199 results on '"Clementi, N."'
Search Results
102. [Structured implementation and high adherence to the ERAS program in colorectal surgery in two operating units of the ASUR Marche.]
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Catarci M, Maurizi A, Benedetti M, Giachetta A, Ciotti S, Spinelli F, Bernacconi T, Gionni B, Astolfi L, Paoletti C, Forlini G, Marzocchini S, Casuale G, Valeri MV, Clementi N, Cicconi S, Marziali I, Guercioni G, and Campagnacci R
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- Humans, Length of Stay, Postoperative Complications epidemiology, Postoperative Complications prevention & control, Colorectal Surgery, Enhanced Recovery After Surgery
- Abstract
Background: An Enhanced Recovery After Surgery (ERAS) program in colorectal surgery is able to significantly reduce the morbidity rates and postoperative hospital stay (LOS) related to the intervention. However, it is not clear what modalities and levels of implementation are necessary to achieve these results. The purpose of this work is to analyze the methods and results of the first year of implementation of the program in two centers of the Agenzia Sanitaria Unica Regionale (ASUR) Marche., Materials: After a structured implementation pathway, characterized by the creation of a core team, field training, internal courses and coaching, the details of 196 consecutive cases of patients submitted to colorectal resection over a one-year period in two surgical units of the ASUR Marche were prospectively loaded in a database, considering over 50 variables including adherence to the individual items of the ERAS program. The primary outcomes were: overall and major morbidity, mortality and anastomotic dehiscence rates; secondary outcomes were: LOS, re-admission and re-intervention rates. The results of primary endpoints were evaluated by univariable and multivariable analyses with logistic regression and, thereafter, according to ERAS item adherence rate., Results: After a median (interquartile range, IQR) follow-up of 40 (32-94) days, we recorded complications in 72 patients (overall morbidity 36.7%), major morbidity in 14 patients (7.1%), 6 deaths (mortality 3.1%), an anastomotic dehiscence in 9 cases (4.9%), median (IQR) overalll LOS 5 (3-7) days, 10 readmissions (5.1%) and 13 reoperations (6.7%). The mean adherence rate to the items of the ERAS program was 85.4%, showing a significant dose-effect curve for overall morbidity, major morbidity, anastomotic leakage and for overall LOS., Discussion: The ERAS implementation methods in this project led to a high adherence (>80%) to the program items. All the results showed a significant improvement compared to the previous pre-implementation period and according to the adherence to program items rate.
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- 2021
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103. A spatial multi-scale fluorescence microscopy toolbox discloses entry checkpoints of SARS-CoV-2 variants in Vero E6 cells.
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Storti B, Quaranta P, Di Primio C, Clementi N, Mancini N, Criscuolo E, Spezia PG, Carnicelli V, Lottini G, Paolini E, Freer G, Lai M, Costa M, Beltram F, Diaspro A, Pistello M, Zucchi R, Bianchini P, Signore G, and Bizzarri R
- Abstract
We exploited a multi-scale microscopy imaging toolbox to address some major issues related to SARS-CoV-2 interactions with host cells. Our approach harnesses both conventional and super-resolution fluorescence microscopy and easily matches the spatial scale of single-virus/cell checkpoints. After its validation through the characterization of infected cells and virus morphology, we leveraged this toolbox to reveal subtle issues related to the entry phase of SARS-CoV-2 variants in Vero E6 cells. Our results show that in Vero E6 cells the B.1.1.7 strain (aka Alpha Variant of Concern) is associated with much faster kinetics of endocytic uptake compared to its ancestor B.1.177. Given the cell-entry scenario dominated by the endosomal "late pathway", the faster internalization of B.1.1.7 could be directly related to the N501Y mutation in the S protein, which is known to strengthen the binding of Spike receptor binding domain with ACE2. Remarkably, we also directly observed the central role of clathrin as a mediator of endocytosis in the late pathway of entry. In keeping with the clathrin-mediated endocytosis, we highlighted the non-raft membrane localization of ACE2. Overall, we believe that our fluorescence microscopy-based approach represents a fertile strategy to investigate the molecular features of SARS-CoV-2 interactions with cells., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2021 The Authors.)
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- 2021
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104. Naringenin is a powerful inhibitor of SARS-CoV-2 infection in vitro.
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Clementi N, Scagnolari C, D'Amore A, Palombi F, Criscuolo E, Frasca F, Pierangeli A, Mancini N, Antonelli G, Clementi M, Carpaneto A, and Filippini A
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- Humans, SARS-CoV-2, COVID-19, Flavanones pharmacology, Pharmaceutical Preparations
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- 2021
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105. Global and local envelope protein dynamics of hepatitis C virus determine broad antibody sensitivity.
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Augestad EH, Castelli M, Clementi N, Ströh LJ, Krey T, Burioni R, Mancini N, Bukh J, and Prentoe J
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- Antibodies, Neutralizing, Hepatitis C Antibodies, Humans, Viral Envelope Proteins metabolism, Hepacivirus genetics, Hepatitis C
- Abstract
Broad antibody sensitivity differences of hepatitis C virus (HCV) isolates and their ability to persist in the presence of neutralizing antibodies (NAbs) remain poorly understood. Here, we show that polymorphisms within glycoprotein E2, including hypervariable region 1 (HVR1) and antigenic site 412 (AS412), broadly affect NAb sensitivity by shifting global envelope protein conformation dynamics between theoretical "closed," neutralization-resistant and "open," neutralization-sensitive states. The conformational space of AS412 was skewed toward β-hairpin-like conformations in closed states, which also depended on HVR1, assigning function to these enigmatic E2 regions. Scavenger receptor class B, type I entry dependency of HCV was associated with NAb resistance and correlated perfectly with decreased virus propensity to interact with HCV co-receptor CD81, indicating that decreased NAb sensitivity resulted in a more complex entry pathway. This link between global E1/E2 states and functionally distinct AS412 conformations has important implications for targeting AS412 in rational HCV vaccine designs., (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).)
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- 2020
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106. Type III interferons disrupt the lung epithelial barrier upon viral recognition.
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Broggi A, Ghosh S, Sposito B, Spreafico R, Balzarini F, Lo Cascio A, Clementi N, De Santis M, Mancini N, Granucci F, and Zanoni I
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- Animals, Bronchoalveolar Lavage Fluid immunology, COVID-19, Cell Proliferation, Cytokines metabolism, Humans, Interferon Type I metabolism, Interferons metabolism, Lung immunology, Mice, Mice, Inbred C57BL, Nasopharynx immunology, Pandemics, Poly I-C administration & dosage, Respiratory Mucosa pathology, SARS-CoV-2, Signal Transduction, Staphylococcal Infections metabolism, Superinfection, Toll-Like Receptor 3 metabolism, Interferon Lambda, Betacoronavirus, Coronavirus Infections immunology, Coronavirus Infections metabolism, Dendritic Cells metabolism, Interferons physiology, Lung metabolism, Lung pathology, Pneumonia, Viral immunology, Pneumonia, Viral metabolism
- Abstract
Viral infections of the lower respiratory tract are a leading cause of mortality. Mounting evidence indicates that most severe cases are characterized by aberrant immune responses and do not depend on viral burden. In this study, we assessed how type III interferons (IFN-λ) contribute to the pathogenesis induced by RNA viruses. We report that IFN-λ is present in the lower, but not upper, airways of patients with coronavirus disease 2019 (COVID-19). In mice, we demonstrate that IFN-λ produced by lung dendritic cells in response to a synthetic viral RNA induces barrier damage, causing susceptibility to lethal bacterial superinfections. These findings provide a strong rationale for rethinking the pathophysiological role of IFN-λ and its possible use in clinical practice against endemic viruses, such as influenza virus as well as the emerging severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection., (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)
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- 2020
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107. Interferon-β-1a Inhibition of Severe Acute Respiratory Syndrome-Coronavirus 2 In Vitro When Administered After Virus Infection.
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Clementi N, Ferrarese R, Criscuolo E, Diotti RA, Castelli M, Scagnolari C, Burioni R, Antonelli G, Clementi M, and Mancini N
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- Animals, Betacoronavirus physiology, COVID-19, Chlorocebus aethiops, Drug Repositioning, Pandemics, SARS-CoV-2, Vero Cells, Virus Replication drug effects, Antiviral Agents pharmacology, Betacoronavirus drug effects, Coronavirus Infections drug therapy, Coronavirus Infections virology, Interferon beta-1a pharmacology, Pneumonia, Viral drug therapy, Pneumonia, Viral virology
- Abstract
The ongoing coronavirus disease 2019 pandemic has forced the clinical and scientific community to try drug repurposing of existing antiviral agents as a quick option against severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2). Under this scenario, interferon (IFN) β-1a, whose antiviral potential is already known, and which is a drug currently used in the clinical management of multiple sclerosis, may represent as a potential candidate. In this report, we demonstrate that IFN-β-1a was highly effective in inhibiting in vitro SARS-CoV-2 replication at clinically achievable concentration when administered after virus infection., (© The Author(s) 2020. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)
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- 2020
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108. Molecular Tracing of SARS-CoV-2 in Italy in the First Three Months of the Epidemic.
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Lai A, Bergna A, Caucci S, Clementi N, Vicenti I, Dragoni F, Cattelan AM, Menzo S, Pan A, Callegaro A, Tagliabracci A, Caruso A, Caccuri F, Ronchiadin S, Balotta C, Zazzi M, Vaccher E, Clementi M, Galli M, and Zehender G
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- Bayes Theorem, Betacoronavirus isolation & purification, COVID-19, Epidemiological Monitoring, Genome, Viral, Humans, Italy epidemiology, Likelihood Functions, Molecular Epidemiology, Molecular Typing, Mutation, Phylogeny, SARS-CoV-2, Time Factors, Whole Genome Sequencing, Betacoronavirus classification, Betacoronavirus genetics, Coronavirus Infections epidemiology, Coronavirus Infections virology, Pandemics, Pneumonia, Viral epidemiology, Pneumonia, Viral virology
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The aim of this study is the characterization and genomic tracing by phylogenetic analyses of 59 new SARS-CoV-2 Italian isolates obtained from patients attending clinical centres in North and Central Italy until the end of April 2020. All but one of the newly-characterized genomes belonged to the lineage B.1, the most frequently identified in European countries, including Italy. Only a single sequence was found to belong to lineage B. A mean of 6 nucleotide substitutions per viral genome was observed, without significant differences between synonymous and non-synonymous mutations, indicating genetic drift as a major source for virus evolution. tMRCA estimation confirmed the probable origin of the epidemic between the end of January and the beginning of February with a rapid increase in the number of infections between the end of February and mid-March. Since early February, an effective reproduction number (R
e ) greater than 1 was estimated, which then increased reaching the peak of 2.3 in early March, confirming the circulation of the virus before the first COVID-19 cases were documented. Continuous use of state-of-the-art methods for molecular surveillance is warranted to trace virus circulation and evolution and inform effective prevention and containment of future SARS-CoV-2 outbreaks.- Published
- 2020
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109. Detection of low-level HCV variants in DAA treated patients: comparison amongst three different NGS data analysis protocols.
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Caputo V, Diotti RA, Boeri E, Hasson H, Sampaolo M, Criscuolo E, Bagaglio S, Messina E, Uberti-Foppa C, Castelli M, Burioni R, Mancini N, Clementi M, and Clementi N
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- Aged, Amino Acid Substitution, Coinfection virology, Computer Simulation, Data Analysis, Genotype, Hepatitis C, Chronic blood, Hepatitis C, Chronic virology, High-Throughput Nucleotide Sequencing, Humans, Male, Middle Aged, Software, Treatment Failure, Viral Nonstructural Proteins classification, Antiviral Agents therapeutic use, Genetic Variation, Hepacivirus genetics, Hepatitis C, Chronic drug therapy, Viral Nonstructural Proteins genetics
- Abstract
Background: Notwithstanding the efforts of direct-acting antivirals (DAAs) for the treatment of chronically infected hepatitis C virus (HCV) patients, concerns exist regarding the emergence of resistance-associated substitutions (RAS) related to therapy failure. Sanger sequencing is still the reference technique used for the detection of RAS and it detects viral variants present up to 15%, meaning that minority variants are undetectable, using this technique. To date, many studies are focused on the analysis of the impact of HCV low variants using next-generation sequencing (NGS) techniques, but the importance of these minority variants is still debated, and importantly, a common data analysis method is still not defined., Methods: Serum samples from four patients failing DAAs therapy were collected at baseline and failure, and amplification of NS3, NS5A and NS5B genes was performed on each sample. The genes amplified were sequenced using Sanger and NGS Illumina sequencing and the data generated were analyzed with different approaches. Three different NGS data analysis methods, two homemade in silico pipeline and one commercially available certified user-friendly software, were used to detect low-level variants., Results: The NGS approach allowed to infer also very-low level virus variants. Moreover, data processing allowed to generate high accuracy data which results in reduction in the error rates for each single sequence polymorphism. The results improved the detection of low-level viral variants in the HCV quasispecies of the analyzed patients, and in one patient a low-level RAS related to treatment failure was identified. Importantly, the results obtained from only two out of the three data analysis strategies were in complete agreement in terms of both detection and frequency of RAS., Conclusions: These results highlight the need to find a robust NGS data analysis method to standardize NGS results for a better comprehension of the clinical role of low-level HCV variants. Based on the extreme importance of data analysis approaches for wet-data interpretation, a detailed description of the used pipelines and further standardization of the in silico analysis could allow increasing diagnostic laboratory networking to unleash true potentials of NGS.
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- 2020
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110. Combined Prophylactic and Therapeutic Use Maximizes Hydroxychloroquine Anti-SARS-CoV-2 Effects in vitro .
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Clementi N, Criscuolo E, Diotti RA, Ferrarese R, Castelli M, Dagna L, Burioni R, Clementi M, and Mancini N
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While the SARS-CoV-2 pandemic is heavily hitting the world, it is of extreme importance that significant in vitro observations guide the quick set up of clinical trials. In this study, we evidence that the anti-SARS-CoV2 activity of a clinically achievable hydroxychloroquine concentration is maximized only when administered before and after the infection of Vero E6 and Caco-2 cells. This suggests that only a combined prophylactic and therapeutic use of hydroxychloroquine may be effective in limiting viral replication in patients., (Copyright © 2020 Clementi, Criscuolo, Diotti, Ferrarese, Castelli, Dagna, Burioni, Clementi and Mancini.)
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- 2020
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111. Lower nasopharyngeal viral load during the latest phase of COVID-19 pandemic in a Northern Italy University Hospital.
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Clementi N, Ferrarese R, Tonelli M, Amato V, Racca S, Locatelli M, Lippi G, Silvestri G, Clementi M, and Mancini N
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- Adolescent, Adult, Age Factors, Aged, Aged, 80 and over, COVID-19, COVID-19 Testing, Child, Clinical Laboratory Techniques, Coronavirus Infections diagnosis, Female, Hospitals, University, Humans, Italy, Male, Middle Aged, Pandemics, Pilot Projects, Pneumonia, Viral diagnosis, Reverse Transcriptase Polymerase Chain Reaction, SARS-CoV-2, Young Adult, Betacoronavirus, Coronavirus Infections virology, Nasopharynx virology, Pneumonia, Viral virology, Viral Load
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Objectives: A milder clinical course of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has been anecdotally reported over the latest phase of COVID-19 pandemic in Italy. Several factors may contribute to this observation, including the effect of lockdown, social distancing, lower humidity, lower air pollution, and potential changes in the intrinsic pathogenicity of the virus. In this regard, the clinical severity of COVID-19 could be attenuated by mutations in SARS-CoV-2 genome that decrease its virulence, as well as by lower virus inocula., Methods: In this pilot study, we compared the reverse transcription polymerase chain reaction (RT-PCR) amplification profile of 100 nasopharyngeal swabs consecutively collected in April, during the peak of SARS-CoV-2 epidemic, to that of 100 swabs collected using the same procedure in May., Results: The mean Ct value of positive samples collected in May was significantly higher than that of samples collected in the previous period (ORF 1a/b gene: 31.85 ± 0.32 vs. 28.37 ± 0.5, p<0.001; E gene: 33.76 ± 0.38 vs. 29.79 ± 0.63, p<0.001), suggesting a lower viral load at the time of sampling. No significant differences were observed between male and females in the two periods, whilst higher viral loads were found in (i) patients over 60-years old, and (ii) patients that experienced severe COVID-19 during the early stages of the pandemic., Conclusions: This pilot study prompts further investigation on the correlation between SARS-CoV-2 load and different clinical manifestation of COVID-19 during different phases of the pandemic. Laboratories should consider reporting quantitative viral load data in the molecular diagnosis of SARS-CoV-2 infection.
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- 2020
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112. Differential Composition of Vaginal Microbiome, but Not of Seminal Microbiome, Is Associated With Successful Intrauterine Insemination in Couples With Idiopathic Infertility: A Prospective Observational Study.
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Amato V, Papaleo E, Pasciuta R, Viganò P, Ferrarese R, Clementi N, Sanchez AM, Quaranta L, Burioni R, Ambrosi A, Salonia A, Clementi M, Candiani M, and Mancini N
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Background: Vaginal and seminal microbiomes have gained increasing interest for their involvement in reproductive health and fertility. However, their role in reproductive outcome is not fully understood yet. In this study, we aimed to correlate the vaginal and the seminal microbiome of 23 couples with idiopathic infertility to the clinical pregnancy rate after intrauterine insemination (IUI)., Methods: Vaginal swabs and seminal fluids were collected on the day of IUI procedure and analyzed through polymerase chain reaction amplification of variable regions 3 and 4 (V3-V4) of 16S ribosomal ribonucleic acid genes and Illumina MiSeq sequencing. The taxonomic data were then correlated to IUI success., Results: Idiopathic infertile women showed a different average composition of vaginal microbiome compared with control sequences, whereas for seminal counterpart no relevant differences were observed. Furthermore, among idiopathic infertile women, different patterns of Lactobacillus species dominations were observed, with a predominance either of Lactobacillus crispatus , a marker of a healthy vaginal ecosystem, or of Lactobacillus iners and Lactobacillus gasseri , associated with a more dysbiosis-prone environment. More important, considering all investigated variables, vaginal L crispatus domination was the only factor strongly associated to IUI success ( P = .0002)., Conclusions: Our results strengthen the potential role of L crispatus in promoting a favorable environment for pregnancy and suggest that microbiome characterization could be useful, together with standard clinical and laboratory assessments, in the pre-IUI evaluation of infertile couples., (© The Author(s) 2019. Published by Oxford University Press on behalf of Infectious Diseases Society of America.)
- Published
- 2019
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113. Cell-to-Cell Spread Blocking Activity Is Extremely Limited in the Sera of Herpes Simplex Virus 1 (HSV-1)- and HSV-2-Infected Subjects.
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Criscuolo E, Castelli M, Diotti RA, Amato V, Burioni R, Clementi M, Ambrosi A, Mancini N, and Clementi N
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- Adult, Animals, Chlorocebus aethiops, Female, HEK293 Cells, Herpes Simplex virology, Herpesvirus 1, Human immunology, Herpesvirus 1, Human metabolism, Herpesvirus 2, Human immunology, Herpesvirus 2, Human metabolism, Humans, Immunity, Humoral immunology, Male, Neutralization Tests, Vero Cells, Viral Envelope Proteins blood, Viral Envelope Proteins immunology, Virion metabolism, Virus Internalization, Antibodies, Neutralizing immunology, Antibodies, Viral immunology, Virus Replication immunology
- Abstract
Herpes simplex virus 1 (HSV-1) and HSV-2 can evade serum antibody-mediated neutralization through cell-to-cell transmission mechanisms, which represent one of the central steps in disease reactivation. To address the role of humoral immunity in controlling HSV-1 and HSV-2 replication, we analyzed serum samples from 44 HSV-1 and HSV-2 seropositive subjects by evaluating (i) their efficiency in binding both the purified viral particles and recombinant gD and gB viral glycoproteins, (ii) their neutralizing activity, and (iii) their capacity to inhibit the cell-to-cell virus passage in vitro All of the sera were capable of binding gD, gB, and whole virions, and all sera significantly neutralized cell-free virus. However, neither whole sera nor purified serum IgG fraction was able to inhibit significantly cell-to-cell virus spreading in in vitro post-virus-entry infectious assays. Conversely, when spiked with an already described anti-gD human monoclonal neutralizing antibody capable of inhibiting HSV-1 and -2 cell-to-cell transmission, each serum boosted both its neutralizing and post-virus-entry inhibitory activity, with no interference exerted by serum antibody subpopulations. IMPORTANCE Despite its importance in the physiopathology of HSV-1 and -2 infections, the cell-to-cell spreading mechanism is still poorly understood. The data shown here suggest that infection-elicited neutralizing antibodies capable of inhibiting cell-to-cell virus spread can be underrepresented in most infected subjects. These observations can be of great help in better understanding the role of humoral immunity in controlling virus reactivation and in the perspective of developing novel therapeutic strategies, studying novel correlates of protection, and designing effective vaccines., (Copyright © 2019 American Society for Microbiology.)
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- 2019
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114. Answer to February 2019 Photo Quiz.
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Tavano C, Pasciuta R, Carletti S, Ossi CM, Ieri R, Cichero P, Clementi N, Burioni R, Clementi M, and Mancini N
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- 2019
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115. Photo Quiz: Neurological Symptoms in a 74-Year-Old Diabetic Woman Admitted to the Emergency Room.
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Tavano C, Pasciuta R, Carletti S, Ossi CM, Ieri R, Cichero P, Clementi N, Burioni R, Clementi M, and Mancini N
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- 2019
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116. Synergy evaluation of anti-Herpes Simplex Virus type 1 and 2 compounds acting on different steps of virus life cycle.
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Criscuolo E, Clementi N, Mancini N, Burioni R, Miduri M, Castelli M, and Clementi M
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- Animals, Antibodies, Viral pharmacology, Chlorocebus aethiops, Drug Synergism, Herpesvirus 1, Human immunology, Herpesvirus 1, Human physiology, Herpesvirus 2, Human, Inhibitory Concentration 50, Vero Cells, Virus Internalization drug effects, Virus Replication drug effects, Antibodies, Monoclonal pharmacology, Antibodies, Neutralizing pharmacology, Antiviral Agents pharmacology, Herpes Simplex virology, Herpesvirus 1, Human drug effects
- Abstract
Despite the clinical need of novel and safe anti-herpetic compounds effective for treating both primary infections and reactivations of Herpes Simplex Virus type 1 (HSV-1) and type 2 (HSV-2), the development of novel antivirals approved for clinical administration has been limited in the last decades to improvements of nucleoside analogues compounds. In this context, targeting different steps of the herpesvirus life cycle, including entry and cell-to-cell infection, can represent an important starting point for obtaining more efficient infection inhibition, and for overcoming both drug resistance and toxicity. Under these perspectives, testing possible synergy between drugs currently in clinical use and novel immunotherapeutics, such as neutralizing human monoclonal antibodies, represents a fascinating option. In the study here described we tested for the first-time possible combinations of inhibitors of Herpesvirus DNA synthesis and a human neutralizing IgG able to block also cell-to-cell infection, by analysing experimental results with different mathematical models. The present study clearly highlights the synergism between all anti-herpetic drugs tested in combination with the mAb; this strongly suggests possible reduction of anti-herpetic drugs combined with the IgG for overcoming drug-related side effects, as indicated by Drug Reduction Index., (Copyright © 2018 Elsevier B.V. All rights reserved.)
- Published
- 2018
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117. Atomic mutagenesis of stop codon nucleotides reveals the chemical prerequisites for release factor-mediated peptide release.
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Hoernes TP, Clementi N, Juen MA, Shi X, Faserl K, Willi J, Gasser C, Kreutz C, Joseph S, Lindner H, Hüttenhofer A, and Erlacher MD
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- Escherichia coli Proteins metabolism, Mutagenesis, Site-Directed, Nucleotides, Peptide Chain Termination, Translational, Protein Biosynthesis, Codon, Terminator genetics, Escherichia coli metabolism, Peptide Termination Factors physiology
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Termination of protein synthesis is triggered by the recognition of a stop codon at the ribosomal A site and is mediated by class I release factors (RFs). Whereas in bacteria, RF1 and RF2 promote termination at UAA/UAG and UAA/UGA stop codons, respectively, eukaryotes only depend on one RF (eRF1) to initiate peptide release at all three stop codons. Based on several structural as well as biochemical studies, interactions between mRNA, tRNA, and rRNA have been proposed to be required for stop codon recognition. In this study, the influence of these interactions was investigated by using chemically modified stop codons. Single functional groups within stop codon nucleotides were substituted to weaken or completely eliminate specific interactions between the respective mRNA and RFs. Our findings provide detailed insight into the recognition mode of bacterial and eukaryotic RFs, thereby revealing the chemical groups of nucleotides that define the identity of stop codons and provide the means to discriminate against noncognate stop codons or UGG sense codons., Competing Interests: The authors declare no conflict of interest., (Copyright © 2018 the Author(s). Published by PNAS.)
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- 2018
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118. Enteric Microbiome Markers as Early Predictors of Clinical Outcome in Allogeneic Hematopoietic Stem Cell Transplant: Results of a Prospective Study in Adult Patients.
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Mancini N, Greco R, Pasciuta R, Barbanti MC, Pini G, Morrow OB, Morelli M, Vago L, Clementi N, Giglio F, Lupo Stanghellini MT, Forcina A, Infurnari L, Marktel S, Assanelli A, Carrabba M, Bernardi M, Corti C, Burioni R, Peccatori J, Sormani MP, Banfi G, Ciceri F, and Clementi M
- Abstract
Background: Infections and graft-vs-host disease (GvHD) still represent major, not easily predictable complications in allogeneic hematopoietic stem cell transplant (allo-HSCT). Both conditions have been correlated to altered enteric microbiome profiles during the peritransplant period. The main objective of this study was to identify possible early microbiome-based markers useful in pretransplant risk stratification., Methods: Stool samples were collected from 96 consecutive patients at the beginning of the pretransplant conditioning regimen (T
0 ) and at 10 (T1 ) and 30 (T2 ) days following transplant. When significant in univariate analysis, the identified microbiome markers were used in multivariate regression analyses, together with other significant clinical variables for allo-HSCT-related risk stratification. Four main outcomes were addressed: (1) septic complications, (2) GvHD, (3) relapse of the underlying disease, and (4) mortality., Results: The presence of >5% proinflammatory Enterobacteriaceae at T0 was the only significant marker for the risk of microbiologically confirmed sepsis. Moreover, ≤10% Lachnospiraceae at T0 was the only significant factor for increased risk of overall mortality, including death from both infectious and noninfectious causes.Finally, a low bacterial alpha-diversity (Shannon index ≤ 1.3) at T1 was the only variable significantly correlating with an increased risk of GvHD within 30 days., Conclusions: Microbiome markers can be useful in the very early identification of patients at risk for major transplant-related complications, offering new tools for individualized preemptive or therapeutic strategies to improve allo-HSCT outcomes.- Published
- 2017
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119. Entry inhibition of HSV-1 and -2 protects mice from viral lethal challenge.
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Clementi N, Criscuolo E, Cappelletti F, Quaranta P, Pistello M, Diotti RA, Sautto GA, Tarr AW, Mailland F, Concas D, Burioni R, Clementi M, and Mancini N
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- Animals, Antibodies, Monoclonal administration & dosage, Antibodies, Monoclonal immunology, Antibodies, Viral immunology, Antibodies, Viral pharmacology, Chlorocebus aethiops, Cross Protection immunology, Disease Models, Animal, Eye pathology, Female, HEK293 Cells, Herpes Simplex transmission, Herpes Simplex virology, Herpesvirus 1, Human pathogenicity, Herpesvirus 2, Human pathogenicity, Humans, Kidney pathology, Mice, Mice, Inbred C57BL, Neutralization Tests, Vero Cells, Viral Envelope Proteins immunology, Viral Plaque Assay, Virus Replication drug effects, Antibodies, Monoclonal pharmacology, Herpes Simplex immunology, Herpes Simplex prevention & control, Herpesvirus 1, Human drug effects, Herpesvirus 1, Human immunology, Herpesvirus 2, Human drug effects, Herpesvirus 2, Human immunology, Virus Internalization drug effects
- Abstract
The present study focused on inhibition of HSV-1 and -2 replication and pathogenesis in vitro and in vivo, through the selective targeting of the envelope glycoprotein D. Firstly, a human monoclonal antibody (Hu-mAb#33) was identified that could neutralise both HSV-1 and -2 at nM concentrations, including clinical isolates from patients affected by different clinical manifestations and featuring different susceptibility to acyclovir in vitro. Secondly, the potency of inhibition of both infection by cell-free viruses and cell-to-cell virus transmission was also assessed. Finally, mice receiving a single systemic injection of Hu-mAb#33 were protected from death and severe clinical manifestations following both ocular and vaginal HSV-1 and -2 lethal challenge. These results pave the way for further studies reassessing the importance of HSV entry as a novel target for therapeutic intervention and inhibition of cell-to-cell virus transmission., (Copyright © 2017 Elsevier B.V. All rights reserved.)
- Published
- 2017
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120. A Biologically-validated HCV E1E2 Heterodimer Structural Model.
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Castelli M, Clementi N, Pfaff J, Sautto GA, Diotti RA, Burioni R, Doranz BJ, Dal Peraro M, Clementi M, and Mancini N
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- Computational Biology methods, Computer Simulation, Disulfides chemistry, Epitope Mapping, Hepacivirus chemistry, Hepacivirus genetics, Models, Molecular, Mutation, Protein Conformation, Protein Multimerization, Viral Envelope Proteins genetics, Virus Internalization, Hepacivirus metabolism, Viral Envelope Proteins chemistry, Viral Envelope Proteins metabolism
- Abstract
The design of vaccine strategies and the development of drugs targeting the early stages of Hepatitis C virus (HCV) infection are hampered by the lack of structural information about its surface glycoproteins E1 and E2, the two constituents of HCV entry machinery. Despite the recent crystal resolution of limited versions of both proteins in truncated form, a complete picture of the E1E2 complex is still missing. Here we combined deep computational analysis of E1E2 secondary, tertiary and quaternary structure with functional and immunological mutational analysis across E1E2 in order to propose an in silico model for the ectodomain of the E1E2 heterodimer. Our model describes E1-E2 ectodomain dimerization interfaces, provides a structural explanation of E1 and E2 immunogenicity and sheds light on the molecular processes and disulfide bridges isomerization underlying the conformational changes required for fusion. Comprehensive alanine mutational analysis across 553 residues of E1E2 also resulted in identifying the epitope maps of diverse mAbs and the disulfide connectivity underlying E1E2 native conformation. The predicted structure unveils E1 and E2 structures in complex, thus representing a step towards the rational design of immunogens and drugs inhibiting HCV entry.
- Published
- 2017
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121. Atomic mutagenesis at the ribosomal decoding site.
- Author
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Schrode P, Huter P, Clementi N, and Erlacher M
- Subjects
- Aminoglycosides pharmacology, Escherichia coli genetics, Escherichia coli metabolism, Protein Biosynthesis drug effects, RNA, Ribosomal, RNA, Ribosomal, 16S genetics, RNA, Transfer, Binding Sites, Codon, Mutagenesis, RNA, Messenger genetics, RNA, Messenger metabolism, Ribosomes metabolism
- Abstract
Ribosomal decoding is an essential process in every living cell. During protein synthesis the 30S ribosomal subunit needs to accomplish binding and accurate decoding of mRNAs. From mutational studies and high-resolution crystal structures nucleotides G530, A1492 and A1493 of the 16S rRNA came into focus as important elements for the decoding process. Recent crystallographic data challenged the so far accepted model for the decoding mechanism. To biochemically investigate decoding in greater detail we applied an in vitro reconstitution approach to modulate single chemical groups at A1492 and A1493. The modified ribosomes were subsequently tested for their ability to efficiently decode the mRNA. Unexpectedly, the ribosome was rather tolerant toward modifications of single groups either at the base or at the sugar moiety in terms of translation activity. Concerning translation fidelity, the elimination of single chemical groups involved in a hydrogen bonding network between the tRNA, mRNA and rRNA did not change the accuracy of the ribosome. These results indicate that the contribution of those chemical groups and the formed hydrogen bonds are not crucial for ribosomal decoding.
- Published
- 2017
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122. Rational Dosing Strategies of Colistin: What About Resistance?
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Mancini N, Clementi N, Burioni R, and Clementi M
- Subjects
- Anti-Bacterial Agents therapeutic use, Humans, Colistin administration & dosage, Drug Resistance, Multiple, Bacterial drug effects
- Published
- 2016
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123. Novel therapeutic investigational strategies to treat severe and disseminated HSV infections suggested by a deeper understanding of in vitro virus entry processes.
- Author
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Clementi N, Criscuolo E, Cappelletti F, Burioni R, Clementi M, and Mancini N
- Subjects
- Animals, Antiviral Agents pharmacology, Herpesvirus 1, Human drug effects, Herpesvirus 1, Human physiology, Herpesvirus 2, Human drug effects, Herpesvirus 2, Human physiology, Humans, Virus Internalization drug effects, Antiviral Agents therapeutic use, Herpes Simplex drug therapy
- Abstract
The global burden of herpes simplex virus (HSV) legitimates the critical need to develop new prevention strategies, such as drugs and vaccines that are able to fight either primary HSV infections or reactivations. Moreover, the ever-growing number of patients receiving transplants increases the number of severe HSV infections that are unresponsive to current therapies. Finally, the high global incidence of genital HSV-2 infection increases the risk of perinatal transmission to newborns, in which disseminated infection or central nervous system (CNS) involvement is frequent, with associated high morbidity and mortality rates. There are several key features shared by novel anti-HSV drugs, from currently available optimized drugs to small molecules able to interfere with various virus replication steps. However, several virological aspects of the disease and associated clinical needs highlight why an ideal anti-HSV drug has yet to be developed., (Copyright © 2016 Elsevier Ltd. All rights reserved.)
- Published
- 2016
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124. Chimeric antigen receptor (CAR)-engineered T cells redirected against hepatitis C virus (HCV) E2 glycoprotein.
- Author
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Sautto GA, Wisskirchen K, Clementi N, Castelli M, Diotti RA, Graf J, Clementi M, Burioni R, Protzer U, and Mancini N
- Subjects
- Antibodies, Monoclonal, Humanized immunology, Antibodies, Monoclonal, Humanized therapeutic use, Cells, Cultured, Hepatitis C immunology, Hepatitis C virology, Hepatocytes immunology, Hepatocytes virology, Humans, Cell Engineering methods, Hepacivirus immunology, Hepatitis C therapy, Immunotherapy methods, Receptors, Antigen, T-Cell immunology, T-Lymphocytes immunology, Viral Envelope Proteins immunology
- Abstract
Objective: The recent availability of novel antiviral drugs has raised new hope for a more effective treatment of hepatitis C virus (HCV) infection and its severe sequelae. However, in the case of non-responding or relapsing patients, alternative strategies are needed. To this end we have used chimeric antigen receptors (CARs), a very promising approach recently used in several clinical trials to redirect primary human T cells against different tumours. In particular, we designed the first CARs against HCV targeting the HCV/E2 glycoprotein (HCV/E2)., Design: Anti-HCV/E2 CARs were composed of single-chain variable fragments (scFvs) obtained from a broadly cross-reactive and cross-neutralising human monoclonal antibody (mAb), e137, fused to the intracellular signalling motif of the costimulatory CD28 molecule and the CD3ζ domain. Activity of CAR-grafted T cells was evaluated in vitro against HCV/E2-transfected cells as well as hepatocytes infected with cell culture-derived HCV (HCVcc)., Results: In this proof-of-concept study, retrovirus-transduced human T cells expressing anti-HCV/E2 CARs were endowed with specific antigen recognition accompanied by degranulation and secretion of proinflammatory and antiviral cytokines, such as interferon γ, interleukin 2 and tumour necrosis factor α. Moreover, CAR-grafted T cells were capable of lysing target cells of both hepatic and non-hepatic origin expressing on their surface the HCV/E2 glycoproteins of the most clinically relevant genotypes, including 1a, 1b, 2a, 3a, 4 and 5. Finally, and more importantly, they were capable of lysing HCVcc-infected hepatocytes., Conclusions: Clearance of HCV-infected cells is a major therapeutic goal in chronic HCV infection, and adoptive transfer of anti-HCV/E2 CARs-grafted T cells represents a promising new therapeutic tool., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/)
- Published
- 2016
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125. Nucleotide modifications within bacterial messenger RNAs regulate their translation and are able to rewire the genetic code.
- Author
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Hoernes TP, Clementi N, Faserl K, Glasner H, Breuker K, Lindner H, Hüttenhofer A, and Erlacher MD
- Subjects
- 5-Methylcytosine metabolism, Adenosine genetics, Adenosine metabolism, Codon, Escherichia coli genetics, Methyltransferases genetics, Protein Biosynthesis, Pseudouridine metabolism, RNA chemistry, RNA metabolism, RNA, Bacterial metabolism, RNA, Messenger metabolism, Adenosine analogs & derivatives, Pseudouridine genetics, RNA, Bacterial genetics, RNA, Messenger genetics
- Abstract
Nucleotide modifications within RNA transcripts are found in every organism in all three domains of life. 6-methyladeonsine (m(6)A), 5-methylcytosine (m(5)C) and pseudouridine (Ψ) are highly abundant nucleotide modifications in coding sequences of eukaryal mRNAs, while m(5)C and m(6)A modifications have also been discovered in archaeal and bacterial mRNAs. Employing in vitro translation assays, we systematically investigated the influence of nucleotide modifications on translation. We introduced m(5)C, m(6)A, Ψ or 2'-O-methylated nucleotides at each of the three positions within a codon of the bacterial ErmCL mRNA and analyzed their influence on translation. Depending on the respective nucleotide modification, as well as its position within a codon, protein synthesis remained either unaffected or was prematurely terminated at the modification site, resulting in reduced amounts of the full-length peptide. In the latter case, toeprint analysis of ribosomal complexes was consistent with stalling of translation at the modified codon. When multiple nucleotide modifications were introduced within one codon, an additive inhibitory effect on translation was observed. We also identified the m(5)C modification to alter the amino acid identity of the corresponding codon, when positioned at the second codon position. Our results suggest a novel mode of gene regulation by nucleotide modifications in bacterial mRNAs., (© The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.)
- Published
- 2016
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126. Heterosubtypic protection conferred by the human monoclonal antibody PN-SIA28 against influenza A virus lethal infections in mice.
- Author
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Retamal M, Abed Y, Rhéaume C, Cappelletti F, Clementi N, Mancini N, Clementi M, Burioni R, and Boivin G
- Subjects
- Animals, Antiviral Agents therapeutic use, Female, Humans, Influenza A virus drug effects, Mice, Mice, Inbred BALB C, Antibodies, Monoclonal therapeutic use, Influenza A virus pathogenicity, Influenza, Human drug therapy, Orthomyxoviridae Infections drug therapy
- Abstract
PN-SIA28 is a human monoclonal antibody (Hu-MAb) targeting highly conserved epitopes within the stem portion of the influenza virus hemagglutinin (HA) (N. Clementi, et al, PLoS One 6:e28001, 2011, http://dx.doi.org/10.1371/journal.pone.0028001). Previous in vitro studies demonstrated PN-SIA28 neutralizing activities against phylogenetically divergent influenza A subtypes. In this study, the protective activity of PN-SIA28 was evaluated in mice inoculated with lethal influenza A/WSN/33 (H1N1), A/Quebec/144147/09 (H1N1)pdm09, and A/Victoria/3/75 (H3N2) viruses. At 24 h postinoculation (p.i.), animals received PN-SIA28 intraperitoneally (1 or 10 mg/kg of body weight) or 10 mg/kg of unrelated Hu-MAb (mock). Body weight loss and mortality rate (MR) were recorded for 14 days postinfection (p.i.). Lung viral titers (LVT) were determined at day 5 p.i. In A/WSN/33 (H1N1)-infected groups, all untreated and mock-receiving mice died, whereas MRs of 87.5% and 25% were observed in mice that received PN-SIA28 1 and 10 mg/kg, respectively. In influenza A(H1N1) pdm09-infected groups, an MR of 75% was recorded for untreated and mock-treated groups, whereas the PN-SIA28 1-mg/kg and 10-mg/kg groups had rates of 62.5% and 0%, respectively. In A/Victoria/3/75 (H3N2)-infected animals, untreated and mock-treated animals had MRs of 37.5% and 25%, respectively, and no mortalities were recorded after PN-SIA28 treatments. Accordingly, PN-SIA28 treatments significantly reduced weight losses and resulted in a ≥ 1-log reduction in LVT compared to the control in all infection groups. This study confirms that antibodies targeting highly conserved epitopes in the influenza HA stem region, like PN-SIA28, not only neutralize influenza A viruses of clinically relevant subtypes in vitro but also, more importantly, protect from a lethal influenza virus challenge in vivo., (Copyright © 2015, American Society for Microbiology. All Rights Reserved.)
- Published
- 2015
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127. Virus-induced preferential antibody gene-usage and its importance in humoral autoimmunity.
- Author
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Cappelletti F, Clementi N, Mancini N, Clementi M, and Burioni R
- Subjects
- Antibodies, Viral immunology, Autoimmune Diseases etiology, Host-Pathogen Interactions, Humans, Virus Diseases complications, Autoimmune Diseases immunology, Virus Diseases immunology
- Abstract
It is known that even the adaptive components of the immune system are based on genetic traits common to all individuals, and that diversity is shaped by the lifelong contacts with different non-self antigens, including those found on infectious pathogens. Besides the individual differences, some of these common traits may be more prone to react against a given antigen, and this may be exploited by the infectious pathogens. Indeed, viral infections can deregulate immune response by subverting antibody (Ab) gene usage, leading to the overexpression of specific Ab subfamilies. This overexpression often results in a protective antiviral response but, in some cases, also correlates with a higher likelihood of developing humoral autoimmune disorders. These aspects of virus-induced autoimmunity have never been thoroughly reviewed, and this is the main purpose of this review. An accurate examination of virus specific Ab subfamilies elicited during infections may help further characterize the complex interplay between viruses and the humoral immune response, and be useful in the design of future monoclonal antibody (mAb)-based anti-infective prophylactic and therapeutic strategies., (Copyright © 2015 Elsevier Ltd. All rights reserved.)
- Published
- 2015
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128. The integrity of the G2421-C2395 base pair in the ribosomal E-site is crucial for protein synthesis.
- Author
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Koch M, Clementi N, Rusca N, Vögele P, Erlacher M, and Polacek N
- Subjects
- Base Pairing, Mutagenesis, Protein Biosynthesis, RNA, Messenger metabolism, RNA, Transfer metabolism, Ribosomes metabolism, Thermus chemistry, Thermus cytology
- Abstract
During the elongation cycle of protein biosynthesis, tRNAs traverse through the ribosome by consecutive binding to the 3 ribosomal binding sites (A-, P-, and E- sites). While the ribosomal A- and P-sites have been functionally well characterized in the past, the contribution of the E-site to protein biosynthesis is still poorly understood in molecular terms. Previous studies suggested an important functional interaction of the terminal residue A76 of E-tRNA with the nucleobase of the universally conserved 23S rRNA residue C2394. Using an atomic mutagenesis approach to introduce non-natural nucleoside analogs into the 23S rRNA, we could show that removal of the nucleobase or the ribose 2'-OH at C2394 had no effect on protein synthesis. On the other hand, our data disclose the importance of the highly conserved E-site base pair G2421-C2395 for effective translation. Ribosomes with a disrupted G2421-C2395 base pair are defective in tRNA binding to the E-site. This results in an impaired translation of genuine mRNAs, while homo-polymeric templates are not affected. Cumulatively our data emphasize the importance of E-site tRNA occupancy and in particular the intactness of the 23S rRNA base pair G2421-C2395 for productive protein biosynthesis.
- Published
- 2015
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129. Adoptive T-cell therapy in the treatment of viral and opportunistic fungal infections.
- Author
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Mancini N, Marrone L, Clementi N, Sautto GA, Clementi M, and Burioni R
- Subjects
- Humans, Immunocompromised Host, Adoptive Transfer, Mycoses therapy, Opportunistic Infections therapy, T-Lymphocytes immunology, Virus Diseases therapy
- Abstract
Viral infections and opportunistic fungal pathogens represent a major menace for immunocompromised patients. Despite the availability of antifungal and antiviral drugs, mortality in these patients remains high, underlining the need of novel therapeutic options based on completely different strategies. This review describes the potential of several T-cell-based therapeutic approaches in the prophylaxis and treatment of infectious diseases with a particular focus on persistent viral infections and opportunistic fungal infections, as these mostly affect immunocompromised patients.
- Published
- 2015
- Full Text
- View/download PDF
130. HCV E2 core structures and mAbs: something is still missing.
- Author
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Castelli M, Clementi N, Sautto GA, Pfaff J, Kahle KM, Barnes T, Doranz BJ, Dal Peraro M, Clementi M, Burioni R, and Mancini N
- Subjects
- Animals, Antibodies, Monoclonal pharmacology, Cysteine chemistry, Disulfides chemistry, Hepacivirus pathogenicity, Humans, Models, Molecular, Protein Conformation, Viral Envelope Proteins metabolism, Viral Envelope Proteins chemistry
- Abstract
The lack of structural information on hepatitis C virus (HCV) surface proteins has so far hampered the development of effective vaccines. Recently, two crystallographic structures have described the core portion (E2c) of E2 surface glycoprotein, the primary mediator of HCV entry. Despite the importance of these studies, the E2 overall structure is still unknown and, most importantly, several biochemical and functional studies are in disagreement with E2c structures. Here, the main literature will be discussed and an alternative disulfide bridge pattern will be proposed, based on unpublished human monoclonal antibody reactivity. A modeling strategy aiming at recapitulating the available structural and functional studies of E2 will also be proposed., (Copyright © 2014 Elsevier Ltd. All rights reserved.)
- Published
- 2014
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131. Cloning of the first human anti-JCPyV/VP1 neutralizing monoclonal antibody: epitope definition and implications in risk stratification of patients under natalizumab therapy.
- Author
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Diotti RA, Mancini N, Clementi N, Sautto G, Moreno GJ, Criscuolo E, Cappelletti F, Man P, Forest E, Remy L, Giannecchini S, Clementi M, and Burioni R
- Subjects
- Antibodies, Monoclonal genetics, Antibodies, Monoclonal, Humanized adverse effects, Antibodies, Neutralizing genetics, Antibodies, Viral genetics, Capsid Proteins immunology, Cloning, Molecular, Epitopes genetics, Epitopes immunology, Humans, Leukoencephalopathy, Progressive Multifocal immunology, Multiple Sclerosis therapy, Natalizumab, Neutralization Tests methods, Antibodies, Monoclonal immunology, Antibodies, Monoclonal, Humanized therapeutic use, Antibodies, Neutralizing immunology, Antibodies, Viral immunology, Capsid Proteins antagonists & inhibitors, Leukoencephalopathy, Progressive Multifocal prevention & control, Polyomavirus immunology
- Abstract
JC virus (JCPyV) has gained novel clinical importance as cause of progressive multifocal leukoencephalopathy (PML), a rare demyelinating disease recently associated to immunomodulatory drugs, such as natalizumab used in multiple sclerosis (MS) cases. Little is known about the mechanisms leading to PML, and this makes the need of PML risk stratification among natalizumab-treated patients very compelling. Clinical and laboratory-based risk-stratification markers have been proposed, one of these is represented by the JCPyV-seropositive status, which includes about 54% of MS patients. We recently proposed to investigate the possible protective role of neutralizing humoral immune response in preventing JCPyV reactivation. In this proof-of-concept study, by cloning the first human monoclonal antibody (GRE1) directed against a neutralizing epitope on JCPyV/VP1, we optimized a robust anti-JCPyV neutralization assay. This allowed us to evaluate the neutralizing activity in JCPyV-positive sera from MS patients, demonstrating the lack of correlation between the level of anti-JCPyV antibody and anti-JCPyV neutralizing activity. Relevant consequences may derive from future clinical studies induced by these findings; indeed the study of the serum anti-JCPyV neutralizing activity could allow not only a better risk stratification of the patients during natalizumab treatment, but also a better understanding of the pathophysiological mechanisms leading to PML, highlighting the contribution of peripheral versus central nervous system JCPyV reactivation. Noteworthy, the availability of GRE1 could allow the design of novel immunoprophylactic strategies during the immunomodulatory treatment., (Copyright © 2014 Elsevier B.V. All rights reserved.)
- Published
- 2014
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132. Potential impact of a microarray-based nucleic acid assay for rapid detection of Gram-negative bacteria and resistance markers in positive blood cultures.
- Author
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Mancini N, Infurnari L, Ghidoli N, Valzano G, Clementi N, Burioni R, and Clementi M
- Subjects
- Gram-Negative Bacteria drug effects, Gram-Negative Bacteria genetics, Humans, Pilot Projects, Predictive Value of Tests, Sensitivity and Specificity, Bacteremia diagnosis, Drug Resistance, Bacterial, Gram-Negative Bacteria isolation & purification, Gram-Negative Bacterial Infections diagnosis, Microarray Analysis methods, Molecular Diagnostic Techniques methods
- Abstract
We evaluated the Verigene Gram-negative blood culture (BC-GN) test, a microarray that detects Gram-negative bacteria and several resistance genes. A total of 102 positive blood cultures were tested, and the BC-GN test correctly identified 97.9% of the isolates within its panel. Resistance genes (CTX-M, KPC, VIM, and OXA genes) were detected in 29.8% of the isolates, with positive predictive values of 95.8% (95% confidence interval [CI], 87.7% to 98.9%) in Enterobacteriaceae and 100% (95% CI, 75.9% to 100%) in Pseudomonas aeruginosa and negative predictive values of 100% (95% CI, 93.9% to 100%) and 78.6% (95% CI, 51.0% to 93.6%), respectively.
- Published
- 2014
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133. Epitope mapping by epitope excision, hydrogen/deuterium exchange, and peptide-panning techniques combined with in silico analysis.
- Author
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Clementi N, Mancini N, Criscuolo E, Cappelletti F, Clementi M, and Burioni R
- Subjects
- Deuterium, Peptides chemistry, Epitope Mapping methods, Epitopes chemistry, Hydrogen chemistry
- Abstract
The fine characterization of protective B cell epitopes plays a pivotal role in the development of novel vaccines. The development of epitope-based vaccines, in fact, cannot be possible without a clear definition of the antigenic regions involved in the binding between the protective antibody (Ab) and its molecular target. To achieve this result, different epitope-mapping approaches have been widely described (Clementi et al. Drug Discov Today 18(9-10):464-471, 2013). Nowadays, the best way to characterize an Ab bound region is still the resolution of Ab-antigen (Ag) co-crystal structure. Unfortunately, the crystallization approaches are not always feasible. However, different experimental strategies aimed to predict Ab-Ag interaction and followed by in silico analysis of the results may be good surrogate approaches to achieve this result. Here, we review few experimental techniques followed by the use of "basic" informatics tools for the analysis of the results.
- Published
- 2014
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134. Comparative evaluation of the Bruker Biotyper and Vitek MS matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry systems for identification of yeasts of medical importance.
- Author
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Mancini N, De Carolis E, Infurnari L, Vella A, Clementi N, Vaccaro L, Ruggeri A, Posteraro B, Burioni R, Clementi M, and Sanguinetti M
- Subjects
- Diagnostic Errors statistics & numerical data, Humans, Time Factors, Yeasts chemistry, Yeasts isolation & purification, Yeasts metabolism, Microbiological Techniques methods, Mycological Typing Techniques methods, Mycology methods, Mycoses diagnosis, Mycoses microbiology, Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization methods, Yeasts classification
- Abstract
We report the first comparative evaluation between the Bruker Biotyper MS (BMS) and the Vitek MS (VMS) for the identification of yeasts. The rate of correct identifications at the species level was comparable using the commercial databases (89.8% versus 84.3%; P = 0.712), but higher for BMS using an in-house-extended database (100% versus 84.3%; P = 0.245). Importantly, the rate of misidentification was significantly higher for VMS (1% versus 12.1%; P < 0.0001), including the rate of major errors (0% versus 4.5%; P = 0.0036).
- Published
- 2013
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135. Characterization of epitopes recognized by monoclonal antibodies: experimental approaches supported by freely accessible bioinformatic tools.
- Author
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Clementi N, Mancini N, Castelli M, Clementi M, and Burioni R
- Subjects
- Antibodies, Monoclonal chemistry, Epitope Mapping, Epitopes chemistry, X-Ray Diffraction, Antibodies, Monoclonal immunology, Computational Biology methods, Epitopes immunology
- Abstract
Monoclonal antibodies (mAbs) have been used successfully both in research and for clinical purposes. The possible use of protective mAbs directed against different microbial pathogens is currently being considered. The fine definition of the epitope recognized by a protective mAb is an important aspect to be considered for possible development in epitope-based vaccinology. The most accurate approach to this is the X-ray resolution of mAb/antigen crystal complex. Unfortunately, this approach is not always feasible. Under this perspective, several surrogate epitope mapping strategies based on the use of bioinformatics have been developed. In this article, we review the most common, freely accessible, bioinformatic tools used for epitope characterization and provide some basic examples of molecular visualization, editing and computational analysis., (Copyright © 2012 Elsevier Ltd. All rights reserved.)
- Published
- 2013
- Full Text
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136. Acute respiratory distress in a neutropenic febrile patient after hematopoietic cell transplantation.
- Author
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Dvir R, Mancini N, Assanelli A, Racca S, Rolla S, Clementi N, Piemontese S, Ciceri F, Burioni R, and Clementi M
- Subjects
- Bronchoalveolar Lavage Fluid parasitology, Fatal Outcome, Fever blood, Fever immunology, Fever parasitology, Humans, Immunosuppressive Agents therapeutic use, Leukemia, Myeloid, Acute drug therapy, Leukemia, Myeloid, Acute surgery, Male, Middle Aged, Neutropenia etiology, Neutropenia immunology, Neutropenia parasitology, Radiography, Thoracic, Respiratory Distress Syndrome blood, Toxoplasma isolation & purification, Toxoplasmosis diagnosis, Toxoplasmosis immunology, Fever etiology, Hematopoietic Stem Cell Transplantation adverse effects, Neutropenia complications, Respiratory Distress Syndrome etiology, Toxoplasmosis etiology
- Published
- 2013
- Full Text
- View/download PDF
137. Peptide-based vaccinology: experimental and computational approaches to target hypervariable viruses through the fine characterization of protective epitopes recognized by monoclonal antibodies and the identification of T-cell-activating peptides.
- Author
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Castelli M, Cappelletti F, Diotti RA, Sautto G, Criscuolo E, Dal Peraro M, and Clementi N
- Subjects
- Animals, Antibodies, Monoclonal immunology, Antibodies, Viral immunology, Epitopes, B-Lymphocyte chemistry, Epitopes, B-Lymphocyte immunology, Epitopes, T-Lymphocyte chemistry, Epitopes, T-Lymphocyte immunology, Humans, Immunity, Humoral, Lymphocyte Activation immunology, Peptides chemistry, Peptides immunology, T-Lymphocyte Subsets immunology, Vaccines, Subunit immunology, Viral Vaccines immunology
- Abstract
Defining immunogenic domains of viral proteins capable of eliciting a protective immune response is crucial in the development of novel epitope-based prophylactic strategies. This is particularly important for the selective targeting of conserved regions shared among hypervariable viruses. Studying postinfection and postimmunization sera, as well as cloning and characterization of monoclonal antibodies (mAbs), still represents the best approach to identify protective epitopes. In particular, a protective mAb directed against conserved regions can play a key role in immunogen design and in human therapy as well. Experimental approaches aiming to characterize protective mAb epitopes or to identify T-cell-activating peptides are often burdened by technical limitations and can require long time to be correctly addressed. Thus, in the last decade many epitope predictive algorithms have been developed. These algorithms are continually evolving, and their use to address the empirical research is widely increasing. Here, we review several strategies based on experimental techniques alone or addressed by in silico analysis that are frequently used to predict immunogens to be included in novel epitope-based vaccine approaches. We will list the main strategies aiming to design a new vaccine preparation conferring the protection of a neutralizing mAb combined with an effective cell-mediated response.
- Published
- 2013
- Full Text
- View/download PDF
138. JC polyomavirus (JCV) and monoclonal antibodies: friends or potential foes?
- Author
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Diotti RA, Nakanishi A, Clementi N, Mancini N, Criscuolo E, Solforosi L, and Clementi M
- Subjects
- Antibodies, Monoclonal therapeutic use, Humans, Immune System, JC Virus physiology, Leukoencephalopathy, Progressive Multifocal epidemiology, Leukoencephalopathy, Progressive Multifocal therapy, Antibodies, Monoclonal immunology, JC Virus immunology, Leukoencephalopathy, Progressive Multifocal immunology
- Abstract
Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease of the central nervous system (CNS), observed in immunodeficient patients and caused by JC virus ((JCV), also called JC polyomavirus (JCPyV)). After the HIV pandemic and the introduction of immunomodulatory therapy, the PML incidence significantly increased. The correlation between the use of natalizumab, a drug used in multiple sclerosis (MS), and the PML development of particular relevance. The high incidence of PML in natalizumab-treated patients has highlighted the importance of two factors: the need of PML risk stratification among natalizumab-treated patients and the need of effective therapeutic options. In this review, we discuss these two needs under the light of the major viral models of PML etiopathogenesis.
- Published
- 2013
- Full Text
- View/download PDF
139. Influenza B-cells protective epitope characterization: a passkey for the rational design of new broad-range anti-influenza vaccines.
- Author
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Clementi N, Criscuolo E, Castelli M, Mancini N, Clementi M, and Burioni R
- Subjects
- Animals, Antibodies, Monoclonal immunology, Antibodies, Neutralizing immunology, Antigens, Viral chemistry, Cross Reactions immunology, Epitopes, B-Lymphocyte chemistry, Hemagglutinin Glycoproteins, Influenza Virus chemistry, Hemagglutinin Glycoproteins, Influenza Virus immunology, Humans, Influenza A virus classification, Influenza A virus genetics, Influenza Vaccines immunology, Influenza, Human prevention & control, Antigens, Viral immunology, B-Lymphocytes immunology, Epitopes, B-Lymphocyte immunology, Influenza A virus immunology, Influenza, Human immunology
- Abstract
The emergence of new influenza strains causing pandemics represents a serious threat to human health. From 1918, four influenza pandemics occurred, caused by H1N1, H2N2 and H3N2 subtypes. Moreover, in 1997 a novel influenza avian strain belonging to the H5N1 subtype infected humans. Nowadays, even if its transmission is still circumscribed to avian species, the capability of the virus to infect humans directly from avian reservoirs can result in fatalities. Moreover, the risk that this or novel avian strains could adapt to inter-human transmission, the development of resistance to anti-viral drugs and the lack of an effective prevention are all incumbent problems for the world population. In this scenario, the identification of broadly neutralizing monoclonal antibodies (mAbs) directed against conserved regions shared among influenza isolates has raised hopes for the development of monoclonal antibody-based immunotherapy and "universal" anti-influenza vaccines.
- Published
- 2012
- Full Text
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140. Broad-range neutralizing anti-influenza A human monoclonal antibodies: new perspectives in therapy and prophylaxis.
- Author
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Clementi N, Criscuolo E, Castelli M, and Clementi M
- Subjects
- Animals, Antibodies, Monoclonal immunology, Antibodies, Neutralizing immunology, Antibodies, Viral immunology, Humans, Influenza A virus genetics, Influenza, Human drug therapy, Influenza, Human immunology, Antibodies, Monoclonal therapeutic use, Antibodies, Neutralizing therapeutic use, Antibodies, Viral therapeutic use, Influenza A virus immunology, Influenza, Human prevention & control
- Abstract
Broadly neutralizing monoclonal antibodies (mAbs) directed against different subtypes of influenza A viruses are novel tools for the potential development of effective anti-influenza prophylactic and therapeutic strategies. In both cases, the main candidates for passive transfer and new vaccine development are represented by protective mAbs directed against influenza hemagglutinin (HA). A large number of mAbs directed against influenza HA has been developed to date. However, even if they can be useful and contribute to develop new vaccinal strategies, only few of them can be a good candidate for human administration. In this review, we will describe the most relevant human mAb directed against influenza HA able to recognize highly divergent influenza isolates and possibly useful for human therapy and prophylaxis.
- Published
- 2012
141. Neutralization interfering antibodies: a "novel" example of humoral immune dysfunction facilitating viral escape?
- Author
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Nicasio M, Sautto G, Clementi N, Diotti RA, Criscuolo E, Castelli M, Solforosi L, Clementi M, and Burioni R
- Subjects
- Humans, Antibodies, Neutralizing immunology, Antibodies, Viral immunology, Immune Evasion, Virus Diseases immunology, Viruses immunology, Viruses pathogenicity
- Abstract
The immune response against some viral pathogens, in particular those causing chronic infections, is often ineffective notwithstanding a robust humoral neutralizing response. Several evasion mechanisms capable of subverting the activity of neutralizing antibodies (nAbs) have been described. Among them, the elicitation of non-neutralizing and interfering Abs has been hypothesized. Recently, this evasion mechanism has acquired an increasing interest given its possible impact on novel nAb-based antiviral therapeutic and prophylactic approaches. In this review, we illustrate the mechanisms of Ab-mediated interference and the viral pathogens described in literature as able to adopt this "novel" evasion strategy.
- Published
- 2012
- Full Text
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142. A phage display vector optimized for the generation of human antibody combinatorial libraries and the molecular cloning of monoclonal antibody fragments.
- Author
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Solforosi L, Mancini N, Canducci F, Clementi N, Sautto GA, Diotti RA, Clementi M, and Burioni R
- Subjects
- Animals, Cell Line, DNA, Complementary genetics, Escherichia coli genetics, Humans, Immunoglobulin Fab Fragments immunology, Influenza A Virus, H1N1 Subtype immunology, Lac Operon, Male, Middle Aged, Nucleocapsid Proteins, Promoter Regions, Genetic, Protein Sorting Signals, RNA-Binding Proteins genetics, Recombinant Proteins genetics, Viral Core Proteins genetics, Cloning, Molecular methods, Genetic Vectors, Immunoglobulin Fab Fragments biosynthesis, Peptide Library
- Abstract
A novel phagemid vector, named pCM, was optimized for the cloning and display of antibody fragment (Fab) libraries on the surface of filamentous phage. This vector contains two long DNA "stuffer" fragments for easier differentiation of the correctly cut forms of the vector. Moreover, in pCM the fragment at the heavy-chain cloning site contains an acid phosphatase-encoding gene allowing an easy distinction of the Escherichia coli cells containing the unmodified form of the phagemid versus the heavy-chain fragment coding cDNA. In pCM transcription of heavy-chain Fd/gene III and light chain is driven by a single lacZ promoter. The light chain is directed to the periplasm by the ompA signal peptide, whereas the heavy-chain Fd/coat protein III is trafficked by the pelB signal peptide. The phagemid pCM was used to generate a human combinatorial phage display antibody library that allowed the selection of a monoclonal Fab fragment antibody directed against the nucleoprotein (NP) of Influenza A virus.
- Published
- 2012
143. Characterisation of the contribution of the GABA-benzodiazepine α1 receptor subtype to [(11)C]Ro15-4513 PET images.
- Author
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Myers JF, Rosso L, Watson BJ, Wilson SJ, Kalk NJ, Clementi N, Brooks DJ, Nutt DJ, Turkheimer FE, and Lingford-Hughes AR
- Subjects
- Adult, Affinity Labels administration & dosage, Brain diagnostic imaging, Double-Blind Method, Humans, Male, Middle Aged, Protein Binding, Protein Subunits agonists, Protein Subunits metabolism, Pyridines administration & dosage, Radiography, Zolpidem, Azides administration & dosage, Benzodiazepines administration & dosage, Brain metabolism, GABA-A Receptor Agonists administration & dosage, Positron-Emission Tomography, Receptors, GABA-A metabolism
- Abstract
This positron emission tomography (PET) study aimed to further define selectivity of [(11)C]Ro15-4513 binding to the GABARα5 relative to the GABARα1 benzodiazepine receptor subtype. The impact of zolpidem, a GABARα1-selective agonist, on [(11)C]Ro15-4513, which shows selectivity for GABARα5, and the nonselective benzodiazepine ligand [(11)C]flumazenil binding was assessed in humans. Compartmental modelling of the kinetics of [(11)C]Ro15-4513 time-activity curves was used to describe distribution volume (V(T)) differences in regions populated by different GABA receptor subtypes. Those with low α5 were best fitted by one-tissue compartment models; and those with high α5 required a more complex model. The heterogeneity between brain regions suggested spectral analysis as a more appropriate method to quantify binding as it does not a priori specify compartments. Spectral analysis revealed that zolpidem caused a significant V(T) decrease (~10%) in [(11)C]flumazenil, but no decrease in [(11)C]Ro15-4513 binding. Further analysis of [(11)C]Ro15-4513 kinetics revealed additional frequency components present in regions containing both α1 and α5 subtypes compared with those containing only α1. Zolpidem reduced one component (mean±s.d.: 71%±41%), presumed to reflect α1-subtype binding, but not another (13%±22%), presumed to reflect α5. The proposed method for [(11)C]Ro15-4513 analysis may allow more accurate selective binding assays and estimation of drug occupancy for other nonselective ligands.
- Published
- 2012
- Full Text
- View/download PDF
144. Phage display-based strategies for cloning and optimization of monoclonal antibodies directed against human pathogens.
- Author
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Clementi N, Mancini N, Solforosi L, Castelli M, Clementi M, and Burioni R
- Subjects
- Animals, Antibodies, Monoclonal pharmacology, Antiviral Agents pharmacology, B-Lymphocytes physiology, Cloning, Molecular, Hepacivirus drug effects, Hepacivirus immunology, Humans, Influenza A virus drug effects, Influenza A virus immunology, Peptide Library, Research Design, Antibodies, Monoclonal genetics
- Abstract
In the last two decades, several phage display-selected monoclonal antibodies (mAbs) have been described in the literature and a few of them have managed to reach the clinics. Among these, the anti-respiratory syncytial virus (RSV) Palivizumab, a phage-display optimized mAb, is the only marketed mAb directed against microbial pathogens. Palivizumab is a clear example of the importance of choosing the most appropriate strategy when selecting or optimizing an anti-infectious mAb. From this perspective, the extreme versatility of phage-display technology makes it a useful tool when setting up different strategies for the selection of mAbs directed against human pathogens, especially when their possible clinical use is considered. In this paper, we review the principal phage display strategies used to select anti-infectious mAbs, with particular attention focused on those used against hypervariable pathogens, such as HCV and influenza viruses.
- Published
- 2012
- Full Text
- View/download PDF
145. A non-VH1-69 heterosubtypic neutralizing human monoclonal antibody protects mice against H1N1 and H5N1 viruses.
- Author
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De Marco D, Clementi N, Mancini N, Solforosi L, Moreno GJ, Sun X, Tumpey TM, Gubareva LV, Mishin V, Clementi M, and Burioni R
- Subjects
- Amino Acid Sequence, Animals, Antibodies, Monoclonal immunology, Antibodies, Viral immunology, Epitopes genetics, Epitopes immunology, Female, Hemagglutinin Glycoproteins, Influenza Virus chemistry, Hemagglutinin Glycoproteins, Influenza Virus metabolism, Hemagglutinins genetics, Hemagglutinins metabolism, Humans, Influenza A Virus, H1N1 Subtype genetics, Influenza A Virus, H5N1 Subtype genetics, Influenza Vaccines immunology, Mice, Mice, Inbred BALB C, Molecular Sequence Data, Mutagenesis, Mutation genetics, Neutralization Tests, Orthomyxoviridae Infections immunology, Orthomyxoviridae Infections virology, Protein Conformation, Sequence Homology, Amino Acid, Antibodies, Monoclonal therapeutic use, Hemagglutinin Glycoproteins, Influenza Virus immunology, Hemagglutinins immunology, Influenza A Virus, H1N1 Subtype immunology, Influenza A Virus, H5N1 Subtype immunology, Influenza Vaccines therapeutic use, Orthomyxoviridae Infections prevention & control
- Abstract
Influenza viruses are among the most important human pathogens and are responsible for annual epidemics and sporadic, potentially devastating pandemics. The humoral immune response plays an important role in the defense against these viruses, providing protection mainly by producing antibodies directed against the hemagglutinin (HA) glycoprotein. However, their high genetic variability allows the virus to evade the host immune response and the potential protection offered by seasonal vaccines. The emergence of resistance to antiviral drugs in recent years further limits the options available for the control of influenza. The development of alternative strategies for influenza prophylaxis and therapy is therefore urgently needed. In this study, we describe a human monoclonal antibody (PN-SIA49) that recognizes a highly conserved epitope located on the stem region of the HA and able to neutralize a broad spectrum of influenza viruses belonging to different subtypes (H1, H2 and H5). Furthermore, we describe its protective activity in mice after lethal challenge with H1N1 and H5N1 viruses suggesting a potential application in the treatment of influenza virus infections.
- Published
- 2012
- Full Text
- View/download PDF
146. A potential role for monoclonal antibodies in prophylactic and therapeutic treatment of influenza.
- Author
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Mancini N, Solforosi L, Clementi N, De Marco D, Clementi M, and Burioni R
- Subjects
- Animals, Antibodies, Monoclonal immunology, Humans, Influenza A virus genetics, Influenza A virus immunology, Influenza Vaccines immunology, Influenza Vaccines therapeutic use, Influenza, Human immunology, Influenza, Human virology, Viral Proteins genetics, Viral Proteins immunology, Antibodies, Monoclonal therapeutic use, Influenza A virus drug effects, Influenza, Human drug therapy, Influenza, Human prevention & control
- Abstract
The role of humoral response in the effective control of infection by influenza viruses is well known, but the protection is usually limited to the infecting or vaccinating isolate and to few related strains. Recent studies have evidenced the existence of B-cell epitopes broadly conserved among different influenza subtypes recognized by monoclonal antibodies endowed with unprecedented broad activity. In this review, all major monoclonal antibodies directed against different influenza virus proteins are reported and their potential in the design of new anti-influenza prophylactic or therapeutic strategies is discussed., (Copyright © 2011 Elsevier B.V. All rights reserved.)
- Published
- 2011
- Full Text
- View/download PDF
147. A human monoclonal antibody with neutralizing activity against highly divergent influenza subtypes.
- Author
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Clementi N, De Marco D, Mancini N, Solforosi L, Moreno GJ, Gubareva LV, Mishin V, Di Pietro A, Vicenzi E, Siccardi AG, Clementi M, and Burioni R
- Subjects
- Alanine genetics, Animals, Antibodies, Neutralizing chemistry, Cell Line, Cluster Analysis, Dogs, Glycoproteins chemistry, Hemagglutinins, Viral chemistry, Humans, Influenza, Human prevention & control, Models, Molecular, Molecular Conformation, Mutagenesis, Site-Directed, Neutralization Tests, Phylogeny, Protein Binding, Antibodies, Monoclonal chemistry, Influenza Vaccines therapeutic use, Influenza, Human metabolism, Orthomyxoviridae genetics, Orthomyxoviridae immunology
- Abstract
The interest in broad-range anti-influenza A monoclonal antibodies (mAbs) has recently been strengthened by the identification of anti-hemagglutinin (HA) mAbs endowed with heterosubtypic neutralizing activity to be used in the design of "universal" prophylactic or therapeutic tools. However, the majority of the single mAbs described to date do not bind and neutralize viral isolates belonging to highly divergent subtypes clustering into the two different HA-based influenza phylogenetic groups: the group 1 including, among others, subtypes H1, H2, H5 and H9 and the group 2 including, among others, H3 subtype. Here, we describe a human mAb, named PN-SIA28, capable of binding and neutralizing all tested isolates belonging to phylogenetic group 1, including H1N1, H2N2, H5N1 and H9N2 subtypes and several isolates belonging to group 2, including H3N2 isolates from the first period of the 1968 pandemic. Therefore, PN-SIA28 is capable of neutralizing isolates belonging to subtypes responsible of all the reported pandemics, as well as other subtypes with pandemic potential. The region recognized by PN-SIA28 has been identified on the stem region of HA and includes residues highly conserved among the different influenza subtypes. A deep characterization of PN-SIA28 features may represent a useful help in the improvement of available anti-influenza therapeutic strategies and can provide new tools for the development of universal vaccinal strategies.
- Published
- 2011
- Full Text
- View/download PDF
148. Diagnosis of co-morbid axis-I psychiatric disorders among women with newly diagnosed, untreated endocrine disorders.
- Author
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Fornaro M, Iovieno N, Clementi N, Boscaro M, Paggi F, Balercia G, Fava M, and Papakostas GI
- Subjects
- Addison Disease diagnosis, Addison Disease epidemiology, Addison Disease psychology, Adult, Comorbidity, Depressive Disorder, Major diagnosis, Depressive Disorder, Major psychology, Diabetes Mellitus diagnosis, Diabetes Mellitus epidemiology, Diabetes Mellitus psychology, Endocrine System Diseases diagnosis, Endocrine System Diseases psychology, Female, Humans, Hyperprolactinemia diagnosis, Hyperprolactinemia epidemiology, Hyperprolactinemia psychology, Hyperthyroidism diagnosis, Hyperthyroidism epidemiology, Hyperthyroidism psychology, Hypothyroidism diagnosis, Hypothyroidism epidemiology, Hypothyroidism psychology, Italy, Mental Disorders diagnosis, Mental Disorders psychology, Middle Aged, Panic Disorder diagnosis, Panic Disorder psychology, Pituitary ACTH Hypersecretion diagnosis, Pituitary ACTH Hypersecretion epidemiology, Pituitary ACTH Hypersecretion psychology, Polycystic Ovary Syndrome diagnosis, Polycystic Ovary Syndrome epidemiology, Polycystic Ovary Syndrome psychology, Risk Factors, Depressive Disorder, Major epidemiology, Endocrine System Diseases epidemiology, Mental Disorders epidemiology, Panic Disorder epidemiology
- Abstract
Objectives: To determine the prevalence of major depressive disorder (MDD) and other selected axis-I disorders among women with newly diagnosed, untreated endocrine disorders., Methods: Two hundred and eighteen consecutive women, aged 18-65, with newly diagnosed, untreated endocrine disorders were referred for potential diagnosis of co-morbid axis-I disorders with the use of the Structured Clinical Interview for Axis I-Patient Edition (SCID-P). The SCID-P was re-administered after 12 weeks., Results: At baseline, 64 (29.3%) women met criteria for at least one axis-I disorder. Women who were diagnosed with hyperthyroidism were more likely to meet criteria for generalized anxiety disorder and panic disorder than women without hyperthyroidism. Nine of 154 (5.8 %) women who did not meet criteria for an axis-I disorder at baseline met criteria for at least one axis-I disorder during follow-up. Among them, the presence of diabetes mellitus was statistically correlated with a higher probability of developing major depressive disorder at follow-up., Conclusions: Although preliminary, our findings are consistent with previous studies and suggest an increased prevalence of MDD and other axis-I disorders among women with newly diagnosed endocrine disorders, providing further evidence suggesting that women with endocrine abnormalities may be at increased risk of depression and/or anxiety disorders.
- Published
- 2010
- Full Text
- View/download PDF
149. Ribosome-associated GTPases: the role of RNA for GTPase activation.
- Author
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Clementi N and Polacek N
- Subjects
- Bacteria metabolism, GTP Phosphohydrolase-Linked Elongation Factors metabolism, GTP-Binding Proteins metabolism, Humans, Ribosomes metabolism, GTP Phosphohydrolase Activators metabolism, GTP Phosphohydrolases metabolism, RNA metabolism, Ribosomes enzymology
- Abstract
The GTPase super-family comprises a variety of G proteins found in all three domains of life. Although they are participating in completely different processes like signal transduction, protein biosynthesis and regulation of cell proliferation, they all share a highly conserved G domain and use a common mechanism for GTP hydrolysis. Exact timing in hydrolyzing the bound GTP serves as a molecular switch to initiate diverse cellular reactions. Classical GTPases depend on external proteins to fire GTP hydrolysis (GAPs), and following the GTPase reaction to exchange GDP for GTP (GEFs), converting the GTPase into the active state again. In recent years it became clear that there are many GTPases that do not follow this classical switch mode scheme. Certain ribosome-associated GTPases are not reliant on other GEF proteins to exchange GDP for GTP. Furthermore many of these G proteins are not activated by external GAPs, but by evolutionarily ancient molecules, namely by RNA.
- Published
- 2010
- Full Text
- View/download PDF
150. The role of the universally conserved A2450-C2063 base pair in the ribosomal peptidyl transferase center.
- Author
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Chirkova A, Erlacher MD, Clementi N, Zywicki M, Aigner M, and Polacek N
- Subjects
- Adenosine chemistry, Base Pairing, Base Sequence, Cytosine chemistry, Models, Molecular, Molecular Sequence Data, Mutagenesis, Peptide Elongation Factor G metabolism, Peptides metabolism, RNA, Transfer metabolism, Peptidyl Transferases chemistry, Protein Biosynthesis, RNA, Ribosomal, 23S chemistry, Ribosomes enzymology
- Abstract
Despite the fact that all 23S rRNA nucleotides that build the ribosomal peptidyl transferase ribozyme are universally conserved, standard and atomic mutagenesis studies revealed the nucleobase identities being non-critical for catalysis. This indicates that these active site residues are highly conserved for functions distinct from catalysis. To gain insight into potential contributions, we have manipulated the nucleobases via an atomic mutagenesis approach and have utilized these chemically engineered ribosomes for in vitro translation reactions. We show that most of the active site nucleobases could be removed without significant effects on polypeptide production. Our data however highlight the functional importance of the universally conserved non-Watson-Crick base pair at position A2450-C2063. Modifications that disrupt this base pair markedly impair translation activities, while having little effects on peptide bond formation, tRNA drop-off and ribosome-dependent EF-G GTPase activity. Thus it seems that disruption of the A2450-C2063 pair inhibits a reaction following transpeptidation and EF-G action during the elongation cycle. Cumulatively our data are compatible with the hypothesis that the integrity of this A-C wobble base pair is essential for effective tRNA translocation through the peptidyl transferase center during protein synthesis.
- Published
- 2010
- Full Text
- View/download PDF
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