46 research outputs found
Épidémiologie et immunité muqueuse spécifique au cours de l'infection à Papillomavirus Humains : implications pour la prévention des cancers associés
High-risk human papillomavirus (HR-HPV) [groups a7 (HPV-18, -45 and -68) and a9 (HPV-16, -31, -33, -35, -52 and - 58)] are the etiological agents of cervical cancer, which is now the first female cancer in several countries in sub-Saharan Africa. Our first objective was to build research hypotheses based on literature data, by writing two extensive reviews of the literature, one on cervical cancer in Africa, and the other on systemic and genital humoral immunity specific against HPV. Our second objective was to collect biological collections from clinical cohorts of Africans at risk for oncogenic HPV infection in sub-Saharan Africa (Central African Republic, Chad) and France (1st generation immigrant women). Our third goal was to acquire and transfer sophisticated techniques of medical virology (detection and genotyping of HPV by multiplex real-time PCR) and immunology [production of "virus-like particles" (VLPs) and development a serological test for the detection of systemic and mucosal immunoglobulins G against HR-HPV groups a7/a9]. Our fourth objective was to apply the acquired molecular techniques to describe the molecular epidemiology of HPV infection in cohorts of African individuals (Chadian women, African immigrant women living in France, Central African homosexual men) and to predict within these, the efficacy of multivalent prophylactic vaccination against HPV. In these cohorts we have demonstrated: i) particularly high prevalence of oncogenic HPV infections and HIV-1 infection; (ii) atypical molecular epidemiology of oncogenic HPV infections, with an HR-HPV distribution very different from that currently observed in developed countries; and lastly, iii) a potential predictive efficacy of prophylactic vaccination with Gardasil-9® nonavalent vaccine. Finally, our fifth and last objective was to apply the acquired immunological techniques ("VLP-based ELISA") to evaluate the immune response to systemic and mucosal IgG against HR-HPV of the a7/a9 groups, in order to build the immunological bases of the possibility of catch-up vaccination with prophylactic vaccines against oncogenic HPV in first-generation female African women living in France, who are at particularly high-risk of cervical cancer. We thus demonstrated the existence of 3 categories of women: a) a predominant category (2/3° of women) showing a genital HPV replication associated with a systemic and genital IgG immune response against most a7/a9 HPV targeted by Gardasil-9® vaccine, with cross-reactivities against most of the a7/a9 HPV antigens of interest, probably reflecting a history of multiple genital HPV infection episodes in addition to the current infection; this category of women could not a priori benefit from the multivalent prophylactic catch-up vaccination against oncogenic HPV; b) a second category (1/5°) showing a lack of genital HPV infection associated with a weak immune response to systemic and genital IgG directed only against the a9 HPV targeted by the Gardasil-9®; this category of women could possibly benefit from the catch-up vaccination against HPV; and finally (c) a third category (1/10°) showing a complete absence of genital HPV infection and a lack of systemic and genital IgG immune response against a7/a9 HPV targeted by Gardasil-9®; despite their advanced age, this category of women could benefit fully from prophylactic vaccination against HPV. This work allowed publishing 7 articles written in English (3 accepted, 4 submitted).Les papillomavirus humain (HPV) à haut-risque (HR-HPV) oncogène [groupes a7 (HPV-18, -45 et -68) et a9 (HPV-16, -31, -33, -35, -52 et -58)] sont les agents étiologiques du cancer du col de l'utérus, qui est désormais le premier cancer féminin dans plusieurs pays d'Afrique subsaharienne. Notre premier objectif a été de construire un corpus d'hypothèses de travail de recherche issus des données de la littérature, en rédigeant deux revues extensives de la littérature, l'une sur le cancer du col en Afrique, et l'autre sur l'immunité humorale systémique et muqueuse spécifique contre les HPV. Notre deuxième objectif a été de recueillir des collections biologiques à partir de cohortes cliniques d'individus Africains à risque d'infection à HPV oncogènes, en Afrique subsaharienne (République Centrafricaine; Tchad) et en France (femmes immigrées de 1° génération). Notre troisième objectif a été d'acquérir et de transférer des techniques sophistiquées de virologie médicale (détection et génotypage des HPV par PCR en temps réel multiplex) et d'immunologie [production de "virus-like particles" (VLP) et mise au point d'un test sérologique de détection des immunoglobulines systémiques et muqueuses contre les HR-HPV des groupes a7/a9]. Notre quatrième objectif a été d'appliquer les techniques moléculaires acquises afin de décrire l'épidémiologie moléculaire de l'infection à HPV de cohortes d'individus Africains inclus (femmes du Tchad; Africaines immigrées vivant en France; homosexuels masculins de Centrafrique) et de prédire au sein de celles-ci l'efficacité de la vaccination prophylactique multivalente contre les HPV. Nous avons ainsi démontré au sein de ces cohortes : i) des prévalences particulièrement élevées d'infections à HPV oncogènes et d'infection à VIH-1; ii) une épidémiologie moléculaire des infections à HPV oncogènes inédite, avec une distribution des HR-HPV très différente de celle connue dans les pays développés; et enfin iii) une efficacité prédictive potentielle de la vaccination prophylactique par le vaccin nonavalent Gardasil-9®. Enfin, notre cinquième et dernier objectif a été d'appliquer les techniques immunologiques acquises ("VLP-based ELISA") pour évaluer la réponse immunitaire à IgG systémique et muqueuse contre les HR-HPV des groupes a7/a9, dans le but de poser les bases immunologiques de la possibilité de vaccination de rattrapage par les vaccins prophylactiques contre les HPV oncogènes au sein des femmes Africaines immigrées de 1° génération vivant en France, qui sont à risque particulièrement élevé de cancer du col de l'utérus. Nous avons ainsi démontré l'existence de 3 catégories de femmes: a) une première catégorie majoritaire (2/3° des femmes) montrant une réplication génitale à HPV associée à une réponse immunitaire à IgG systémique et génitale contre la plupart des a7/a9 HPV ciblés par le vaccin Gardasil-9®, avec des réactivités croisées contre la plupart des antigènes des a7/a9 HPV d'intérêt, témoignant probablement d'antécédents de multiples épisodes infectieux génitaux à HPV en plus de l'infection actuelle; cette catégorie de femmes ne pourrait pas a priori bénéficier de la vaccination prophylactique multivalente de rattrapage contre les HPV oncogènes ; b) une deuxième catégorie (1/5°) montrant une absence d'infection génitale à HPV associée à une faible réponse immunitaire à IgG systémique et génitale dirigée uniquement contre les a9 HPV ciblés par le Gardasil-9®; cette catégorie de femmes pourrait éventuellement bénéficier de la vaccination de rattrapage contre les HPV; et enfin c) une troisième catégorie (1/10°) montrant une absence totale d'infection génitale à HPV et de réponse immunitaire à IgG systémique et génitale contre les a7/a9 HPV ciblés par le Gardasil-9®; malgré leur age avancé, cette catégorie de femmes pourrait bénéficier pleinement de la vaccination prophylactique contre les HPV. Ces travaux ont donné lieux à 7 publications rédigées en anglais (3 acceptées; 4 soumises)
Epidemiology and specific humoral immunity during human Papillomavirus infection : public health implications for the prevention of associated cancers
Les papillomavirus humain (HPV) à haut-risque (HR-HPV) oncogène [groupes a7 (HPV-18, -45 et -68) et a9 (HPV-16, -31, -33, -35, -52 et -58)] sont les agents étiologiques du cancer du col de l'utérus, qui est désormais le premier cancer féminin dans plusieurs pays d'Afrique subsaharienne. Notre premier objectif a été de construire un corpus d'hypothèses de travail de recherche issus des données de la littérature, en rédigeant deux revues extensives de la littérature, l'une sur le cancer du col en Afrique, et l'autre sur l'immunité humorale systémique et muqueuse spécifique contre les HPV. Notre deuxième objectif a été de recueillir des collections biologiques à partir de cohortes cliniques d'individus Africains à risque d'infection à HPV oncogènes, en Afrique subsaharienne (République Centrafricaine; Tchad) et en France (femmes immigrées de 1° génération). Notre troisième objectif a été d'acquérir et de transférer des techniques sophistiquées de virologie médicale (détection et génotypage des HPV par PCR en temps réel multiplex) et d'immunologie [production de "virus-like particles" (VLP) et mise au point d'un test sérologique de détection des immunoglobulines systémiques et muqueuses contre les HR-HPV des groupes a7/a9]. Notre quatrième objectif a été d'appliquer les techniques moléculaires acquises afin de décrire l'épidémiologie moléculaire de l'infection à HPV de cohortes d'individus Africains inclus (femmes du Tchad; Africaines immigrées vivant en France; homosexuels masculins de Centrafrique) et de prédire au sein de celles-ci l'efficacité de la vaccination prophylactique multivalente contre les HPV. Nous avons ainsi démontré au sein de ces cohortes : i) des prévalences particulièrement élevées d'infections à HPV oncogènes et d'infection à VIH-1; ii) une épidémiologie moléculaire des infections à HPV oncogènes inédite, avec une distribution des HR-HPV très différente de celle connue dans les pays développés; et enfin iii) une efficacité prédictive potentielle de la vaccination prophylactique par le vaccin nonavalent Gardasil-9®. Enfin, notre cinquième et dernier objectif a été d'appliquer les techniques immunologiques acquises ("VLP-based ELISA") pour évaluer la réponse immunitaire à IgG systémique et muqueuse contre les HR-HPV des groupes a7/a9, dans le but de poser les bases immunologiques de la possibilité de vaccination de rattrapage par les vaccins prophylactiques contre les HPV oncogènes au sein des femmes Africaines immigrées de 1° génération vivant en France, qui sont à risque particulièrement élevé de cancer du col de l'utérus. Nous avons ainsi démontré l'existence de 3 catégories de femmes: a) une première catégorie majoritaire (2/3° des femmes) montrant une réplication génitale à HPV associée à une réponse immunitaire à IgG systémique et génitale contre la plupart des a7/a9 HPV ciblés par le vaccin Gardasil-9®, avec des réactivités croisées contre la plupart des antigènes des a7/a9 HPV d'intérêt, témoignant probablement d'antécédents de multiples épisodes infectieux génitaux à HPV en plus de l'infection actuelle; cette catégorie de femmes ne pourrait pas a priori bénéficier de la vaccination prophylactique multivalente de rattrapage contre les HPV oncogènes ; b) une deuxième catégorie (1/5°) montrant une absence d'infection génitale à HPV associée à une faible réponse immunitaire à IgG systémique et génitale dirigée uniquement contre les a9 HPV ciblés par le Gardasil-9®; cette catégorie de femmes pourrait éventuellement bénéficier de la vaccination de rattrapage contre les HPV; et enfin c) une troisième catégorie (1/10°) montrant une absence totale d'infection génitale à HPV et de réponse immunitaire à IgG systémique et génitale contre les a7/a9 HPV ciblés par le Gardasil-9®; malgré leur age avancé, cette catégorie de femmes pourrait bénéficier pleinement de la vaccination prophylactique contre les HPV. Ces travaux ont donné lieux à 7 publications rédigées en anglais (3 acceptées; 4 soumises).High-risk human papillomavirus (HR-HPV) [groups a7 (HPV-18, -45 and -68) and a9 (HPV-16, -31, -33, -35, -52 and - 58)] are the etiological agents of cervical cancer, which is now the first female cancer in several countries in sub-Saharan Africa. Our first objective was to build research hypotheses based on literature data, by writing two extensive reviews of the literature, one on cervical cancer in Africa, and the other on systemic and genital humoral immunity specific against HPV. Our second objective was to collect biological collections from clinical cohorts of Africans at risk for oncogenic HPV infection in sub-Saharan Africa (Central African Republic, Chad) and France (1st generation immigrant women). Our third goal was to acquire and transfer sophisticated techniques of medical virology (detection and genotyping of HPV by multiplex real-time PCR) and immunology [production of "virus-like particles" (VLPs) and development a serological test for the detection of systemic and mucosal immunoglobulins G against HR-HPV groups a7/a9]. Our fourth objective was to apply the acquired molecular techniques to describe the molecular epidemiology of HPV infection in cohorts of African individuals (Chadian women, African immigrant women living in France, Central African homosexual men) and to predict within these, the efficacy of multivalent prophylactic vaccination against HPV. In these cohorts we have demonstrated: i) particularly high prevalence of oncogenic HPV infections and HIV-1 infection; (ii) atypical molecular epidemiology of oncogenic HPV infections, with an HR-HPV distribution very different from that currently observed in developed countries; and lastly, iii) a potential predictive efficacy of prophylactic vaccination with Gardasil-9® nonavalent vaccine. Finally, our fifth and last objective was to apply the acquired immunological techniques ("VLP-based ELISA") to evaluate the immune response to systemic and mucosal IgG against HR-HPV of the a7/a9 groups, in order to build the immunological bases of the possibility of catch-up vaccination with prophylactic vaccines against oncogenic HPV in first-generation female African women living in France, who are at particularly high-risk of cervical cancer. We thus demonstrated the existence of 3 categories of women: a) a predominant category (2/3° of women) showing a genital HPV replication associated with a systemic and genital IgG immune response against most a7/a9 HPV targeted by Gardasil-9® vaccine, with cross-reactivities against most of the a7/a9 HPV antigens of interest, probably reflecting a history of multiple genital HPV infection episodes in addition to the current infection; this category of women could not a priori benefit from the multivalent prophylactic catch-up vaccination against oncogenic HPV; b) a second category (1/5°) showing a lack of genital HPV infection associated with a weak immune response to systemic and genital IgG directed only against the a9 HPV targeted by the Gardasil-9®; this category of women could possibly benefit from the catch-up vaccination against HPV; and finally (c) a third category (1/10°) showing a complete absence of genital HPV infection and a lack of systemic and genital IgG immune response against a7/a9 HPV targeted by Gardasil-9®; despite their advanced age, this category of women could benefit fully from prophylactic vaccination against HPV. This work allowed publishing 7 articles written in English (3 accepted, 4 submitted)
In vitro inhibitory activity against HPV of the monoterpenoid zinc tetra-ascorbo-camphorate
Zinc tetra-ascorbo-camphorate (or drug “C14”) is a synthetic monoterpenoid derivative that has potent anti-HIV-1 activity in vitro. In this study, we evaluated the in vitro antiviral properties of C14 against human papillomavirus (HPV). Inhibition assay of HPV-16-pseudovirus (PsVs) adsorption on COS-7 cells by C14 was used. C14 inhibited HPV-16-PsVs adsorption with IC50 ranging between 2.9 and 8.3 μM and therapeutic indexes between >410 to >3,300. Pretreatment of COS-7 cells with C14 before addition of HPV-16-PsV was associated with more potent anti-HPV activity than simultaneous deposition on COS-7 of HPV-16-PsV and C14, suggesting that C14 is more effective in preventing HPV attachment to target cells than post-HPV adsorption viral events. Overall, these in vitro studies suggest that the monoterpenoid zinc tetra-ascorbo-camphorate molecule may be suitable for further clinical evaluations as potential microbicide or therapeutic drug
Cannabinoids and Chronic Liver Diseases
Nonalcoholic fatty liver disease (NAFLD), alcohol-induced liver disease (ALD), and viral hepatitis are the main causes of morbidity and mortality related to chronic liver diseases (CLDs) worldwide. New therapeutic approaches to prevent or reverse these liver disorders are thus emerging. Although their etiologies differ, these CLDs all have in common a significant dysregulation of liver metabolism that is closely linked to the perturbation of the hepatic endocannabinoid system (eCBS) and inflammatory pathways. Therefore, targeting the hepatic eCBS might have promising therapeutic potential to overcome CLDs. Experimental models of CLDs and observational studies in humans suggest that cannabis and its derivatives may exert hepatoprotective effects against CLDs through diverse pathways. However, these promising therapeutic benefits are not yet fully validated, as the few completed clinical trials on phytocannabinoids, which are thought to hold the most promising therapeutic potential (cannabidiol or tetrahydrocannabivarin), remained inconclusive. Therefore, expanding research on less studied phytocannabinoids and their derivatives, with a focus on their mode of action on liver metabolism, might provide promising advances in the development of new and original therapeutics for the management of CLDs, such as NAFLD, ALD, or even hepatitis C-induced liver disorders
Infrequent detection of human papillomavirus infection in head and neck cancers in the Central African Republic: a retrospective study
Abstract We carried out a retrospective study on the prevalence of HPV and genotype distribution by nested PCR and nucleotide sequencing analysis, in formalin-fixed, paraffin-embedded biopsies of 135 head and neck cancers (HNC) and 29 cervical cancers received between 2009 and 2017 for diagnosis at the Laboratoire National de Biologie Clinique et de Santé Publique of Bangui, the capital city of the Central African Republic. One oropharyngeal squamous cell carcinoma sample was positive for HPV type 16. The overall HPV prevalence in HNC biopsies was 0.74% (95% CI: 0.0–2.2). Among the 29 cervical cancer samples, 19 (65.5%; 95% CI: 48.2–82.8) were positive for HPV. These results indicate that HNC are infrequently associated with HPV infection in the Central African Republic
Acceptability, feasibility, and individual preferences of blood-based HIV self-testing in a population-based sample of adolescents in Kisangani, Democratic Republic of the Congo.
BACKGROUND:Adolescents living in sub-Saharan Africa constitute a vulnerable population at significant risk of HIV infection. This study aims to evaluate the acceptability, feasibility, and accuracy of home-based, supervised HIV self-testing (HIVST) as well as their predictors among adolescents living in Kisangani, Democratic Republic of the Congo (DRC). METHODS:A cross-sectional, door-to-door survey using a blood-based HIV self-test and a peer-based supervised HIVST approach was conducted from July to August 2018 in Kisangani, DRC. The acceptability and feasibility of HIVST were assessed among adolescents' consenting to use and interpret HIV self-test. The accuracy of HIVST was estimated by the sensibility and specificity of adolescent-interpreted HIV self-test. Factors associated with acceptability and feasibility of HIVST were analyzed with logistic regression. RESULTS:A total of 628 adolescents (including 369 [58.8%] females) aged between 15 and 19 years were enrolled. Acceptability of HIVST was high (95.1%); 96.1% of participants correctly used the self-test, and 65.2% asked for verbal instructions. The majority of adolescents (93.5%) correctly interpreted their self-test results. The Cohen's κ coefficient between the results read by adolescents and by supervisors was 0.62. The correct interpretation decreased significantly when adolescents had no formal education or attended primary school as compared to those currently attending university (37.0% versus 100%; adjusted OR: 0.01 [95% CI: 0.004-0.03]). In the hands of adolescents at home, the sensitivity of the Exacto Test HIV Self-test was estimated at 100%, while its specificity was 96.0%. The majority of participants (68.0%) affirmed that post-test counseling was essential, and that face-to-face counseling (78.9%) was greatly preferred. CONCLUSIONS:Home-based, supervised HIVST using a blood-based self-test and peer-based approach can be used with a high degree of acceptability and feasibility by adolescents living in Kisangani, DRC. Misinterpretation of test results is challenging to obtaining good feasibility of HIVST among adolescents with poor educational level. Face-to-face post-test counseling seems to be preferred among Kisangani's adolescents
Natural and vaccine-induced B cell-derived systemic and mucosal humoral immunity to human papillomavirus
International audienceIntroduction: Human papillomavirus (HPV) are the causative agent of mucosal neoplasia. Both cervical, anal and oropharyngeal cancers incidence is constantly increasing, making the HPV infection, a significant worldwide concern. Together, the CD8+ T cytotoxic cell-mediated response and the HPV-specific antibody response control most of the HPV infections before the development of cancers. Areas covered: We searched the MEDLINE and EMBASE databases and identified 228 eligible studies from 1987 to 2019 which examines both naturally acquired and vaccine induced humoral immunity against HPV infection in female and male subjects from worldwide origin. Herein, we synthesize current knowledge on the features of systemic and mucosal humoral immunity against HPV. We discuss the issues of the balance between the viral clearance or the escape to the host immune response, the differences between natural and vaccine-induced HPV-specific antibodies and their neutralizing capability. We also discuss the protection afforded after natural infection or following prophylactic vaccination. Expert opinion: Understanding the antibody response induced by HPV infection has led to the design of first-generation prophylactic vaccines. Now, prophylactic vaccination induces protective and long-lasting antibody response which would also strengthened the natural moderate humoral response in people previously exposed to the virus
Performance evaluation of the touchscreen-based Muse™ Auto CD4/CD4% single-platform system for CD4 T cell numeration in absolute number and in percentage using blood samples from children and adult patients living in the Central African Republic
Abstract Background The new microcapillary and fluorescence-based EC IVD-qualified Muse™ Auto CD4/CD4% single-platform assay (EMD Millipore Corporation, Merck Life Sciences, KGaA, Darmstadt, Germany) for CD4 T cell numeration in absolute number and in percentage was evaluated using Central African patients’ samples compared against the reference EC IVD-qualified BD FACSCount (Becton–Dickinson, USA) flow cytometer. Methods EDTA-blood samples from 124 adults, 10 adolescents, 13 children and 3 infants were tested in parallel at 2 reference laboratories in Bangui. Results The Muse™ technique was highly reproducible, with low intra- and inter-run variabilities less than 15%. CD4 T cell counts of Muse™ and BD FACSCount in absolute number and percentage were highly correlated (r2 = 0.99 and 0.98, respectively). The mean absolute bias between Muse™ and BD FACSCount cells in absolute number and percentage were −5.91 cells/µl (95% CI −20.90 to 9.08) with limits of agreement from −77.50 to 202.40 cells/µl, and +1.69 %CD4 (95% CI ±1.29 to +2.09), respectively. The percentages of outliers outside the limits of agreement were nearly similar in absolute number (8%) and percentage (10%). CD4 T cell counting by Muse™ allowed identifying the majority of individuals with CD4 T cell <200, <350 or <750 cells/µl corresponding to the relevant thresholds of therapeutic care, with sensitivities of 95.5–100% and specificities of 83.9–100%. Conclusions The Muse™ Auto CD4/CD4% Assay analyzer is a reliable alternative flow cytometer for CD4 T lymphocyte enumeration to be used in routine immunological monitoring according to World Health Organization recommendations in HIV-infected adults as well as children living in resource-constrained settings
Serum and cervicovaginal IgG immune responses against α7 and α9 HPV in non-vaccinated women at risk for cervical cancer: Implication for catch-up prophylactic HPV vaccination
International audienceBackground: Cervical cancer associated with high risk-human papillomavirus (HR-HPV) infection is becoming the one of the most common female cancer in many sub-Saharan African countries. First-generation immigrant African women living in Europe are at-risk for cervical cancer, in a context of social vulnerability, with frequent lack of cervical cancer screening and HPV vaccination.Objective: Our objective was to address immunologically the issue of catch-up prophylactic HPV vaccination in first-generation African immigrant women living in France.Methods: IgG immune responses and cross-reactivities to α7 (HPV-18, -45 and -68) and α9 (HPV-16, -31, -33, -35, -52 and -58) HPV types, including 7 HR-HPV targeted by the Gardasil-9® prophylactic vaccine, were evaluated in paired serum and cervicovaginal secretions (CVS) by HPV L1-virus-like particles-based ELISA. Genital HPV were detected by multiplex real time PCR (Seegene, Seoul, South Korea).Results: Fifty-one immigrant women (mean age, 41.7 years; 72.5% HIV-infected) were prospectively included. More than two-third (68.6%) of them carried genital HPV (group I) while 31.4% were negative (group II). The majority (90.2%) exhibited serum IgG to at least one α7/α9 HR-HPV. Serum HPV-specific IgG were more frequently detected in group I than group II (100% versus 68.7%; P = 0.002). The distribution of serum and genital HPV-specific IgG was similar, but mean number of IgG reactivities to α7/α9 HR-HPV was higher in serum than CVS (5.6 IgG per woman in serum versus 3.2 in CVS; P<0.001). Rates of IgG cross-reactivities against HPV different from detected cervicovaginal HPV were higher in serum and CVS in group I than group II. Finally, the majority of groups I and II women (68.6% and 68.7%, respectively) exhibited serum or cervicovaginal IgG to Gardasil-9® HR-HPV, with higher mean rates in group I than group II (6.1 Gardasil-9® HR-HPV per woman versus 1.4; P<0.01). One-third (31.2%) of group II women did not show any serum and genital HPV-specific IgG.Conclusions: Around two-third of first-generation African immigrant women living in France showed frequent ongoing genital HPV infection and high rates of circulating and genital IgG to α7/α9 HPV, generally cross-reacting, avoiding the possibility of catch-up vaccination. Nevertheless, about one-third of women had no evidence of previous HPV infection, or showed only low levels of genital and circulating HR-HPV-specific IgG and could therefore be eligible for catch-up vaccination