Objectif: Les deux objectifs principaux de cette thèse étaient de développer 1) des modèles mathématiques pour prédire l’efficacité populationnelle de la vaccination contre les VPH et 2) des méthodes pour quantifier l’incertitude autour des prédictions de ces modèles. Méthode: Nous avons développé trois modèles mathématiques: 1) un modèle statique compartimental de l’histoire naturelle du cancer du col de l’utérus (Modèle1), 2) un modèle dynamique individus-centré de l’infection aux VPH (Modèle2), et 3) un modèle dynamique individus-centré de l’histoire naturelle des maladies associées aux VPH (Modèle3). Résultats: Les trois modèles ont prédit que la vaccination des filles pourrait diminuer substantiellement le fardeau des maladies associées aux VPH, au Canada. La durée de protection vaccinale a été identifiée comme étant le paramètre influençant le plus les résultats d’efficacité populationnelle. Le modèle 3 a prédit que le vaccin bivalent pourrait prévenir légèrement plus de cas de cancer du col sur le long terme, alors que le vaccin quadrivalent a le potentiel de réduire drastiquement les condylomes sur le court terme. Finalement, le modèle 3 a suggéré que le vaccin nonavalent actuellement en développement pourrait rapporter des bénéfices additionnels importants si son efficacité et sa durée de protection sont supérieures à 85% et 30 ans, respectivement. D’un point de vue méthodologique, nous avons développé une procédure de calibration multivariée capable de quantifier l’incertitude paramétrique dans les modèles. Elle nous a permis de montrer l’importance de cette incertitude et la nécessité de la représenter dans les résultats. Pour finir, nous avons quantifié l’incertitude structurelle liée aux hypothèses de modélisation suivantes: immunité de groupe, immunité naturelle, durée des partenariats, groupement des génotypes VPH et fonctions de temps utilisées pour représenter le déclin de la protection vaccinale. Conclusion: Nous avons développé des modèles de complexité croissante, en parallèle avec les méthodes de calibration adéquates, afin de pouvoir suivre et répondre aux questions de santé publique du moment. Notre dernier modèle est présentement utilisé pour examiner l’impact de la vaccination sur les inégalités de santé et sera utilisé dans le futur pour évaluer le rapport de coût-efficacité des nouveaux vaccins et optimiser les programmes de dépistage. / Objective: The two main objectives of this thesis were to develop 1) mathematical models to predict the population-level impact of HPV vaccination in Canada, and 2) methods to quantify uncertainty around model predictions. Methods: We developed three mathematical models: 1) a static compartmental model of cervical cancer natural history (Model 1), 2) an individual-based dynamic model of HPV infection (Model 2), and 3) the first individual-based transmission-dynamic model of partnership formation and dissolution, and natural history of multi-type HPV infection and disease (anogenital warts, and cervical, anogenital and oropharyngeal cancers) (Model 3). For each model, an extensive fitting procedure was conducted, which identified multiple posterior parameter combinations (out of hundreds of thousands of prior parameter sets) that fit simultaneously highly stratified behavioral and epidemiologic data, taken from the literature, population-based datasets, and original studies. Parameter uncertainty was illustrated by presenting the median [10th; 90th percentiles] of predictions, using the posterior parameter combinations. Sensitivity analysis was conducted varying vaccine efficacy, duration of protection, coverage and vaccination strategies. Results: We provided the following evidence for HPV vaccination recommendations. Models 1-3 predicted that girls-only HPV vaccination can substantially reduce HPV-related burden of disease. Predictions were most sensitive to duration of vaccine protection. Model 3 predicted that the bivalent vaccine will be slightly more effective at preventing cervical cancer in the longer term. However, the quadrivalent vaccine will substantially reduce anogenital warts. Finally, the candidate nonavalent vaccine has the potential to produce substantial incremental benefits if its efficacy and duration of protection are at least 85% and 30 years, respectively. From a methodological point of view, we illustrated that parameter uncertainty surrounding HPV natural history parameters is important and must be presented when providing predictions to decision makers. Finally, we identified key structural assumptions that influence predictions: herd immunity, natural immunity, partnership duration, individual genotypes and vaccine waning function. Conclusion: We developed increasingly sophisticated HPV models and calibration techniques to keep track with the increasingly complex policy questions being asked. Our final model is being used to examine the impact of HPV vaccination on health inequalities, evaluate the cost-effectiveness of HPV vaccination, and optimize screening.

Les travailleuses du sexe (TS) constituent une population fortement à risque d’infections sexuellement transmissibles (IST), incluant le virus de l’immunodéficience humaine (VIH) et le virus du papillome humain (VPH). À notre connaissance, depuis 2009, aucune étude n’a été réalisée sur l’épidémiologie des IST/VIH chez les TS au Mali. Par ailleurs, nous n’avons aucune connaissance d’étude réalisée sur l’épidémiologie des infections à VPH dans cette population clé au Mali et au Bénin. Cette thèse avait pour objectifs de : (1) déterminer la prévalence du VIH et des autres IST ainsi que des facteurs associés à ces infections chez les TS à Bamako, Mali; (2) estimer la prévalence du VPH, la distribution de même que les facteurs associés aux infections à VPH à haut risque chez les TS à Bamako, Mali et à Cotonou, Bénin; et (3) estimer les taux d’incidence et de persistance des infections à VPH chez les TS dans les deux pays ainsi que les facteurs qui leur sont associés. Les objectifs 1 et 2 ont conduit à la réalisation d’études transversales, tandis que l’objectif 3 a nécessité une étude longitudinale d’un an avec trois visites : recrutement initial, visites de suivi à 6 et 12 mois. Les sites d’étude étaient Cotonou (Bénin) et Bamako (Mali). Des variables concernant les caractéristiques sociodémographiques, comportementales et antécédents gynécologiques ont été recueillies. Des statistiques descriptives ont été produites. Des modèles multivariés de régression log-binomiale et de Poisson ont été utilisés pour identifier les facteurs associés aux différentes issues. Au total 353 TS ont été recrutées au Mali, l’âge moyen était de 26,8 ans. Concernant l’objectif 1, la prévalence du VIH était de 20,4%, et 35,1% des TS avaient au moins une IST. Les facteurs significativement associés à l’infection au VIH étaient l’âge plus avancé (test de tendance, p < 0,0001), la durée du travail du sexe ≥ 6 ans, la non-scolarisation ainsi que des infections à gonocoque et à chlamydia (p < 0,05). Par ailleurs, le jeune âge (test de tendance, p = 0,018), le nombre de clients ≥ 10 au cours des sept derniers jours et l’infection au VIH taient significativement associés aux autres IST (p < 0,05). Pour ce qui est de l’objectif 2, les données sur le VPH étaient disponibles pour 659 TS (309 au Bénin et 350 au Mali). La prévalence globale du VPH était de 95,5% au Bénin et de 81,4% au Mali. Les trois types de VPH à haut risque les plus prévalents chez les TS au Bénin étaient les VPH-58, VPH-16 et VPH-52; cet ordre au Mali était VPH-16, VPH-51 et VPH-52. Au Bénin, les principaux facteurs associés aux VPH à haut risque étaient la pratique de la douche vaginale et l’infection gonococcique (p < 0,05), tandis qu’au Mali, la durée du travail du sexe < 1 an et l’infection à VIH étaient les facteurs prédominants (p < 0,05). En lien avec l’objectif 3, le taux de participation à la visite de 12 mois était de 51,6%, mais 68,6% des participantes ont eu au moins une visite de suivi (51 femmes n’ayant pas participé à la visite de suivi de 6 mois sont revenues à 12 mois). Les taux d’incidence les plus élevés ont été observés avec VPH-59, VPH-16 et VPH-35 (≥ 6,3 cas pour 1000 femmes-mois). Les principaux facteurs associés à l’incidence des infections à VPH à haut risque étaient la durée du travail du sexe ≤ 1 an et l’infection par le VIH (p < 0,05). Les taux de persistance à 12 mois les plus élevés ont été observés avec VPH-59, VPH-51/VPH-52 et VPH-35 (≥ 28,6%). Les facteurs de risque de persistance étaient l’âge des TS < 20 ans ou ≥ 50 ans (p < 0,05); les infections à VIH ou à chlamydia ainsi que l’infection avec de multiples types de VPH à l’inclusion (p < 0,05). En conclusion, les TS dans ces pays d’Afrique occidentale sont caractérisées par une prévalence élevée des IST/VIH, des taux élevés de prévalence, d’incidence et de persistance du VPH. Ces données impliquent la nécessité de revoir la conception des programmes de prévention des IST/VIH y compris le VPH chez les TS afin de prévenir le cancer du col utérin chez ces dernières et de briser la chaine de transmission de ces IST vers la population générale de ces pays. / Female sex workers (FWs) represent a high-risk group for sexually transmitted infections (STIs), including the human immunodeficiency virus (HIV), and the human papillomavirus (HPV). To our knowledge, since 2009, no study has been conducted on the epidemiology of HIV/STIs among FSWs in Mali. Also, there are no available data on the epidemiology of HPV infections in this key population in Mali and Benin.The objectives of this thesis were to (1) assess the prevalence of HIV/STIs and associated factors among FSWs in Bamako, Mali; (2) estimate HPV prevalence, distribution and factors associated with high-risk (HR) HPV infections in FSWs in Bamako (Mali) and Cotonou (Benin), and (3) estimate the incidence and persistence rates of HPV infections in FSWs in the two countries as well as factors related to both incidence and persistence of HR-HPV infections. Cross sectional studies were conducted for objectives 1 and 2, where as a longitudinal study with visits at three time points (baseline, follow-up visits at 6 months and at 12 months) were carried out for objective 3. It took place in Cotonou (Benin) and Bamako (Mali). Sociodemographic, behavioral and gynecological history data were collected. Descriptive statistics were computed. Multivariate log-binomial and Poisson regression models were used to identify factors associated with study outcomes. Overall, 353 FSWs were recruited in Mali; the mean age was 26.8 years. Concerning objective 1, HIV prevalence was 20.4% and 35.1% of FSWs had at least one STI. Factors significantly associated with HIV were older age (trend test, p < 0.0001), sex work duration ≥ 6 years, uneducated status, gonococcal and chlamydial infections (p < 0.05). In addition, younger age (trend test, p = 0.018), number of clients ≥10 during the past week, and HIV infection were significantly associated with other STIs (p < 0.05). Regarding objective 2, HPV data were available for 659 FSWs (309 in Benin and 350 in Mali). The overall HPV prevalence rates were 95.5% in Benin and 81.4% in Mali. The three most common HPV types among FSWs in Benin were HPV58, HPV16, and HPV52; this order was HPV16, HPV51, and HPV52 in Mali. In Benin, the main factors associated with HR-HPV infections were vaginal douching and gonococcal infection (p < 0.05), whereas in Mali, these factors were duration of sex work < 1 year and HIV infection (p < 0.05). Concerning objective 3, the 12-month participation rate was 51.6%, but retention for at least one follow-up visit was 68.6% (51 women not attending the 6-month follow-up visit came back at 12 months). The highest incidence rates of HR-HPV over 12 months occurred with HPV59, HPV16 and HPV35 (≥ 6.3 cases per 1000 women-months). Factors associated with HR-HPV incidence were sex work duration ≤ 1 year and HIV infection (p < 0.05). The highest HR-HPV persistence rates were observed for HPV59, HPV51/HPV52 and HPV35 (≥ 28.6%). Risk factors for HR-HPV persistence were age < 20 years or ≥ 50 years (p < 0.05); HIV and chlamydial infections as well as infection with multiple HPV types at baseline (p <0.05). In conclusion, FSWs in these West African countries are characterized by high HIV/STI prevalence, and by high rates of HPV prevalence, incidence and persistence. These data suggest the need to reconsider the conceptual framework of STI/HIV (including HPV) prevention programs aimed at FSWs in order to prevent cervical cancer among them and break the transmission chain of these STIs to the general population.

L’infection au papillomavirus humain (HPV) est connue pour être le principal facteur causal d’une série de maladies aussi bien bénignes (condylomatose ano-génitale, papillomatose lyringée, et autres) que malignes (cancer du col de l’utérus, certains cancers ORL, et autres). Deux vaccins prophylactiques (Gardasil® et Cervarix®) sont sur la marché depuis à peu près quatre ans pour prévenir cette infection. Le présent travail de thèse comportait trois objectifs principaux : i) étudier in-silico l’immunogénicité du vaccin Gardasil® ; ii) étudier in-silico l’histoire naturelle d’une infection à HPV et iii) évaluer in-silico le potentiel de l’hypothèse thérapeutique suivante : l’administration intramusculaire du vaccin Gardasil® chez des patients atteints d’une papillomatose laryngée induirait un effet bénéfique car l’arrivée des immunoglobulines au tissu affecté empêcherait l’HPV de compléter son cycle de vie et, par conséquent, la maladie de se propager. Les principales conclusions sont : i) pour qu’une papillomatose laryngée ne s’étende pas il faudrait, d’après nos simulations, que le taux d’IgGs sériques soit maintenu au-dessus de 200 mMU/mL ; ii) pour rester, sur une période de 10 ans, le plus longtemps possible au-dessus de ce seuil (d´effet thérapeutique), en administrant la quantité minimale de vaccin, il faudrait, d’après nos simulations, suivre le protocole suivant : l’immunisation de base (à 0, 2 et 6 mois), suivie de trois rappels successifs tous les six mois jusqu’au 24ème mois, suivis d’un rappel 18 mois plus tard ; iii) par ailleurs, il semble inutile (voire contreproductif), d’après nos simulations, de modifier le schéma traditionnel de base (0-2-6 mois) / Two prophylactic vaccines have demonstrated to prevent infections with the human papillomavirus (HPV). Thus, they have been in the market for the last four years, or so. The three main objectives of the present project were: i) to study in-silico the immunogenicity of one of these vaccines (Gardasil®); ii) to study in-silico the natural history of an HPV infection, and iii) to assess in-silico the potential of the following therapeutic hypothesis : the intramuscular administration of Gardasil® to patients already suffering from a recurrent respiratory papillomatosis would result in a better prognosis thanks to the fact that the HPV-specific immunoglobulins that would bathe the affected tissue would impede the virus to complete its life cycle and, therefore, the disease to progress. The main conclusions are: i) according to our simulations, the minimum serum IgG titer required for hampering the progression of a recurrent respiratory papillomatosis would be 200 mMU/mL ; ii) in order to keep, within a time window of ten years, the anti-HPV IgG titer over the just-mentioned therapeutic-effect threshold, the biggest possible fraction of time and through the administration of the smallest possible number of booster doses, it would be necessary, according to our simulations, to adopt the following vaccination schedule: the basic three doses (at months 0, 2 and 6), followed by three successive booster doses, every six months, until reaching the 24th month, followed by a late final booster dose, 18 months later. iii) incidentally, it would seem to be inappropriate, according to our simulations, to modify the original initial vaccination schedule (at months 0, 2 and 6)

High-risk mucosal human papillomaviruses (HPVs) are major aetiological agents for the development of cervical cancer. Thus, the current goal of cervical cancer treatment is to develop vaccines against HPV s. Such vaccines would either prevent cervical cancer by eliminating HPV infection or be useful for treating established lesions by the destruction of cells displaying HPV proteins. The aim of this thesis was to characterise immune responses to the E5 protein of HPV -16, one of several antigens with possible use in vaccination. To determine whether immune responses to HPV -16 E5 existed and whether they could be correlated with disease severity or with the presence of HPV -16 DNA, both cell mediated (Chapter Two) and humoral (Chapter Three) immunity was investigated in women with and without cervical disease. Cellular responses in a minority of women were inversely correlated with disease severity. However, E5 specific antibodies were negatively correlated with the absence of HPV -16 DNA. Thus, although some immune responses were evident, these were generally limited to a small number of subjects and were not associated with the detection of HPV-16 E5 mRNA or DNA sequence variants. Due to the immune responses in women, E5 was further investigated to determine if the absence of HPV -16 E5 specific immune responses was due to the poor antigenicity of HPV -16. Mice were immunised with synthetic peptides corresponding to full length HPV -16 E5 (Chapter Four). As with the human data, cellular responses and weak antibody responses were detected in mice. Some mice also exhibited cytotoxic T -lymphocyte responses and when E5/major histocompatibility class I (MHC-I) interactions were investigated, a number of peptides showed a high percentage of binding. The E5/MHC-I interactions were further investigated (Chapter Five). The surface expression of MHC-I on cells containing HPV-16 or -18 DNA was found to be lower than on HPV DNA negative cell lines even after stimulation with interferon-gamma. Stimulation with E5 synthetic peptides increased expression of cell surface MHC-I molecules on cell lines negative for HPV DNA. Furthermore, the presence of the E5 gene reduced the expression of the ovalbumin gene in normal human keratinocytes. In conclusion, the data contained within this thesis indicate that HPV-16 E5 CMI is inversely correlated with disease status. It is possible to induce cell mediated responses to HPV -16 E5 and low-titre antibody responses. The presence of HPV16 E5 DNA may impair normal cellular function.

This thesis examined the evidence, policy decision-making, and implementation of HPV vaccination in Canada as a case study to explore normalization versus individualized decision making in public health programs. Mixed methods were used: a systematic review, content analyses and policy document analysis. Overall, the scientific evidence supported an effect of vaccination against HPV infection and precancerous cervical lesions, but evidence regarding cervical cancer incidence or mortality is lacking. Scientific and medical communities appeared optimistic about the vaccine, but cautious about its readiness for routine implementation. Policy decision-making was initially cautious, but shifted towards active program implementation, possibly related to the availability of federal funding. The educational materials and media coverage both sent clearly normalizing messages about HPV vaccination. The discussion suggests that HPV vaccination might be more suited to an individualized than population approach, but many factors coincided to promote its implementation, in Canada, within a traditional public health model.

El cáncer de cuello uterino (CCU) es el segundo tipo de cáncer más común en el mundo, en Latinoamérica llega a ser el primer causante de mortalidad en algunos lugares y en el Perú es la principal causa de muerte por cáncer en mujeres de edad reproductiva debilitando el crecimiento de las familias y comunidades. El principal factor que lo provoca es el contagio por virus del papiloma humano (VPH); existe la vacuna contra este virus contribuyendo a la prevención del CCU. Objetivo: determinar el nivel de conocimiento y actitud frente a la vacuna contra el VHP en las adolescentes que pertenecen a las Instituciones Educativas del Centro Materno Infantil de Salud–Chorrillos II. Material y método: estudio de naturaleza cuantitativa, de diseño descriptivo y cohorte trasversal a realizarse en las Instituciones Educativas del Centro Materno infantil de Salud, en una muestra de 111 adolescentes, para recolectar los datos se utilizó la técnica de la encuesta con su instrumento el cuestionario elaborado por la investigadora, el cual fue sometido a juicio de expertos y a prueba piloto para su validez y confiabilidad respectivamente. Para el análisis de los datos se utilizó los estadígrafos para univariables teniendo en cuenta las medidas de tendencia central, asimismo la investigación fue evaluado por el comité de ética correspondiente al área de estudio. Resultados: el nivel de conocimiento frente a la vacuna contra el VPH es medio 60%, así como en sus dimensiones en generalidades del virus del papiloma humano 68% y respecto a la vacuna contra el virus del papiloma humano 59%; además no conocen acerca de las formas de transmisión 50% y síntomas 86%; mientras que conocen respecto a definición del VPH 86%, agente causal 61% y consecuencias 75%. No conocen acerca de la importancia 74% y reacciones adversas 65%; mientras que conocen respecto a edad de inicio de vacunación 86%, dosis 86% y lugar de aplicación 78%. La actitud frente a la vacuna contra el VPH es de indiferencia 60%, también de acuerdo a sus dimensiones cognitiva 68%, afectiva 69% y conductual 70%. Conclusiones: El nivel de conocimiento frente a la vacuna contra el VPH es medio y la actitud frente a la vacuna contra el VPH es de indiferencia.

Human papillomaviruses (HPV) are among the most common sexually transmitted infections and are responsible for 5% of all human cancers. HPV type 16 is the most prevalent of the high-risk HPVs (a subgroup of HPVs with potential to cause cancer), accounting for ~55% of HPV-associated cancers. HPV16 is a nonenveloped virus, composed of the major capsid protein L1, the minor capsid protein L2, and a circular double-stranded DNA genome (vDNA) condensed with human histones. HPV initially infects undifferentiated basal keratinocytes and viral replication is dependent on epithelial differentiation. Like many other DNA viruses, HPV must deliver its vDNA to the host cell nucleus to successfully replicate. Initial binding of HPV16 to host cells is through L1 interactions with cell surface heparan sulfate receptors. Shortly after virus binding, L2 is believed to undergo furin cleavage-dependent conformational changes, resulting in spanning of the protein across the local membrane and exposure of the central and C-terminal regions of L2 (which was lumenal and and inaccessible before furin cleavage) to the host cell cytosol. L2 is critical for transport of the L2/vDNA from endosomes to the trans-Golgi network (TGN). We hypothesize that furin-dependent early L2 spanning, through the direct binding and recruitment of cytosolic sorting factors, may contribute to viral endocytosis and subcellular retrograde trafficking (trafficking from endosomes to Golgi) of vDNA. We have developed a Tac receptor (CD25 or IL2 receptor, a transmembrane cell surface protein) chimera system to study L2-dependent endocytosis and trafficking. In this system the Tac ecto- and transmembrane domains are fused to the ~400 amino acid portion of L2 that is likely cytosolic upon L2 spanning. Through transient expression of Tac-L2 chimera we use anti-Tac ectodomain antibodies to label and track cell surface populations by immunofluorescence and confocal microscopy. We have also adopted this system to study endocytosis through a cell surface biotinylation approach. Both approaches suggest that L2 may enhance endocytosis and preliminary evidence suggests that the Tac-L2 chimera may recruit the cytosolic retromer complex (the host cytosolic factors help protein retrograde trafficking) to preferentially traffic to the TGN. Retromer-dependent trafficking of cargo from early endosomes to the TGN is known to involve certain members of the sorting nexin family, specifically the SNX-BAR proteins. We performed a small siRNA screen and identify SNX6 and SNX32 (aka SNX6b) as SNX-BAR proteins that may be specifically involved in retrograde trafficking of HPV16 L2/vDNA during infection. Future work will focus on the mechanisms through which L2 and SNX6 influence HPV16 entry and trafficking.

O câncer de cervical é causado por uma infecção persistente por algum dos tipos oncogênicos de Papilomavírus Humano (HPV) e continua a ser um problema de saúde pública, especialmente nos países em desenvolvimento. Por Peptide Phage Display, foram selecionadas sequências de peptídeos com afinidade de ligação a linhagens celulares ou a tumores associados ao HPV. Dentre elas, foi possível identificar sequências contidas em moléculas importantes para a progressão de tumores, como a -manosidase e triptase, enzimas que desempenham um papel importante na progressão tumoral. Para caracterizar o efeito da inibição de -manosidase II na terapia de tumores cervicais em camundongos, utilizamos a droga Swainsonina (SW), previamente descrita como inibidor desta enzima. Nós testamos o efeito desta droga tratando animais inoculados com células tumorais que expressam os oncogenes E6 e E7 de HPV16. Observamos que os animais tratados com Swainsonina apresentaram crescimento tumoral significativamente mais rápido do que os animais controle. Investigando os mecanismos por trás desse efeito, descobrimos que embora SW module parcialmente os macrófagos associados aos tumores, o tratamento induz o acúmulo de células com fenótipo mieloderivado supressor no baço dos animais, potencializando o efeito tolerogênico dos tumores sobre o sistema imune. Sendo assim, sugerimos cautela no uso deste fármaco para a terapia de pacientes com tumores HPV&#43. Outro braço do trabalho foi avaliar o papel da triptase, que é produzida por mastócitos, no infiltrado inflamatório. Para isto padronizamos um modelo de co-cultura de esferóides tumorais da linhagem TC-1 com a linhagem de mastócitos murinos PT18. Através deste modelo pudemos observar que a linhagem tumoral consegue induzir a desgranulação dos mastócitos independentemente de anticorpos. Além disso, quando em co-cultura, a linhagem tumoral parece estar aumentando a meia-vida dos mastócitos e estimulando a proliferação destes. Em experimentos in vivo observamos que tumores induzidos com as células PT18 e TC-1 cresceram mais rapidamente do que tumores induzidos apenas com TC-1. Através da imunofenotipagem dos tumores ficou evidenciado um aumento de células CD31+ e no infiltrado inflamatório total de tumores induzidos com o co-cultivo. Justificando o fato destes crescerem mais rapidamente, sugerindo que os mastócitos podem ter efeitos tanto proliferativos quanto no processo de angiogênese tumoral. / Cervical cancer is caused by a persistent infection by some of the oncogenic types of Human Papillomavirus (HPV) and continues to be a public health problem, especially in developing countries. By Peptide Phage Display peptide sequences were selected with binding affinity to cell lines or to HPV-associated tumors. Among them, it was possible to identify sequences contained in molecules important for the progression of tumors, such as -mannosidase and tryptase, enzymes that play an important role in tumor progression. To characterize the effect of -mannosidase II inhibition on cervical tumor therapy in mice, we used the drug Swainsonina (SW), previously described as an inhibitor of this enzyme. We tested the effect of this drug by treating animals inoculated with tumor cells expressing HPV16 E6 and E7 oncogenes. We observed that Swainsonine treated animals had significantly faster tumor growth than control animals. Investigating the mechanisms behind this effect, we found that although SW partially modulates tumor-associated macrophages, the treatment induces the accumulation of cells with suppressive myeloderivative phenotype in the animals spleens, enhancing the tolerogenic effect of tumors on the immune system. Therefore, we suggest caution in the use of this drug for the therapy of patients with HPV&#43 tumors. Another arm of the study was to evaluate the role of tryptase, which is produced by mast cells, in the inflammatory infiltrate. For this we standardized a co-culture model of tumor spheroids of the TC-1 lineage with the murine mast cell line PT18. Through this model we could observe that the tumoral lineage can induce mast cell degranulation independently of antibodies. In addition, when co-cultured, the tumoral lineage appears to be increasing the half-life of mast cells and stimulating the proliferation of these. In in vivo experiments we observed that tumors induced with PT18 and TC-1 cells grew faster than tumors induced only with TC-1. Tumor immunophenotyping revealed an increase in CD31&#43 cells and in the total inflammatory infiltrate of tumors induced with co-culture. Justifying the fact that they grow faster, suggesting that mast cells can have both proliferative effects and the process of tumor angiogenesis.

Thesis advisor: Junona Moroianu / The E7 protein of low risk HPV11 has been shown to interact with multiple proteins, including pRb, in both the cytoplasm and the nucleus. High risk HPV16 E7 and low risk HPV11 E7 share a novel nuclear import pathway independent of karyopherins but dependent on the GTPase Ran (Angeline, et al., 2003; Knapp, et al., 2009; Piccioli, et al., 2010). We continued to analyze the nucleocytoplasmic transport of HPV11 E7 in vivo through transfection assays in HeLa cells with EGFP-HPV11 E7 wild type and mutant fusion constructs. We found that nuclear localization of HPV11 E7 is mediated by a nuclear localization signal located in the C-terminal domain which contains a unique zinc-binding domain. Mutations of cysteine residues that interfered with zinc-binding clearly disrupted the nuclear localization of the EGFP-11cE7 and EGFP-11E7 mutants. These data suggest that the integrity of the zinc-binding domain is essential for the nuclear localization of HPV11 E7. In addition, we discovered that HPV11 E7 has a leucine-rich C-terminal nuclear export signal (NES) (76IRQLQDLLL84) mediating the nuclear export of HPV11 E7 in a CRM1-dependent manner. / Thesis (BS) — Boston College, 2011. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: Biology Honors Program. / Discipline: Biology.

A infecção genital pelo Papilomavírus Humano (HPV) é considerada a doença sexualmente transmissível mais freqüente em todo o mundo, representando importante problema de saúde pública devido à sua alta prevalência e transmissibilidade. Estima-se que cerca de 75% da população sexualmente ativa entre em contato com um ou mais tipos de HPV durante sua vida, com prevalência mais elevada entre mulheres jovens. Estudos epidemiológicos têm demonstrado que a infecção pelo vírus da imunodeficiência humana (HIV) está associada a elevadas prevalências da infecção pelo HPV. A literatura acerca da infecção pelo HPV em gestantes é escassa e controversa. O objetivo do trabalho foi identificar a prevalência da infecção pelo HPV em gestantes e identificar a possível influência da infecção pelo HIV-1 nesta prevalência. Foi realizada amostragem de pacientes do Ambulatório de Pré-natal do Setor de Moléstias Infecto-contagiosas e do Pré-natal de Baixo Risco do Departamento de Ginecologia e Obstetrícia do Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo. Todas as pacientes foram informadas sobre o estudo e assinaram o termo de consentimento livre e esclarecido. Foram coletados lavados cérvico-vaginais, que foram submetidos à extração do DNA utilizando a técnica de salting out. Realizou-se a detecção do HPV nas amostras de DNA através da técnica de reação em cadeia de polimerase (PCR), e as amostras positivas para o HPV foram testadas para os tipos 6, 11, 16 e 18. Foram arroladas ao todo 97 pacientes, sendo 44 portadoras do HIV e 53 sem esta infecção. Do total de pacientes avaliadas, 66 foram positivas para o HPV. A prevalência para a infecção pelo HPV foi de 79,5% e 58,5% nas pacientes portadoras ou não do HIV, respectivamente. A infecção pelo HIV aumentou o risco de ser portadora do HPV, principalmente do tipo oncogênico. Contagem de linfócitos T CD4+ abaixo de 200 células/mm3 e carga viral do HIV maior que 10000 cópias aumentaram o risco de infecção pelo HPV. Este estudo mostrou haver maior prevalência da infecção pelo HPV em grávidas portadoras do HIV, permitindo inferir que a infecção por esse retrovírus seja um fator de risco significativo para o aumento da infecção pelo HPV em gestantes. / Genital infection with human papillomavirus (HPV) is considered to be the most frequent sexually transmitted disease around the world, representing an important public health problem due to its high prevalence and transmissibility. It is estimated that 75% of the sexually active population gets in contact with one or more HPV types during their lives, with higher prevalence among younger women. Epidemiologic studies have demonstrated that human immunodeficiency virus (HIV) infection is associated with a high prevalence of HPV infection. The literature about HPV infection during pregnancy is scarce and controversial. The aim of this study was to estimate the prevalence of HPV infection in pregnant women and identify the possible influence of HIV-1 infection on this prevalence. Patients were selected from the Prenatal Outpatient Clinic of the Infectious Diseases Sector and from the Low-risk Prenatal Outpatient Clinic of the Obstetrics and Gynecology Department of the University Hospital, Medical School of Ribeirão Preto, São Paulo University. All patients were informed about the study and signed an informed consent term. Cervical-vaginal washes were collected and submitted to DNA extraction by the salting-out technique. HPV was detected in the DNA samples by the polymerase chain reaction (PCR) technique and the HPV-positive samples were tested for types 6, 11, 16 and 18. Ninety-seven patients were included in the study, 44 of them being HIV-positive and 53 HIV-negative. Of the patients evaluated, 66 were positive for HPV. The prevalence of HPV infection was 79.5% and 58.5% in HIV-positive and -negative women, respectively. HIV infection increased the risk of harboring HPV, mainly oncogenic types. A CD4+ T-cell count below 200 cells/mm3 and HIV viral load above 10000 copies/mL increased the risk of HPV infection. This study showed a higher prevalence of HPV infection in HIV-positive pregnant women, suggesting that this retrovirus infection is a significant risk factor for the increase of HPV infection in pregnant women.