Biological and technical variables affecting immunoassay recovery of cytokines from human serum and simulated vaginal fluid: A multicenter study

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)-1β and IL-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-1β 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-1β 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

When does NICE recommend the use of health technologies within a programme of evidence development?

This article is made available through the Brunel Open Access Publishing Fund. This article is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and the source are credited.This article has been made available through the Brunel Open Access Publishing Fund.Background: There is growing interest internationally in linking reimbursement decisions with recommendations for further research. In the UK, the National Institute for Health and Clinical Excellence (NICE) can issue guidance to approve the routine use of a health intervention, reject routine use or recommend use within a research programme. These latter recommendations have restricted use to ‘only in research’ (OIR) or have recommended further research alongside routine use (‘approval with research’ or AWR). However, it is not currently clear when such recommendations are likely to be made. Objectives: This study aims to identify NICE technology appraisals where OIR or AWR recommendations were made and to examine the key considerations that led to those decisions. Methods: Draft and final guidance including OIR/AWR recommendations were identified. The documents were reviewed to establish the characteristics of the technology appraisal, the cost effectiveness of the technologies, the key considerations that led to the recommendations and the types of research required. Results: In total, 29 final and 31 draft guidance documents included OIR/AWR recommendations up to January 2010. Overall, 86 % of final guidance included OIR recommendations. Of these, the majority were for technologies considered to be cost ineffective (83 %) and the majority of final guidance (66 %) specified the need for further evidence on relative effectiveness. The use of OIR/AWR recommendations is decreasing over time and they have rarely been used in appraisals conducted through the single technology appraisal process. Conclusion: NICE has used its ability to recommend technologies within research programmes, although predominantly within the multiple technology appraisal process. OIR recommendations have been most frequently issued for technologies considered cost ineffective and the most frequently cited consideration is uncertainty related to relative effectiveness. Key considerations cited for most AWR recommendations and some OIR recommendations included a need for further evidence on long-term outcomes and adverse effects of treatment.Medical Research Counci

Immune reconstitution disease associated with parasitic infections following antiretroviral treatment

HIV-associated immune reconstitution disease (IRD) is the clinical presentation or deterioration of opportunistic infections that results from enhancement of pathogen-specific immune responses among patients responding to antiretroviral treatment (ART). The vast majority of reported cases of IRD have been associated with mycobacterial, chronic viral and invasive fungal infections; such cases result from dysregulated augmentation of cell-mediated type 1 cytokine-secreting host immune responses. However, the spectrum of infections now recognized as associated with IRD is expanding and includes a number of parasitic infections, which may be mediated by different immunopathological mechanisms. These include leishmaniasis (visceral, cutaneous, mucosal and post kala azar dermal leishmaniasis), schistosomiasis and strongyloidiasis. Since the major burden of HIV lies in resource-limited countries where access to ART is now rapidly expanding, increased awareness and knowledge of these phenomena is important. Here we review the clinical spectrum and pathogenesis of IRD associated with parasitic infections

Interferon-α Abrogates Tolerance Induction by Human Tolerogenic Dendritic Cells

BACKGROUND: Administration of interferon-α (IFN-α) represents an approved adjuvant therapy as reported for malignancies like melanoma and several viral infections. In malignant diseases, tolerance processes are critically involved in tumor progression. In this study, the effect of IFN-α on tolerance induction by human tolerogenic dendritic cells (DC) was analyzed. We focussed on tolerogenic IL-10-modulated DC (IL-10 DC) that are known to induce anergic regulatory T cells (iTregs). METHODOLOGY/PRINCIPAL FINDINGS: IFN-α promoted an enhanced maturation of IL-10 DC as demonstrated by upregulation of the differentiation marker CD83 as well as costimulatory molecules. IFN-α treatment resulted in an increased capacity of DC to stimulate T cell activation compared to control tolerogenic DC. We observed a strengthened T cell proliferation and increased IFN-γ production of CD4(+) and CD8(+) T cells stimulated by IFN-α-DC, demonstrating a restoration of the immunogenic capacity of tolerogenic DC in the presence of IFN-α. Notably, restimulation experiments revealed that IFN-α treatment of tolerogenic DC abolished the induction of T cell anergy and suppressor function of iTregs. In contrast, IFN-α neither affected the priming of iTregs nor converted iTregs into effector T cells. CONCLUSIONS/SIGNIFICANCE: IFN-α inhibits the induction of T cell tolerance by reversing the tolerogenic function of human DC

Relationship between Regulatory T Cells and Immune Activation in Human Immunodeficiency Virus-Infected Patients Interrupting Antiretroviral Therapy

Persistent immune activation plays a central role in driving Human Immunodeficiency Virus (HIV) disease progression. Whether CD4+CD25+ regulatory T cells (Tregs) are harmful by suppressing HIV-specific immune responses and/or beneficial through a decrease in immune activation remains debatable. We analysed the relationship between proportion and number of regulatory T cells (Tregs) and immune activation in HIV-infected patients interrupting an effective antiretroviral therapy (ART). Twenty-five patients were included in a substudy of a prospective multicenter trial of treatment interruption (TI) (ANRS 116). Proportions and numbers of Tregs and the proportion of activated CD4 and CD8 T cells were assessed at baseline and month 12 (M12) of TI. Specific anti-HIV CD4 and CD8 responses were investigated at baseline and M12. Non parametric univariate analyses and multivariate linear regression models were conducted. At baseline, the proportion of Tregs negatively correlated with the proportion of HLA-DR+CD8+T cells (r = −0.519). Following TI, the proportion of Tregs increased from 6.3% to 7.2% (p = 0.029); absolute numbers of Tregs decreased. The increase in the proportion of HLA-DR+CD38+CD8+T cells was significantly related to the increase in proportion of Tregs (p = 0.031). At M12, the proportion of Tregs did not negatively correlate with CD8 T-cell activation. Nevertheless, Tregs retain a suppressive function since depletion of Treg-containing CD4+CD25+ cells led to an increase in lymphoproliferative responses in most patients studied. Our data suggest that Tregs are efficient in controlling residual immune activation in patients with ART-mediated viral suppression. However, the insufficient increase in the proportion and/or the decrease in the absolute number of Tregs result in a failure to control immune activation following TI

Immunosuppression during Acute Infection with Foot-and-Mouth Disease Virus in Swine Is Mediated by IL-10

Foot-and-mouth disease virus (FMDV) is one of the most contagious animal viruses, causing a devastating disease in cloven-hoofed animals with enormous economic consequences. Identification of the different parameters involved in the immune response elicited against FMDV remains unclear, and it is fundamental the understanding of such parameters before effective control measures can be put in place. In the present study, we show that interleukin-10 (IL-10) production by dendritic cells (DCs) is drastically increased during acute infection with FMDV in swine. In vitro blockade of IL-10 with a neutralizing antibody against porcine IL-10 restores T cell activation by DCs. Additionally, we describe that FMDV infects DC precursors and interferes with DC maturation and antigen presentation capacity. Thus, we propose a new mechanism of virus immunity in which a non-persistent virus, FMDV, induces immunosuppression by an increment in the production of IL-10, which in turn, reduces T cell function. This reduction of T cell activity may result in a more potent induction of neutralizing antibody responses, clearing the viral infection

Caractérisation phénotypique et fonctionnelle de cellules dendritiques différenciées en présence de GM-CSF et d'Interféron-a, dérivées de monocytes issus de donneurs sains ou infectés par le VIH

Au cours de ces études, nous avons montré la capacité de l'association GM-CSF/IFN-a à différencier des CD à partir de monocytes isolés de donneurs sains (ou CD/IFN). Les CD/IFN stimulent plus efficacement les lymphocytes T CD8+, aussi bien les cellules TCD4+ mémoires mais plus faiblement lymphocytes T CD4+ naifs que les CD/IF-4. Les CD/IFN induisent plus efficacement la génération des cellules Th1 et Tr1. Lorsque les monocytes sont isolés de patients infectés par le VIH, les CD/IFN et CD/IL-4 stimulent de la même manière les lymphocytes T CD8+ mais plus faiblement les lymphocytes T CD4+. En présence d'anticorps anti-IL-10, la prolifération de lymphocytes T CD4+...PARIS5-BU-Necker : Fermée (751152101) / SudocPARIS-BIUP (751062107) / SudocSudocFranceF

The French reporting system for drug shortages: description and trends from 2012 to 2018: an observational retrospective study

International audienceObjectives The aim was to provide figures for drug shortages in France and describe their characteristics, causes and trends between 2012 and 2018. Methods Data from the national reporting system from the Agency of Medicine and Health Product Safety (ANSM) was analysed. This database contains information regarding effective and predicted shortages of major therapeutic of interest drugs (ie, drugs whose shortage would be life-threatening or representing a loss of treatment opportunity for patients with a severe disease) which are mandatory reported by marketing authorisation holders to the ANSM. Data are presented as numbers or percentages of pharmaceutical products (ie, the product name and its formulation) reported on shortage between 2012 and 2018. Results There were 3530 pharmaceutical products reported on shortage during the period, including 1833 different active substances. Drugs on shortage were mostly old products (63.4%) with national marketing authorisation procedures (62.8%), as well as injectable and oral forms (47.5% and 43.3%, respectively). Anti-infectives for systemic use ranked first (18%), followed by nervous and cardiovascular system drugs and by antineoplastic and immunomodulating agents (17.4%, 12.5% and 10.4%, respectively). The number of reported shortages presented a fourfold increase between 2012 and 2018 and a sharp rise in 2017 and 2018, along with a rise in the number of active substances on shortage. The therapeutic classes concerned remained similar over time. Manufacturing and material supply issues were the main reported reasons for the shortage each year (30%) and there was an overall rise of pharmaceutical market reasons. Conclusion Drug shortages were increasingly reported in France. Preventive measures should specifically target the products most on shortage, in particular old drugs, injectable, anti-infective, nervous system and cardiovascular system drugs as well as antineoplastic and immunomodulating agents