Epitope mapping of antibodies induced with a conserved rhinovirus protein generating protective anti-rhinovirus immunity

Human rhinovirus (RV) infections are the principle cause of common colds and precipitate asthma and chronic obstructive pulmonary disease (COPD) exacerbations. Currently there is no vaccine for RV which is largely due to the existence of ~160 serotypes/strains. We demonstrated previously that immunising mice with highly conserved VP4 and VP2 regions of the RV polyprotein (RV-A16 VP0) generated cross-reactive immunity to RV in vivo. The current study investigated and mapped the epitopes of RV-A16 VP0 that are targets for antibodies in serum samples from VP0 immunisation and RV challenge studies in mice. Recombinant capsid proteins, peptide pools and individual peptides spanning the immunogen sequence (RV-A16 VP0) were assessed for IgG binding sites to identify epitopes. We found that peptide pools covering the C-terminus of VP4, the N-terminus of VP2 and the neutralising NIm-II site within VP2 were bound by serum IgG from immunised mice. The NIm-II site peptide pool blocked IgG binding to the immunogen RV-A16 VP0 and individual peptides within the pool binding IgG were further mapped. Thus, we have identified immunodominant epitopes of RV vaccine candidate RV-A16 VP0, noting that strong IgG binding antibodies were observed that target a key neutralising epitope that is highly variable amongst RV serotypes

Challenges in developing a cross-serotype rhinovirus vaccine

A great burden of disease is attributable to human rhinovirus (HRV) infections which are the major cause of the common cold, exacerbations of both asthma and chronic obstructive pulmonary disease (COPD), and are associated with asthma development. Despite this there is currently no vaccine for HRV. The first vaccine studies showed some promise in terms of serotype-specific protection against cold symptoms, but antigenic heterogeneity amongst the >150 HRVs has been regarded as a major barrier to effective vaccine development and has resulted in little progress over 50 years. Here we review those vaccine studies conducted to date, discuss the difficulties posed by antigenic heterogeneity and describe some recent advances in generating cross-reactive antibodies and T cell responses using peptide immunogens

Effect of HAP decomposition on the corrosion behavior of Ti-HAP biocomposites

Ti-HAP biocomposites are gained attention for combining the attractive properties of Ti and hydroxyapatite (HAP). However, the decomposition of HAP at elevated processing temperatures is a major concern since it can lead to structural flaws and may deteriorate the corrosion resistance of Ti. The present study aims to investigate the corrosion behavior of Ti-HAP composite processed by powder metallurgy by performing potentiodynamic polarization and electrochemical impedance spectroscopy in 0.9wt% NaCl solution at body temperature. Results show that the presence of Ti lowers the HAP decomposition temperatures resulting in the formation of HAP-depleted zones acting as electrochemically active sites, decreasing the corrosion resistance.This study was supported by the Foundation for Science andTechnology (FCT), Portugal with the reference projects UID/EEA/04436/2013, EXCL/EMS-TEC/0460/2012, and M-ERA-NET/0001/2015, as well, by FEDER funds through the COMPETE 2020–Programa Operacional Competitividade eInternacionalização (POCI) with the reference project POCI-01-0145-FEDER-006941. The authors would also like toacknowledge Prof. Ana Senos (University of Aveiro) andProf. José Carlos Teixeira (University of Minho) for theprovision of the characterization facilities

Toward personalization of asthma treatment according to trigger factors

Asthma is a severe and chronic disabling disease affecting more than 300 million people worldwide. Although in the past few drugs for the treatment of asthma were available, new treatment options are currently emerging, which appear to be highly effective in certain subgroups of patients. Accordingly, there is a need for biomarkers that allow selection of patients for refined and personalized treatment strategies. Recently, serological chip tests based on microarrayed allergen molecules and peptides derived from the most common rhinovirus strains have been developed, which may discriminate 2 of the most common forms of asthma, that is, allergen- and virus-triggered asthma. In this perspective, we argue that classification of patients with asthma according to these common trigger factors may open new possibilities for personalized management of asthma.Fil: Niespodziana, Katarzyna. Vienna University of Technology; AustriaFil: Borochova, Kristina. Vienna University of Technology; AustriaFil: Pazderova, Petra. Vienna University of Technology; AustriaFil: Schlederer, Thomas. Vienna University of Technology; AustriaFil: Astafyeva, Natalia. Saratov State Medical University; RusiaFil: Baranovskaya, Tatiana. Belarusian Medical Academy of Post Diploma Studies; BielorrusiaFil: Barbouche, Mohamed Ridha. Institut Pasteur de Tunis; TúnezFil: Beltyukov, Evgeny. Ural State Medical University; RusiaFil: Berger, Angelika. Vienna University of Technology; AustriaFil: Borzova, Elena. Russian Medical Academy of Continuous Professional Education; RusiaFil: Bousquet, Jean. MACVIA; Francia. Humboldt-Universität zu Berlin; AlemaniaFil: Bumbacea, Roxana S.. University of Medicine and Pharmacy "Carol Davila"; RumaniaFil: Bychkovskaya, Snezhana. Krasnoyarsk Medical University; RusiaFil: Caraballo, Luis. Universidad de Cartagena; ColombiaFil: Chung, Kian Fan. Imperial College London; Reino Unido. MRC and Asthma UK Centre in Allergic Mechanisms of Asthma; Reino UnidoFil: Custovic, Adnan. Imperial College London; Reino Unido. MRC and Asthma UK Centre in Allergic Mechanisms of Asthma; Reino UnidoFil: Docena, Guillermo H.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Estudios Inmunológicos y Fisiopatológicos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Estudios Inmunológicos y Fisiopatológicos; ArgentinaFil: Eiwegger, Thomas. University Of Toronto. Hospital For Sick Children; CanadáFil: Evsegneeva, Irina. Sechenov First Moscow State Medical University; RusiaFil: Emelyanov, Alexander. North-Western Medical University; RusiaFil: Errhalt, Peter. University Hospital Krems and Karl Landsteiner University of Health Sciences; AustriaFil: Fassakhov, Rustem. Kazan Federal University; RusiaFil: Fayzullina, Rezeda. Bashkir State Medical University; RusiaFil: Fedenko, Elena. NRC Institute of Immunology FMBA of Russia; RusiaFil: Fomina, Daria. Sechenov First Moscow State Medical University; RusiaFil: Gao, Zhongshan. Zhejiang University; ChinaFil: Giavina Bianchi, Pedro. Universidade de Sao Paulo; BrasilFil: Gotua, Maia. David Tvildiani Medical University; GeorgiaFil: Greber Platzer, Susanne. Vienna University of Technology; AustriaFil: Hedlin, Gunilla. Karolinska Huddinge Hospital. Karolinska Institutet; Sueci

Identification of Critical Amino Acids in an Immunodominant IgE Epitope of Pen c 13, a Major Allergen from Penicillium citrinum

Background: Pen c 13, identified as a 33-kDa alkaline serine protease, is a major allergen secreted by Penicillium citrinum. Detailed knowledge about the epitopes responsible for IgE binding would help inform the diagnosis/prognosis of fungal allergy and facilitate the rational design of hypoallergenic candidate vaccines. The goal of the present study was to characterize the IgE epitopes of Pen c 13. Methodology/Principal Findings: Serum samples were collected from 10 patients with mold allergy and positive Pen c 13 skin test results. IgE-binding epitopes on rPen c 13 were mapped using an enzymatic digestion and chemical cleavage method, followed by dot-blotting and mass spectrometry. A B-cell epitope-predicting server and molecular modeling were used to predict the residues most likely involved in IgE binding. Theoretically predicted IgE-binding regions were further confirmed by site-directed mutagenesis assays. At least twelve different IgE-binding epitopes located throughout Pen c 13 were identified. Of these, peptides S16 (A 148 –E 166) and S22 (A 243 –K 274) were recognized by sera from 90 % and 100 % of the patients tested, and were further confirmed by inhibition assays. Peptide S22 was selected for further analysis of IgE-binding ability. The results of serum screening showed that the majority of IgE-binding ability resided in the C-terminus. One Pen c 13 mutant, G270A (T 261 –K 274), exhibited clearly enhanced IgE reactivity, whereas another, K274A, exhibited dramatically reduced IgE reactivity

An update on molecular cat allergens: Fel d 1 and what else? Chapter 1: Fel d 1, the major cat allergen

Background: Cats are the major source of indoor inhalant allergens after house dust mites. The global incidence of cat allergies is rising sharply, posing a major public health problem. Ten cat allergens have been identified. The major allergen responsible for symptoms is Fel d 1, a secretoglobin and not a lipocalin, making the cat a special case among mammals. Main body: Given its clinical predominance, it is essential to have a good knowledge of this allergenic fraction, including its basic structure, to understand the new exciting diagnostic and therapeutic applications currently in development. The recent arrival of the component-resolved diagnosis, which uses molecular allergens, represents a unique opportunity to improve our understanding of the disease. Recombinant Fel d 1 is now available for in vitro diagnosis by the anti-Fel d 1 specific IgE assay. The first part of the review will seek to describe the recent advances related to Fel d 1 in terms of positive diagnosis and assessment of disease severity. In daily practice, anti-Fel d 1 IgE tend to replace those directed against the overall extract but is this attitude justified? We will look at the most recent arguments to try to answer this question. In parallel, a second revolution is taking place thanks to molecular engineering, which has allowed the development of various forms of recombinant Fel d 1 and which seeks to modify the immunomodulatory properties of the molecule and thus the clinical history of the disease via various modalities of anti-Fel d 1-specific immunotherapy. We will endeavor to give a clear and practical overview of all these trends