Isolation and preliminary characterization of a human 'phage display'-derived antibody against neural adhesion molecule-1 antigen interfering with fibroblast growth factor receptor-1 binding.

BACKGROUND: The NCAM or CD56 antigen is a cell surface glycoprotein belonging to the immunoglobulin super-family involved in cell-cell and cell-matrix adhesion. NCAM is also over-expressed in many tumour types and is considered a tumour associated antigen, even if its role and biological mechanisms implicated in tumour progression and metastasis have not yet to be elucidated. In particular, it is quite well documented the role of the interaction between the NCAM protein and the fibroblast growth factor receptor-1 in metastasis and invasion, especially in the ovarian cancer progression. OBJECTIVE: Here we describe the isolation and preliminary characterization of a novel human anti-NCAM single chain Fragment variable antibody able to specifically bind NCAM-expressing cells, including epithelial ovarian cancer cells. METHODS: The antibody was isolate by phage display selection and was characterized by ELISA, FACS analysis and SPR experiments. Interference in EOC migration was analyzed by scratch test. RESULTS: It binds a partially linear epitope lying in the membrane proximal region of two fibronectin-like domains with a dissociation constant of 3.43 × 10-8 M. Interestingly, it was shown to interfere with the NCAM-FGFR1 binding and to partially decrease migration of EOC cells. CONCLUSIONS: According to our knowledge, this is the first completely human antibody able to interfere with this newly individuated cancer mechanism.

Optimization of hepatitis C virus screening strategies by birth cohort in Italy.

BACKGROUND AND AIMS: Cost-effective screening strategies are needed to make hepatitis C virus (HCV) elimination a reality. We determined if birth cohort screening is cost-effective in Italy. METHODS: A model was developed to quantify screening and healthcare costs associated with HCV. The model-estimated prevalence of undiagnosed HCV was used to calculate the antibody screens needed annually, with a €25 000 cost-effectiveness threshold. Outcomes were assessed under the status quo and a scenario that met the World Health Organization's targets for elimination of HCV. The elimination scenario was assessed under five screening strategies. RESULTS: A graduated birth cohort screening strategy (graduated screening 1: 1968-1987 birth cohorts, then expanding to 1948-1967 cohorts) was the least costly. This strategy would gain approximately 144 000 quality-adjusted life years (QALYs) by 2031 and result in an 89.3% reduction in HCV cases, compared to an 89.6%, 89.0%, 89.7% and 88.7% reduction for inversed graduated screening, 1948-77 birth cohort, 1958-77 birth cohort and universal screening, respectively. Graduated screening 1 yielded the lowest incremental cost-effectiveness ratio (ICER) of €3552 per QALY gained. CONCLUSIONS: In Italy, a graduated screening scenario is the most cost-effective strategy. Other countries could consider a similar birth cohort approach when developing HCV screening strategies.

Health and Climate Change: science calls for global action.

Climate changes affect social and environmental health determinants such as clean air, ecosystems health, safe drinking water and safe sufficient food. Globally, people at greatest risk of adverse health effects associated with climate change include children, the elderly and other vulnerable groups. Temperature-related death and illness, extreme events, polluted or stressed ecosystems represent relevant issues raising concern for both health and economic consequences. The aim of the Symposium "Health and Climate Change" (Istituto Superiore di Sanità, Rome 3-5 December 2018) was to promote an inter-sectoral and multidisciplinary approach to estimate and prevent climate change-related events as well as to call the authorities to put in place measures to reduce adverse health effects. At the end of the Symposium the Rome International Charter on Health and Climate Change was presented. It includes a series of actions and recommendations, discussed and shared by all the participants, intended to inform policy makers and all the stakeholders involved in the management of climate changes.

Development of a novel human phage display-derived anti-LAG3 scFv antibody targeting CD8+ T lymphocyte exhaustion.

BACKGROUND: Lymphocyte-activation gene (LAG)3 is a 498 aa transmembrane type I protein acting as an immune inhibitory receptor. It is expressed on activated lymphocytes, natural killer cells and plasmacytoid dendritic cells. In activated lymphocytes, LAG3 expression is involved in negative control of cell activation/proliferation to ensure modulation and control of immune responses. In view of its deregulated expression in tumor-infiltrating lymphocytes, LAG3, together with the additional immune checkpoint inhibitors CTLA4 and PD1, is considered a major target in order to reverse the immunosuppression typically mounting in oncologic diseases. Since many patients still fail to respond to current immune checkpoints-based therapies, the identification of new effective immune inhibitors is a priority in the ongoing fight against cancer. RESULTS: We identified a novel human single-chain variable fragment (scFv) Ab against a conformational epitope of LAG3 by in vitro phage display technology using the recombinant antigen as a bait. This scFv (referred to as F7) was characterized in terms of binding specificity to both recombinant antigen and human LAG3-expressing cells. It was then rebuilt into an IgG format pre-optimized for clinical usage, and the resulting bivalent construct was shown to preserve its ability to bind LAG3 on human cells. Next, we analyzed the activity of the anti-LAG3 scFvF7 using two different antigen-specific CD8+ T lymphocyte clones as target cells. We proved that the reconstituted anti-LAG3 F7 Ab efficiently binds the cell membrane of both cell clones after peptide-activation. Still more significantly, we observed a striking increase in the peptide-dependent cell activation upon Ab treatment as measured in terms of IFN-γ release by both ELISA and ELISPOT assays. CONCLUSIONS: Overall, the biotechnological strategy described herein represents a guiding development model for the search of novel useful immune checkpoint inhibitors. In addition, our functional data propose a novel candidate reagent for consideration as a cancer treatment.

Intracellular human antibody fragments recognizing the VP35 protein of Zaire Ebola filovirus inhibit the protein activity.

BACKGROUND: Ebola hemorrhagic fever is caused by the Ebola filovirus (EBOV), which is one of the most aggressive infectious agents known worldwide. The EBOV pathogenesis starts with uncontrolled viral replication and subversion of both the innate and adaptive host immune response. The multifunctional viral VP35 protein is involved in this process by exerting an antagonistic action against the early antiviral alpha/beta interferon (IFN-α/ß) response, and represents a suitable target for the development of strategies to control EBOV infection. Phage display technology permits to select antibodies as single chain Fragment variable (scFv) from an artificial immune system, due to their ability to specifically recognize the antigen of interest. ScFv is ideal for genetic manipulation and to obtain antibody constructs useful for targeting either antigens expressed on cell surface or intracellular antigens if the scFv is expressed as intracellular antibody (intrabody) or delivered into the cells. RESULTS: Monoclonal antibodies (mAb) in scFv format specific for the EBOV VP35 were isolated from the ETH-2 library of human recombinant antibodies by phage display technology. Five different clones were identified by sequencing, produced in E.coli and expressed in CHO mammalian cells to be characterized in vitro. All the selected scFvs were able to react with recombinant VP35 protein in ELISA, one of the scFvs being also able to react in Western Blot assay (WB). In addition, all scFvs were expressed in cell cytoplasm as intrabodies; a luciferase reporter gene inhibition assay performed in A549 cells showed that two of the scFvs can significantly hamper the inhibition of the IFN-ß-induced RIG-I signaling cascade mediated by EBOV VP35. CONCLUSION: Five antibodies in scFv format recognize an active form of EBOV VP35 in ELISA, while one antibody also recognizes VP35 in WB. Two of these scFvs were also able to interfere with the intracellular activity of VP35 in a cell system in vitro. These findings suggest that such antibodies in scFv format might be employed to develop therapeutic molecules able to hamper EBOV infections.

Multi-arm, multi-stage randomised controlled trials for evaluating therapeutic HIV cure interventions.

The evaluation of immune-based approaches to achieve an antiretroviral therapy free remission of HIV infection requires proven efficacy through antiretroviral therapy interruption placebo-controlled trials. This approach is not without risk to participants and innovative trial designs need to be developed that minimise the number of participants treated with placebo and ineffective candidates. Multi-arm, multi-stage (MAMS) trial designs can be used in this context to accelerate the development of an immune-based therapeutic agent for HIV cure. Issues related to implementing a MAMS design within the planned EHVA T01 trial are considered here. EHVA T01 is a multicentre, MAMS, double-blind, phase 1 and 2 trial that aims to evaluate the effect of immune interventions on viral control in HIV-1 infected participants following analytic treatment interruption. The application of a MAMS design increases the likelihood that the EHVA T01 trial will identify a successful treatment and minimises the number of participants undergoing analytical treatment interruptions who have been treated with futile agents. The use of a MAMS design is a promising strategy to evaluate complex immune-based approaches aimed at curing HIV-infection, particularly relevant to the pipeline with multiple agents requiring examination.

Economic Consequences of Investing in Anti-HCV Antiviral Treatment from the Italian NHS Perspective: A Real-World-Based Analysis of PITER Data.

OBJECTIVE: We estimated the cost consequence of Italian National Health System (NHS) investment in direct-acting antiviral (DAA) therapy according to hepatitis C virus (HCV) treatment access policies in Italy. METHODS: A multistate, 20-year time horizon Markov model of HCV liver disease progression was developed. Fibrosis stage, age and genotype distributions were derived from the Italian Platform for the Study of Viral Hepatitis Therapies (PITER) cohort. The treatment efficacy, disease progression probabilities and direct costs in each health state were obtained from the literature. The break-even point in time (BPT) was defined as the period of time required for the cumulative costs saved to recover the Italian NHS investment in DAA treatment. Three different PITER enrolment periods, which covered the full DAA access evolution in Italy, were considered. RESULTS: The disease stages of 2657 patients who consecutively underwent DAA therapy from January 2015 to December 2017 at 30 PITER clinical centres were standardized for 1000 patients. The investment in DAAs was considered to equal €25 million, €15 million, and €9 million in 2015, 2016, and 2017, respectively. For patients treated in 2015, the BPT was not achieved, because of the disease severity of the treated patients and high DAA prices. For 2016 and 2017, the estimated BPTs were 6.6 and 6.2 years, respectively. The total cost savings after 20 years were €50.13 and €55.50 million for 1000 patients treated in 2016 and 2017, respectively. CONCLUSIONS: This study may be a useful tool for public decision makers to understand how HCV clinical and epidemiological profiles influence the economic burden of HCV.

Patient-Reported Outcomes in First-Line Antiretroviral Therapy: Results From NEAT001/ANRS143 Trial Comparing Darunavir/Ritonavir in Combination With Tenofovir/Emtricitabine or Raltegravir.

BACKGROUND: There are few data comparing patient-reported outcomes (PROs) in randomized trials of initial antiretroviral therapy. We present results from a substudy of the NEAT001/ANRS143 trial. METHODS: The randomized trial compared first-line DRV/r 800/100 mg once daily plus RAL 400 mg twice daily and DRV/r plus TDF/FTC 245/200 mg once daily. Changes in PROs were assessed with 3 questionnaires: EuroQoL 5 domains (EQ-5D), Center for Epidemiologic Studies Depression (CES-D) scale, and HIV Treatment Satisfaction Questionnaire. Major depressive disorder (MDD) was defined as CES-D ≥ 16. General estimating equations were used to model change over 96 weeks in PROs from baseline. RESULTS: Of the 805 participants, 797 (99%) contributed to the substudy. Baseline PRO data were similar for the 2 randomized groups. Health status improved over time with a mean increase in EQ-5D visual analogue scale (VAS) of 8.0 by W96 [95% confidence interval (CI): 6.5 to 9.4; P < 0.001], and no statistically significant differences between groups (difference of 0.3 on VAS score (95% CI: -1.7 to 2.3); P = 0.7, global P value ≥0.05 for all domains over follow-up). There was no significant difference between groups on CES-D [difference of -0.1 (95% CI: -1.3 to 1.1); P = 0.9], or MDD during follow-up, adjusted for baseline MDD (odds ratio = 0.98, 95% CI: 0.82 to 1.18; P = 0.9). RAL + DRV/r group had lower level of convenience (P = 0.03) and fitted less well into patients' lifestyle (P = 0.007) than the TDF/FTC + DRV/r regimen, and was associated with lower treatment satisfaction [median score: 53 RAL + DRV/r vs 55 TDF/FTC + DRV/r (P = 0.001)]. CONCLUSION: PROs improved after starting antiretroviral therapy, with no statistically significant difference between groups. The lower satisfaction with RAL + DRV/r may be explained by twice-daily administration.

APOBEC3G/3A Expression in Human Immunodeficiency Virus Type 1-Infected Individuals Following Initiation of Antiretroviral Therapy Containing Cenicriviroc or Efavirenz.

Apolipoprotein B mRNA editing enzyme catalytic polypeptide-like 3 (APOBEC3) family members are cytidine deaminases that play crucial roles in innate responses to retrovirus infection. The mechanisms by which some of these enzymes restrict human immunodeficiency virus type 1 (HIV-1) replication have been extensively investigated in vitro. However, little is known regarding how APOBEC3 proteins affect the pathogenesis of HIV-1 infection in vivo and how antiretroviral therapy influences their expression. In this work, a longitudinal analysis was performed to evaluate APOBEC3G/3A expression in peripheral blood mononuclear cells of antiretroviral-naive HIV-1-infected individuals treated with cenicriviroc (CVC) or efavirenz (EFV) at baseline and 4, 12, 24, and 48 weeks post-treatment follow-up. While APOBEC3G expression was unaffected by therapy, APOBEC3A levels increased in CVC but not EFV arm at week 48 of treatment. APOBEC3G expression correlated directly with CD4+ cell count and CD4+/CD8+ cell ratio, whereas APOBEC3A levels inversely correlated with plasma soluble CD14. These findings suggest that higher APOBEC3G/3A levels may be associated with protective effects against HIV-1 disease progression and chronic inflammation and warrant further studies.

Economic Evaluation of the Hepatitis C Virus Treatment Extension to Early-Stage Fibrosis Patients: Evidence from the PITER Real-World Cohort.

OBJECTIVES: To conduct a cost-effectiveness analysis of two planning strategies of the second-generation direct-acting antiviral interferon-free regimens for the treatment of chronic hepatitis C virus infection. METHODS: A lifetime multicohort model comprised 8125 real-life patients enrolled in the PITER (Italian platform for the study of viral hepatitis) registry, implemented by the ISS (Istituto Superiore di Sanità). Two treatment planning strategies were compared: 1) policy 1-treat all patients regardless of the stage of fibrosis (F0-F4) with second-generation direct-acting antivirals and 2) policy 2-treat patients at F3/F4 stage and those who are prioritized by the scientific guidelines first, and the remaining patients when they reach the F3 stage. Clinical outcomes and costs were evaluated by using a lifetime horizon Markov model and adopting the third-party payer perspective. Health outcomes were expressed in terms of quality-adjusted life-years (QALYs). A sensitivity analysis was run to explore first- and second-order uncertainty and heterogeneity. An expected value of perfect information analysis was also conducted. RESULTS: Policy 1 exhibits an incremental cost-effectiveness ratio of €8,775/QALY gained and remains less than €30,000/QALY in 94% of realizations produced by the Monte-Carlo simulation. Such a proportion increases to 97% when adopting a threshold of €40,000/QALY gained. CONCLUSIONS: Moving from the urgency criterion to evidence-based escalating strategies when prioritizing the access to new anti-hepatitis C virus treatments is a good investment in health, whose affordability should be explored through context-specific budget impact analyses.

Forecasting Hepatitis C liver disease burden on real-life data. Does the hidden iceberg matter to reach the elimination goals?

BACKGROUND & AIMS: Advances in direct-acting antiviral treatment of HCV have reinvigorated public health initiatives aimed at identifying affected individuals. We evaluated the possible impact of only diagnosed and linked-to-care individuals on overall HCV burden estimates and identified a possible strategy to achieve the WHO targets by 2030. METHODS: Using a modelling approach grounded in Italian real-life data of diagnosed and treated patients, different linkage-to-care scenarios were built to evaluate potential strategies in achieving the HCV elimination goals. RESULTS: Under the 40% linked-to-care scenario, viraemic burden would decline (60%); however, eligible patients to treat will be depleted by 2025. Increased case finding through a targeted screening strategy in 1948-1978 birth cohorts could supplement the pool of diagnosed patients by finding 75% of F0-F3 cases. Under the 60% linked-to-care scenario, viraemic infections would decline by 70% by 2030 but the patients eligible for treatment will run out by 2028. If treatment is to be maintained, a screening strategy focusing on 1958-1978 birth cohorts could capture 55% of F0-F3 individuals. Under the 80% linked-to-care scenario, screening limited in 1968-1978 birth cohorts could sustain treatment at levels required to achieve the HCV elimination goals. CONCLUSION: In Italy, which is an HCV endemic country, the eligible pool of patients to treat will run out between 2025 and 2028. To maintain the treatment rate and achieve the HCV elimination goals, increased case finding in targeted, high prevalence groups is required.

Antibody response to hepatitis B vaccine in HIV-exposed infants in Malawi and correlation with HBV infection acquisition.

The aim of this study was to assess the immune response to HBV vaccine in HIV-exposed infants and to correlate it to HBV infection acquisition. Protective anti-HBs levels (>10 mIU/mL) were found in 54/58 (93.2%) infants at 6 months, 126/144 (87.5%) at 12 months and 141/176 (80.1%) children at 24 months. HBV infection (seven children were HBsAg + at Month 24) occurred also in the presence of levels above 10 mIU/mL. Our findings indicate limited impact of HIV exposure on anti-HBV immune response, but suggest that levels >10 mIU/mL may be required to confer protection in this context.

Soluble CD14 levels in plasma and breastmilk of Malawian HIV+ women: Lack of association with morbidity and mortality in their exposed infants.

PROBLEM: Data on soluble CD14 (sCD14) during pregnancy and lactation are scarce. We assessed the levels of sCD14 in plasma and breastmilk of Malawian HIV-positive women and evaluated the possible association with morbidity and mortality in the HIV-exposed children. METHOD OF STUDY: One hundred and forty-nine mother/child pairs were studied. Women received antiretroviral therapy from 26 weeks of gestation to at least 6 months of exclusive breastfeeding. sCD14 concentrations were determined using an enzyme-linked immunosorbent assay. RESULTS: sCD14 levels measured at 26 weeks of pregnancy (median: 1418 ng/mL, IQR: 1086-1757) were inversely correlated to maternal CD4+ cell count (r = -.283, P = .001) and to neonatal birthweight (r = -.233, P = .008). At 6 months, sCD14 plasma levels were significantly higher compared to baseline (1993 ng/mL, IQR: 1482-2604, P < .001), and breastmilk sCD14 levels (7668 ng/mL, IQR: 5495-10207) were 4-fold higher than in plasma (although the concentrations in the two compartments were not correlated). No association was found between sCD14 levels in plasma or breastmilk and morbidity or mortality in children. CONCLUSION: Higher sCD14 levels in HIV-positive women were associated with a more compromised maternal immunological status and to a lower neonatal birthweight, but not to poorer clinical outcomes in the HIV-exposed children.

Correction: Real-life data on potential drug-drug interactions in patients with chronic hepatitis C viral infection undergoing antiviral therapy with interferon-free DAAs in the PITER Cohort Study.

[This corrects the article DOI: 10.1371/journal.pone.0172159.].

The Manufacturers' Perspective on World Health Organization Prequalification of In Vitro Diagnostics.

In vitro diagnostic devices (IVDs) help clinicians determine specific conditions, monitor therapeutic efficacy, and prevent drug resistance development. While stringent regulatory authorities (SRAs) regulate IVDs in most high-income countries, regulatory authorities in many low- and middle-income countries (LMICs) are nonexistent or do not enforce rigorous standards. In 2010, the World Health Organization established its Prequalification of In Vitro Diagnostics (PQDx) program to ensure "access to safe, appropriate and affordable" IVDs, especially in LMICs with little or no domestic regulatory frameworks, thereby reaching underserved populations. However, challenges in PQDx policies and procedures include an overloaded pipeline, timelines not publicly available, confusion about which products PQDx focuses on, perceived burden for documenting changes to prequalified products, overlap with SRA approvals, and uncertainty around long-term financing. PQDx can maximize its impact by considering the perspective of IVD manufacturers; similarly, IVD manufacturers should exercise adequate quality control over their submissions and associated processes.

Predictors of attrition from care at 2 years in a prospective cohort of HIV-infected adults in Tigray, Ethiopia.

INTRODUCTION: Ethiopia has experienced rapid expansion of antiretroviral therapy (ART). However, as long-term retention in ART therapy is key for ART effectiveness, determinants of attrition need to be identified so appropriate interventions can be designed. METHODS: We used data from the 'Cohort of African people Starting Antiretroviral therapy' (CASA) project, a prospective study of a cohort of HIV-infected patients who started ART in seven health facilities (HFs). We analysed the data of patients who had started first-line ART between January 2013 and December 2014. The Kaplan-Meier method was used to estimate the probability of retention at different time points. The Cox proportional hazards model was used to identify factors associated with attrition. RESULTS: A total of 1198 patients were included in the study. Kaplan-Meier estimates of retention in care were 83.9%, 82.1% and 79.8% at 12, 18 and 24 months after starting ART, respectively. Attrition was mainly due to loss to follow-up, transferred-out patients and documented mortality. A multivariate Cox proportional hazard model showed that male sex, CD4 count <200 cells/µL and the type of HF were significantly associated with attrition. CONCLUSIONS: The observed attrition differences according to gender suggest that separate interventions designed for women and men should be explored. Moreover, innovative strategies to increase HIV testing should be supported to avoid CD4 levels falling too low, a factor significantly associated with higher attrition in our study. Finally, specific studies to analyse the reasons for different levels of attrition among HFs are required.