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IntroductionOne anastomosis gastric bypass (OAGB) has become a widespread technique over the last few years in France, without any prior assessment and despite existing controversies among bariatric surgeons. An older bypass technique for treating obesity, the Roux-en-Y gastric bypass (RYGB), is available and reimbursed, having been assessed and approved for use in 2005. In 2019, the French Haute Autorité de Santé (HAS) assessed OAGB for the treatment of severe and massive obesity. This assessment, the first in the world, was undertaken for OAGBs carried out with a 200- or 150-centimeter biliopancreatic-limb (BP-limb) length.MethodsA systematic review (SR) of the literature and consultation of a working group consisting of both healthcare professionals (clinician and surgeons) and patients were carried out. The primary aim of our assessment was to determine whether the OAGB technique can replace RYGB. The efficacy and safety profile of OAGB was compared with RYGB in adult patients with massive, severe obesity. Complications and postoperative follow up specific to OAGB were identified.ResultsThe three selected randomized controlled trials (RCTs) could not confirm the superiority or the non-inferiority of OAGB, compared with RYGB, on the selected efficacy endpoints of weight loss, resolution of comorbidities, and quality of life. Adverse events reported for OAGB included severe nutritional complications and bile reflux that could potentially lead to lower esophageal cancer. In one RCT, the frequency of serious adverse events in the OAGB group was almost two times higher than in the RYGB group.ConclusionsHAS considered that OAGB carried out with a longer (200 centimeter) BP-limb is not a validated technique for the surgical treatment of massive, severe obesity. Thus, it cannot be considered an alternative to RYGB. There were insufficient data available on OAGB performed with a 150-centimeter BP-limb. Thus, HAS recommended undertaking a multicenter RCT to assess the efficacy and safety of OAGB. Patients who have already undergone OAGB should receive the same follow up as patients who have received RYGB, including close monitoring for nutritional complications and lower esophageal cancer and an endoscopic examination five years after surgery.

Resume L’evaluation des technologies de sante (ETS) est en pleine evolution et l’interet de prendre en compte des domaines non cliniques est croissant. Si l’aspect medico-economique est communement reconnu, l’evaluation de l’impact organisationnel n’a pas ete autant etudiee. L’objet de ce travail etait de proposer une definition de l’impact organisationnel dans le secteur du dispositif, d’en delimiter les contours et d’explorer les methodes d’evaluation propres a ce domaine. Apres une analyse de la litterature relative a l’impact des technologies sur les organisations et de la litterature medicale, ainsi qu’une revue des textes reglementaires s’y rapportant, le groupe d’experts a identifie 12 types d’impact organisationnel. Plusieurs dispositifs medicaux ont ete passes au crible de cette grille de criteres qui s’est revelee discriminante et operante. Le groupe a ensuite degage de l’analyse de la pratique et des methodes decrites, quelques lignes directrices pour mener a bien l’evaluation de l’impact organisationnel. Ce travail montre que la prise en compte de l’impact organisationnel peut s’averer essentielle en complement des autres criteres privilegies actuellement (cliniques et economiques). Reste a lui trouver une place dans la decision et qui tienne compte du principe d’economicite.

Medical devices (MDs) cover a wide variety of products. They accompany changes in medical practice in step with technology innovations. Innovations in the field of MDs can improve the conditions of use of health technology and/or modify the organisation of care beyond the strict diagnostic or therapeutic benefit for the patients. However, these non purely clinical criteria seem to be only rarely documented or taken into account in the assessment of MDs during reimbursement decisions at national level or for formulary listing by hospitals even though multidimensional models for the assessment of health technologies have been developed that take into account the views of all stakeholders in the healthcare system In this article, after summarising the background concerning the assessment of health technologies in France, a definition of non-clinical criteria for the assessment of MDs is proposed and a decision tree for the assessment of MDs is described. Future lines of approach are proposed as a conclusion.

Resume Les dispositifs medicaux (DM) couvrent une large variete de produits. Ils accompagnent, au gre des innovations technologiques, l’evolution des pratiques medicales. Les innovations dans le champ du DM peuvent ameliorer les conditions d’utilisation de la technologie de sante et/ou modifier l’organisation des soins au-dela du strict benefice therapeutique ou diagnostique pour le patient. Cependant, ces criteres non purement cliniques semblent n’etre que rarement documentes ou pris en compte dans l’evaluation des DM lors des decisions de remboursement au niveau national ou de referencement au niveau des etablissements de sante alors meme que des modeles d’evaluation multidimensionnelle des technologies de sante, prenant en compte le point de vue de l’ensemble des acteurs du systeme de sante, ont ete elabores. Dans cet article, apres avoir rappele le contexte de l’evaluation des technologies de sante en France, une definition des criteres d’evaluation non clinique des DM est proposee et un arbre de decision pour l’evaluation des DM est decrit. Des pistes de reflexion sont proposees en conclusion.

Resume Le dispositif medical se caracterise notamment par une grande heterogeneite (de l’abaisse langue a la prothese de hanche, en passant par le dispositif non implantable a invasif), un cycle de vie court des produits avec des innovations incrementales recurrentes (de 18 mois a 5 ans) et un caractere operateur dependant. L’objet de cette table ronde etait de faire des propositions et recommandations sur les prerequis necessaires pour repondre aux attentes des autorites competentes francaises lors de demande d’etudes post-inscriptions des dispositifs medicaux (DM) necessaires en cas d’incertitude sur leurs consequences a court ou long terme. Ces etudes, sous la responsabilite du fabricant ou du distributeur du DM, visent a confirmer en vie reelle la place du DM dans la strategie therapeutique. Ce sont pres de 150 etudes post-inscriptions, concernant principalement des dispositifs de classe III, qui sont en cours et, pour la majorite, confrontees a des difficultes de mise en place ou d’atteinte des objectifs fixes par les autorites competentes. Devant ces constats, la table ronde s’est donc attachee a identifier precisement les conditions de mise en œuvre des etudes post-inscriptions specifiques aux caracteristiques des dispositifs medicaux. Des axes de progres sont envisageables pour ameliorer la realisation des etudes, et par consequent, l’efficience de la prise en charge des dispositifs medicaux par l’Assurance maladie : permettre aux industriels d’anticiper au mieux les demandes d’etudes post-inscriptions, definir un objectif principal unique par etude, integrer une phase de concertation sur le protocole des etudes entre les industriels, les autorites competentes et le comite scientifique, et enfin, sensibiliser et former les professionnels de sante a l’impact des etudes cliniques post-inscriptions dans la prise en charge du dispositif medical par l’assurance maladie.

Resume Le dispositif medical se caracterise par une grande heterogeneite (de l’abaisse langue a l’equipement d’imagerie, en passant par le dispositif implantable ou invasif), un cycle de vie court des produits avec des innovations incrementales recurrentes (de 18 mois a 5 ans) et un caractere operateur dependant : le plus souvent l’utilisateur clinicien doit realiser un acte de pose (prothese de hanche, stimulateur cardiaque), un acte therapeutique qui utilise un dispositif invasif non implantable (sonde d’ablation d’un foyer arythmique, ballonnet d’angioplastie, systeme de spondyloplastie par extension) voire un acte de suivi des dispositifs actifs implantes (suivi au long court des patients beneficiant d’un defibrillateur cardiaque, ou des malades parkinsoniens implantes d’un systeme de stimulation cerebrale profonde). La table ronde a souhaite se concentrer sur les procedures d’evaluation scientifique des dispositifs medicaux et des actes associes en vue de leur tarification et financement par l’Assurance maladie. Elle a ainsi pose pour postulat que le corpus de donnees disponibles etait suffisant et compatible avec une evaluation scientifique du benefice clinique. Les etudes post-inscription, qui participent a la continuite de l’evaluation des dispositifs medicaux, n’ont pas ete abordees. En outre, elle a choisi de centrer ses reflexions sur les dispositifs utilises dans les etablissements de sante (ES), les plus representatifs de l’association entre dispositifs et actes medicaux techniques. Le contexte des multiples procedures reglementaires, permettant la prise en charge des dispositifs medicaux et des actes, est rappele. Les problematiques liees plus specifiquement aux actes eux-memes, aux dispositifs medicaux non implantes et aux dispositifs medicaux innovants sont ensuite developpees. Dans chacune des trois situations, les propositions et les points de discussion de la table ronde sont presentes.

Introduction:The Health Technology Assessment (HTA) of esthetic procedures was performed by the French National Authority for Health (HAS), at the request of the French Ministry of Health (MoH), and under a new regulatory framework enabling the government to ban esthetic procedures considered harmful or potentially harmful to patients and consumers by HAS. Objectives: Describe HAS’ seven year experience with the safety assessment of four esthetic procedures.Methods:This is an HAS review of its methods used in four HTAs for the following evaluated techniques: lipolysis; cryolipolysis; esthetic mesotherapy; and, ultraviolet (UV) radiation in tanning devices. The review aimed to describe how these assessments have been undertaken and information sources used, from 2010 to 2017, to appreciate the safety profile of these procedures.Results:A systematic literature review (SRL) and analysis was performed for all four HTAs. Since findings did not allow for thorough appreciation of safety, additional sources of information were consulted to address evidence gaps. Sources may have included any combination of the following: i) National and international health care authority data and alerts ii) Legal and ethical frameworks iii) Public consultation iv) Expert opinion v) Patient-consumer association opinion vi) Economic analysisConclusions:An adaptation of the HTA methodology was necessary to meet the specific requirements of these assessments. Despite sources accumulated and consulted within the seven year period, quantitative data were found insufficient to fully appreciate the safety profile for any one of the studied esthetic procedures. National regulatory reinforcement on the reporting of adverse events, with implementation of a centralized online tool, is expected to generate and capture reliable data on the frequency and severity of adverse events associated with esthetic procedures. Recent European Union (EU) regulatory requirements on the safety and performance of medical devices include equipment used for esthetic procedures, indicating agreement and alignment on national and EU-level monitoring efforts.

Background: Generation of additional evidence may be necessary to access new promising technologies (marketing approval or coverage). Access with evidence generation (AEG) is a more recent concept with regard to coverage than to marketing approval.Objectives: One aim of Work Package 7 (WP7) Strand A of the European network for Health Technology Assessment (EUnetHTA) was to provide an overview of national AEG mechanisms associated with marketing approvals and funding or coverage decisions.Methods: A systematic literature review, surveys of WP7 Partners, and consultation of key people were used to obtain information on the AEG mechanisms used by twenty-three countries (twenty European countries, United States, Canada [Ontario], and Australia).Results: Interest in the implementation of AEG policies, particularly at the coverage decision stage, is growing. An overview of national experiences was used to draw up a generally applicable five-step policy framework for AEG mechanisms that comprised (i) a first assessment identifying knowledge gaps; (ii) a decision conditional to evidence generation; (iii) generation of the evidence requested; (iv) re-assessment integrating the new evidence; (v) a revised decision. The critical factors for success that were identified were coordination, methodological guidance, funding, and a regulatory framework. Countries were categorized on the basis of current implementation of the proposed policy framework.Conclusions: International collaboration is necessary to gather a critical mass of high-quality data quickly and to ensure timely access to new promising technologies. The overview produced by WP7A has led to development of tools to facilitate collaboration on evidence generation.

Heterosexual contact is the primary mode of human immunodeficiency virus (HIV) type 1 (HIV-1) transmission worldwide. The chemokine receptor CCR5 is the major coreceptor that is associated with the mucosal transmission of R5-tropic HIV-1 during sexual intercourse. The CCR5 molecule is thus a target for antibody-based therapeutic strategies aimed at blocking HIV-1 entry into cells. We have previously demonstrated that polyreactive natural antibodies (NAbs) from therapeutic preparations of immunoglobulin G and from human breast milk contain NAbs directed against CCR5. Such antibodies inhibit the infection of human macrophages and T lymphocytes by R5-tropic isolates of HIV in vitro. In the present study, we demonstrate that human immunoglobulins from the cervicovaginal secretions of HIV-seronegative or HIV-seropositive women contain NAbs directed against the HIV-1 coreceptor CCR5. Natural affinity-purified anti-CCR5 antibodies bound to CCR5 expressed on macrophages and dendritic cells and further inhibited the infection of macrophages and dendritic cells with primary and laboratory-adapted R5-tropic HIV but not with X4-tropic HIV. Natural anti-CCR5 antibodies moderately inhibited R5-tropic HIV transfer from monocyte-derived dendritic cells to autologous T cells. Our results suggest that mucosal anti-CCR5 antibodies from healthy immunocompetent donors may hamper the penetration of HIV and may be suitable for use in the development of novel passive immunotherapy regimens in specific clinical settings of HIV infection.

International audience; Health technology assessment (HTA) is a rapidly developing area and the value of taking non-clinical fields into consideration is growing. Although the health-economic aspect is commonly recognised, evaluating organisational impact has not been studied nearly as much. The goal of this work was to provide a definition of organisational impact in the sector of medical devices by defining its contours and exploring the evaluation methods specific to this field. Following an analysis of the literature concerning the impact of technologies on organisations as well as the medical literature, and also after reviewing the regulatory texts in this respect, the group of experts identified 12 types of organisational impact. A number of medical devices were carefully screened using the criteria grid, which proved to be operational and to differentiate properly. From the analysis of the practice and of the methods described, the group was then able to derive a few guidelines to successfully evaluate organisational impact. This work shows that taking organisational impact into consideration may be critical alongside of the other criteria currently in favour (clinically and economically). What remains is to confer a role in the decision-making process on this factor and one that meets the economic efficiency principle.

The ability of macrophages to adapt to changing cytokine environments results in the dominance of a particular functional phenotype of macrophages, which would play a significant role in HIV pathogenesis. In comparison with untreated macrophages (M0), we examined the role of macrophages derived from IFN-γ-activated monocytes (M1) in the HIV spread. We show that M0 and M1 bind with the same efficiency HIV-1 with a predominant role of C-type lectins in the R5-HIV attachment and of the heparan sulfate proteoglycans in the X4-HIV attachment. Despite similar levels of R5- and X4-HIV DNA, M1 replicates and weakly transmits the virus to activated T cells by releasing CXCR4- and CCR5-interacting chemokines. The blockade of dendritic cell-specific ICAM-3-grabbing nonintegrin expressed on M1 by mAb does not interfere with the viral transfer. Uninfected M1 recruits HIV-sensitive T cells efficiently and releases soluble factors, enhancing the viral production by these recruited cells. This study highlights the role of IFN-γ to induce a population of macrophages that archive HIV-1 within a latent stage and cause the persistence of the virus by favoring the recruitment of T cells or enhancing the viral replication in infected CD4+ T cells.

We previously demonstrated that GM-CSF/IFN-α combination allowed the differentiation of monocytes from HIV-infected patients into dendritic cells (DCs) exhibiting high CD8+ T cell stimulating abilities. The present study was aimed at characterizing the ability of DCs generated in the presence of GM-CSF and IFN-α to induce CD4 T cell responses. DCs were generated from monocytes of HIV-infected patients in the presence of GM-CSF with either IFN-α (IFN-DCs) or IL-4 (IL-4-DCs) for 7 days. Eleven patients receiving highly active antiretroviral therapy and exhibiting CD4 cell counts above 400/mm3 and plasma HIV-RNA

Medical devices are characterized notably by a wide heterogeneity (from tongue depressors to hip prostheses, and from non-implantable to invasive devices), a short life cycle with recurrent incremental innovations (from 18 months to 5 years), and an operator-dependent nature. The objective of the current round table was to develop proposals and recommendations concerning the prerequisites needed in order to meet the French health authorities expectations concerning requests for post-approval studies for medical devices, required in cases where short and long-term consequences are unknown. These studies, which are the responsibility of the manufacturer or the distributor of the medical device, are designed to confirm the role of the medical device in the therapeutic management strategy in a real-life setting. There are currently approximately 150 post-approval studies underway, mainly concerning class III devices, and the majority face difficulties implementing the study or meeting the study objectives. In light of this, the round table endeavored to clearly identify the conditions for implementation of post-approval studies specific to the characteristics of medical devices. Various areas of progress have been envisaged to improve the performance of these studies, and by consequence, the efficiency of reimbursement of medical devices by the national health insurance. These include providing manufacturers with the opportunity to better anticipate post-approval requirements, defining a study-specific primary objective, integrating a phase allowing dialogue between the manufacturer, the health authorities and the scientific committee, and increasing awareness and training of health professionals on the impact of post-approval clinical studies in terms of the reimbursement of medical devices by the national insurance.

Medical devices are many and various, ranging from tongue spatulas to implantable or invasive devices and imaging machines; their lifetimes are short, between 18 months and 5 years, due to incessant incremental innovation; and they are operator-dependent: in general, the clinical user performs a fitting procedure (hip implant or pacemaker), a therapeutic procedure using a non-implantable invasive device (arrhythmic site ablation probe, angioplasty balloon, extension spondyloplasty system, etc.) or follow-up of an active implanted device (long-term follow-up of an implanted cardiac defibrillator or of a deep brain stimulator in Parkinson's patients). A round-table held during the XXVIII(th) Giens Workshops meeting focused on the methodology of scientific evaluation of medical devices and the associated procedures with a view to their pricing and financing by the French National Health Insurance system. The working hypothesis was that the available data-set was sufficient for and compatible with scientific evaluation with clinical benefit. Post-registration studies, although contributing to the continuity of assessment, were not dealt with. Moreover, the focus was restricted to devices used in health establishments, where the association between devices and technical medical procedures is optimally representative. An update of the multiple regulatory protocols governing medical devices and procedures is provided. Issues more specifically related to procedures as such, to non-implantable devices and to innovative devices are then dealt with, and the proposals and discussion points raised at the round-table for each of these three areas are presented.

Background: Several countries have developed policy frameworks allowing timely access to promising health technologies on the condition that additional evidence is generated. However, an important barrier to evidence generation is the lack of structured collaboration among health technology assessment (HTA) agencies.Objectives: One of the aims of Work Package 7 (WP7) of the European network for Health Technology Assessment (EUnetHTA) Project was to determine the types of structured collaboration that could facilitate evidence generation and to develop a Web-based toolkit to support such collaboration.Methods: Collaboration modalities were defined by all WP7 Partners. Initial emphasis was on information sharing. Standardized forms for information sharing were developed and tested. An information technology development phase followed with the creation of the Web-based toolkit (Web site).Results: Three levels of collaboration were agreed on: (i) sharing information, (ii) coordinated action, and (iii) joint action. The Web site allows access to structured and standardized forms for requesting information, posting information in response to a request, and posting information spontaneously. An online database contains all of the information requested or posted. Pilot tests on twenty-one promising technologies were satisfactory.Conclusions: This new Web site for sharing information on evidence generation should help countries reach robust decisions on the timely adoption of promising health technologies. It will only become fully operational if EUnetHTA Partners supply relevant, accurate, and updated information, and regularly use the Web site.

Macrophages constitute major human immunodeficiency virus type 1 (HIV-1) reservoirs at the mucosal level, and their functional activity is modulated by cytokine environments that could play a role in HIV-1 mucosal spread. As proof of concept, we herein evaluated the modulation of HIV/macrophages interactions associated with two ubiquitous T h 2 cytokines, namely, interleukin (IL)–4 and IL-13, using the in vitro model of R5-HIV-1 transfer from macrophages to T lymphocytes. Monocyte-derived macrophages differentiated in the presence of IL-4 (M-4) transferred the virus to T cells more efficiently than those differentiated in the presence of interleukin-13 (M-13), likely because to their high capacity to capture and produce HIV-1 and to recruit HIV-1 target T cell. However, M-13 harbored high levels of HIV DNA, similarly to M-4, and secreted HIV-activating factors. Notably, uninfected macrophages recruited HIV-1 target T cells (CCR4 + IL-13 + T h 2 cells and CD4 + CCR5 + T cells), indicating their role in facilitating the HIV-1 spread by a passive manner. Strikingly, R5-HIV-1 reprogrammed macrophages toward a T h 1 secretion pattern. Thus, T h 2 microenvironment facilitates the emergence of HIV-1 macrophage reservoir and HIV-1 spread. In conclusion, secreted cytokines within mucosae may differentially influence both the HIV-1 production within the mucosal target cells reservoir and its spread thorough the mucosal tissue.

The increase of proinflammatory cytokines in vaginal secretions may serve as a surrogate marker of unwanted inflammatory reaction to microbicide products topically applied for the prevention of sexually transmitted diseases, including HIV-1. Interleukin (IL)-1 beta and 11,6 have been proposed as indicators of inflammation and increased risk of HIV-1 transmission; however, the lack of information regarding detection platforms optimal for vaginal fluids and interlaboratory variation limit their use for microbicide evaluation and other clinical applications. This study examines fluid matrix variants relevant to vaginal sampling techniques and proposes a model for interlaboratory comparisons across current cytokine detection technologies. IL-1 beta and IL-6 standards were measured by 12 laboratories in four countries, using 14 immunoassays and four detection platforms based on absorbance, chemiluminescence, electrochemiluminescence, and fluorescence. International reference preparations of cytokines with defined biological activity were spiked into (1) a defined medium simulating the composition of human vaginal fluid at pH 4.5 and 7.2, (2) physiologic salt solutions (phosphate-buffered saline and saline) commonly used for vaginal lavage sampling in clinical studies of cytokines, and (3) human blood serum. Assays were assessed for reproducibility, linearity, accuracy, and significantly detectable fold difference in cytokine level. Factors with significant impact on cytokine recovery were determined by Kruskal-Wallis analysis of variance with Dunn's multiple comparison test and multiple regression models. All assays showed acceptable intra-assay reproducibility; however, most were associated with significant interlaboratory variation. The smallest reliably detectable cytokine differences (P < 0.05) derived from pooled interlaboratory data varied from 1.5- to 26-fold depending on assay, cytokine, and matrix type. IL-6 but not IL-1 beta determinations were lower in both saline and phosphate-buffered saline as compared to vaginal fluid matrix, with no significant effect of pH. The (electro)chemiluminescence-based assays were most discriminative and consistently detected < 2-fold differences within each matrix type. The Luminex-based assays were less discriminative with lower reproducibility between laboratories. These results suggest the need for uniform vaginal sampling techniques and a better understanding of immunoassay platform differences and cross-validation before the biological significance of cytokine variations can be validated in clinical trials. This investigation provides the first standardized analytic approach for assessing differences in mucosal cytokine levels and may improve strategies for monitoring immune responses at the vaginal mucosal interface.

The differentiation and maturation of dendritic cells (DCs) is governed by various signals in the microenvironment. Monocytes and DCs circulate in peripheral blood, which contains high levels of natural antibodies (NAbs). NAbs are germ-line-encoded and occur in the absence of deliberate immunization or microbial aggression. To assess the importance of NAbs in the milieu on DC development, we examined the status of DCs in patients with X-linked agammaglobulinemia, a disease characterized by paucity of B cells and circulating antibodies. We demonstrate that the in vitro differentiation of DCs is severely impaired in these patients, at least in part because of low levels of circulating NAbs. We identified NAbs reactive with the CD40 molecule as an important component that participates in the development of DCs. CD40-reactive NAbs restored normal phenotypes of DCs in patients. The maturation process induced by CD40-reactive NAbs was accompanied by an increased IL-10 and decreased IL-12 production. The transcription factor analysis revealed distinct signaling pathways operated by CD40-reactive NAbs compared to those by CD40 ligand. These results suggest that B cells promote bystander DC development through NAbs and the interaction between NAbs and DCs may play a role in steady-state migration of DCs.

The present study demonstrates that CD4+CD25+ T cells, expanded in peripheral blood of HIV-infected patients receiving highly active antiretroviral therapy (HAART), exhibit phenotypic, molecular, and functional characteristics of regulatory T cells. The majority of peripheral CD4+CD25+ T cells from HIV-infected patients expressed a memory phenotype. They were found to constitutively express transcription factor forkhead box P3 (Foxp3) messengers. CD4+CD25+ T cells weakly proliferated to immobilized anti-CD3 monoclonal antibody (mAb) and addition of soluble anti-CD28 mAb significantly increased proliferation. In contrast to CD4+CD25– T cells, CD4+CD25+ T cells from HIV-infected patients did not proliferate in response to recall antigens and to p24 protein. The proliferative capacity of CD4 T cells to tuberculin, cytomegalovirus (CMV), and p24 significantly increased following depletion of CD4+CD25+ T cells. Furthermore, addition of increasing numbers of CD4+CD25+ T cells resulted in a dose-dependent inhibition of CD4+CD25– T-cell proliferation to tuberculin and p24. CD4+CD25+ T cells responded specifically to p24 antigen stimulation by expressing transforming growth factor β (TGF-β) and interleukin 10 (IL-10), thus indicating the presence of p24-specific CD4+ T cells among the CD4+CD25+ T-cell subset. Suppressive activity was not dependent on the secretion of TGF-β or IL-10. Taken together, our results suggest that persistence of HIV antigens might trigger the expansion of CD4+CD25+ regulatory T cells, which might induce a tolerance to HIV in vivo.

Dendritic cells (DCs) generated in the presence of IFN-alpha (IFN-DCs) exhibit high expression of major histocompatibility and co-stimulatory molecules and a potent ability to stimulate CD8(+) T-cell responses. Here, we found that IFN-DCs were more potent stimulators of bulk and purified CD8(+) T-cell proliferation, as compared with IL-4-DCs. In contrast, IFN-DCs were less efficient than IL-4-DCs in stimulating allogeneic CD4(+) T-cell proliferation, due to a weak induction of naive CD4(+)CD45RO(-) T-cell proliferation by these DCs. However, both DC populations induced similar levels of proliferation of memory CD4(+)CD45RO(+) T cells. IFN-DCs and IL-4-DCs exhibited a similar phenotype and production of IL-10 following maturation induced by CD40 ligation. In contrast, IFN-DCs produced higher levels of IL-10 during the first days of differentiation. In addition, neutralization of IL-10 during the differentiation of DCs increased the expression of DC-LAMP and MHC class II by IFN-DCs, and the ability of IFN-DCs to stimulate allogeneic CD4(+) T-cell proliferation at similar levels, than IL-4-DCs. Independently of IL-10 production, IFN-DCs were found to induce higher levels of CD4(+)T-cell apoptosis, this effect being more sticking on naive T cells. Finally, we demonstrated that IFN-DCs induced a differentiation bias of naive CD4(+) T cells towards Th1 and Tr1 cells, compared to IL-4-DCs. Taken together, these results indicate that, despite the induction of Tr1 cells and enhanced apoptosis of naive CD4(+) T cells, IFN-DCs are potent stimulators of CD8(+) and memory CD4(+) T cells, and induce a strong polarization of naive CD4(+) T cells towards Th1 cells, further supporting their use in immune-based therapy.

Objective To investigate the ability of granulocyte-macrophage colony-stimulating factor (GM-CSF) and IFN-alpha to induce the differentiation of peripheral monocytes into dendritic cells (DC) and their ability to trigger an HIV-specific CD8 T-cell response. Methods Monocytes isolated from both seronegative controls and HIV-infected individuals were differentiated into DC using GM-CSF with either IL-4 or IFN-alpha for 7 days. We assessed the phenotypic characteristics and IL-12 production by flow cytometry. The ability of DC to trigger CD8 T-cell responses was assessed by means of ELISpot and cytotoxicity assays. In addition, HIV-1-RNA levels were measured in culture supernatants. Results Compared with control DC generated in the presence of GM-CSF and IL-4, DC generated in the presence of GM-CSF and IFN-alpha expressed higher levels of MHC class I molecules and produced similar or higher levels of IL-12 after CD40 ligation or Staphyloccus aureus Cowan stimulation. GM-CSF/IFN-alpha DC expressed low levels of CD4, CXCR4 and DC-SIGN and did not produce detectable virus during the differentiation period. Pulsed GM-CSF/IFN-alpha DC were found to prime CD8 T cells from HIV-negative controls to exert cytotoxic activity against target cells expressing HIV antigens. HIV peptide-pulsed GM-CSF/IFN-alpha DC promote specific IFN-gamma production by autologous CD8 T cells from HIV-seronegative donors. Furthermore, GM-CSF/IFN-alpha DC from HIV-seropositive patients efficiently present HIV peptides to autologous CD8 T lymphocytes. Conclusion GM-CSF and IFN-alpha allow the generation of DC with high CD8 T-cell stimulating abilities. Therefore, this strategy may represent a novel approach to therapeutic vaccination in HIV disease.

Human lactoferrin (Lf) is an iron binding glycoprotein that is present in several mucosal secretions. Many biological functions have been ascribed to Lf. In the present study, we showed that Lf limited specifically adsorption of R5- and X4-HIV-1-free particles on endometrial epithelial HEC-1A cells, by inhibiting virus adsorption on heparan-sulfated proteoglycans. But, Lf did not interfere with both R5 and X4-HIV transcytosis. We showed also the efficacy of Lf in preventing R5 and X4-HIV capture by dendritic cells. Conversely, we demonstrated that Lf-reacting natural Abs (NAbs) present within i.v. Ig-enhanced HIV attachment on dendritic cells by forming HIV-Lf-NAbs. HIV particles were able to directly interact with Lf following its interaction with NAbs. We also found Lf-reacting natural Abs within cervicovaginal secretions, suggesting the existence of Lf-NAbs complexes in women genital tract in vivo. In conclusion, this study highlights Lf as a potent microbicides and reports new function for NAbs within the genital compartment that may compartment that may abolish the inhibitory activity of microbicide compounds. Thus, we proposed a model in which Lf would appear as a double-edged sword that could have beneficial or detrimental effects depending on both cellular and molecular environments. This study highlights the use of Lf derivates as microbicide candidates to limit such interferences.