placebo (p = 0,003). Houve 43 episódios de infecção persistente por 6 meses por HR-HPV, não relacionados com a vacinação. Conclusões este estudo mostrou a manutenção da taxa de detecção viral, acumulando testes positivos de HR-HPV (não HPV-16-18) durante longo período pósvacinação, independentemente da vacinação prévia. Isto sinaliza que a alta positividade dos testes de HPV pode ser mantida após a vacinação.

Identificaiton of Novel Immunogenic Human Papillomavirus Type 16 E7-Specific Epitopes Restricted to HLA-A*33;03 for Cervical Cancer Immunotherapy

PURPOSE: To identify new immunogenic HLA-A*33;03-restricted epitopes from the human papillomavirus (HPV) 16 E7 protein for immunotherapy against cervical cancer. MATERIALS AND METHODS: We synthesized fourteen overlapping 15-amino acid peptides and measured intracellular interferon-γ (IFN-γ) production in PBMC and CD8+ cytotoxic T lymphocytes (CTLs) after sensitization with these peptides using flow cytometry and ELISpot assay. The immunogenicity of epitopes was verified using a ⁵¹Cr release assay with SNU1299 cells. RESULTS: Among the fourteen 15-amino acid peptides, E7₄₉₋₆₃ (RAHYNIVTFCCKCDS) demonstrated the highest IFN-γ production from peripheral blood mononuclear cells (PBMCs), and CD8+ CTLs sensitized with E7₄₉₋₆₃ showed higher cytotoxic effect against SNU1299 cells than did CD8+ CTLs sensitized with other peptides or a negative control group. Thirteen 9- or 10-amino acid overlapping peptides spanning E7₄₉₋₆₃, E7₅₀₋₅₉ (AHYNIVTFCC), and E7₅₂₋₆₁ (YNIVTFCCKC) induced significantly higher IFN-γ production and cytotoxic effects against SNU1299 cells than the other peptides and negative controls, and the cytotoxicity of E7₅₀₋₅₉- and E7₅₂₋₆₁-sensitized PBMCs was induced via the cytolytic effect of CD8+ CTLs. CONCLUSION: We identified E7₅₀₋₅₉ and E7₅₂₋₆₁ as novel HPV 16 E7 epitopes for HLA-A*33;03. CD8+ CTL sensitized with these peptides result in an antitumor effect against cervical cancer cells. These epitopes could be useful for immune monitoring and immunotherapy for cervical cancer and HPV 16-related diseases including anal cancer and oropharyngeal cancer.

Normalización de un método inmunoquímico para detectar Papilomavirus humano tipo 16 en lesiones cérvico-uterinas / Standardization of immunochemical method for detection of type 16 human papilomavirus in cervix uterine lesions

Introducción: la infección por Papilomavirus Humano (PVH) es la condición necesaria para la aparición y desarrollo del cáncer cérvico-uterino. Los genotipos de alto riesgo oncogénico son los causantes de este tipo de neoplasia y dentro de ellos el más frecuente es el PVH 16, que se encuentra aproximadamente en el 60 % de los casos. Los métodos de diagnóstico comerciales resultan costosos para países con escasos recursos económicos, lo que sugiere la búsqueda de alternativas empleando protocolos sencillos y baratos. Objetivos: normalizar un método inmunoquímico para la detección del antígeno L1 de PVH tipo 16 en muestras cérvico-uterinas de pacientes con lesiones intraepiteliales escamosas y determinar la coincidencia entre el método normalizado y la Reacción en Cadena de la Polimerasa en Tiempo Real (RCP-TR), como técnica de referencia, para estimar la utilidad de dicho método en el diagnóstico de la infección por este genotipo viral. Métodos: se compararon tres procedimientos de inmunotinción (Indirecto de inmunoperoxidasa en dos pasos, Estreptavidina-Biotina y Amplificación por polímero) respecto a sensibilidad analítica, tinción inespecífica de fondo y tiempo de terminación, para la detección de la proteína L1 de PVH 16 en líneas celulares derivadas de carcinomas cervicales humanos y en muestras cérvico-uterinas utilizadas como controles. El protocolo normalizado se aplicó a muestras cérvico-uterinas de mujeres entre 30 y 59 años, 82 con lesiones intraepiteliales cervicales y 10 sin antecedentes de alteraciones citológicas, a las que además se les determinó PVH 16 mediante RCP-TR. Resultados: el procedimiento de Estreptavidina-Biotina resultó el más sensible y específico. La coincidencia entre el método inmunoquímico y la RCP-TR fue de un 98,6 por ciento, la sensibilidad fue de un 98,57 por ciento y la especificidad de un 91,67 por ciento, con valores predictivos negativo y positivo por encima del 90 por ciento. Conclusiones: se demostró la validez del método inmunoquímico como prueba confirmatoria de la infección por PVH 16. Dicho método probó ser sensible, sencillo y no requiere de una compleja infraestructura para detectar PVH 16 en muestras cervicales. Además, esta técnica permite obtener información rápidamente y evita el uso de métodos invasivos(AU)

Introduction: Human Papillomavirus (HPV) infection is the necessary condition for the occurernce and development of cervical cancer. The high oncogenic risk genotypes are the responsible for this type of neoplasia and the most frequent is HPV 16 that affects roughly 60 percent of cases. Commercial kits for HPV detection are expensive for resource-poor countries, which suggests the search for alternative throguh non-expensive simple protocoles. Objectives: to standardize an immunochemical method for the detection of HPV 16 L1 antigen in cervical samples of patients with squamous intraepithelial lesions and to determine the diagnostic coincidence between the immunochemical method and the real-time polymerase chain reaction to estimate the usefulness of this method for the detection of cervical infection with this viral genotype. Methods: three immunostaining methods (Two-Step Indirect Immunoperoxidase, Labelled Streptavidin-Biotin and Enhanced Polymer) were compared in terms of analytical sensitivity, nonspecific background staining and time of completion, for the detection of protein L1 of HPV-16 in a cell line derived from human cervical carcinoma and clinical samples from uterine cervix. The optimized protocol was applied to 82 cervical samples from women aged 30-59 years with squamous intraepithelial lesions and to 10 samples of sexually active women without previous signals of positive cytology. The presence of type 16 HPV was also detected with the aid of RT-PCR. Results: the Streptavidin-Biotin system was the most sensitive and specific. The diagnostic agreement between the immunochemical method and the real-time polymerase chain reaction reached 98.6 percent, sensitivity was 98.57 percent and specificity was 91.67 %, with positive and negative predictive values above 90 percent. Conclusions: the validity of the immunochemical method as a confirmatory test for infection by HPV-16 has been demonstrated. The normalized immunochemical method proved to be a sensitive, simple, relatively fast method to detect HPV from clinical samples of cervical cells. Furthermore, this method provides information quickly, avoiding the use of invasive methods in patients(AU)

Antibody detection against HPV16 E7 & GP96 fragments as biomarkers in cervical cancer patients.

Background & objectives: Cervical cancer is the second most frequent cancer among females worldwide, especially human papilloma viruses (HPV) types 16 and 18. In viral systems the identification of serological markers would facilitate the diagnosis of HPV infections and virus-related disease. The aim of the present investigation was to determine and search for serologic markers in cervical cancer patients associated with HPV. Methods: A total of 58 Iranian women with invasive cervical carcinoma including adenocarcinoma and squamous cell carcinoma (SCC) were included. Serum antibody response to HPV infections in patients was detected by Western blot and ELISA techniques based on recombinant HPV16E7 and the N-terminal and C-terminal fragments of gp96 (NT-gp96 and CT-gp96) proteins. These recombinant proteins were expressed in Escherichia coli as a His-tag protein and purified using affinity chromatography. Results: The ELISA results indicated that patients with high antibody response to HPV16E7 had significant seroreactivity to CT-gp96 fragment. In Western blot analysis, a strong association between anti-E7, anti-NT-gp96 and anti-CT-gp96 reactivity and cervical cancer was obtained using purified recombinant proteins. In adenocarcinoma cases, no significant difference was observed in seroreactivities between normal and patients. Interpretation & conclusions: The evaluation of cervical cancer patients' seroreactivities against three recombinant proteins (rE7, rNT-gp96 and rCT-gp96) showed significantly higher levels of these markers in SCC only, but not in adenocarcinoma and control groups. Also, the usage of both techniques (ELISA and Western blotting) can provide more reliable tools for diagnosis of cervical cancer.

Production of immunogenic human papillomavirus-16 major capsid protein derived virus like particles.

Background & objective: Recombinant DNA technology allows expression of the human papillomavirus (HPV) major capsid protein (L1) in heterologous expression systems and the recombinant protein self assembles to virus-like particles (VLP). We took up this study to produce recombinant HPV-16 L1 in yeast, establish the process of recombinant L1 derived VLP preparation and develop an ELISA using VLP as the antigen for serological evaluation of anti HPV-16 L1 antibody status. Methods: Complete HPV-16 L1 was amplified from genomic DNA of an esophageal cancer biopsy, cloned and the protein was expressed in a galactose-inducible Saccharomyces cerevisiae expression system. Self assembled VLP was purified by a two-step density gradient centrifugation process and the VLP preparation used to test its suitability in developing an ELISA. Results: The recombinant protein was predominantly a ~55 KD species with distinct immunoreactivity and formed VLP as confirmed by electron microscopy. An ELISA using the VLP showed its efficacy in appropriate immunoreactivity to serum/plasma IgG. Interpretation & conclusions: Recombinant HPV-16 capsid protein derived VLP was produced and the VLP antigen based ELISA can be used to probe serological association of HPV with different clinical conditions. The VLP technology can be improved further and harnessed for future vaccine development efforts in the country.