Titel Deelnemers "Korte inhoud" "Anti-HIV activity and mode of action of naturally occurring peptides interfering with the viral entry process" "Geoffrey Férir" "At the end of 2012, approximately 34 million people, including children, were infected worldwide with the human immunodeficiency virus (HIV), the etiological agent of AIDS (Acquired Immune Deficiency Syndrome). Sub-Saharan Africa is the most severly affected region. Especially women are highly susceptible to HIV infection, based on socio-economical and cultural aspects such as religion, polygamy, poverty, rape and war. The transmission rate of HIV infection increases significantly in combination with other genital diseases like bacterial vaginosis, syphilis or genital ulcers caused by herpes simplex virus type 2 (HSV-2) infections. According to UNAIDS, the number of new HIV infections is declining in Sub-Saharan Africa, while the opposite is true in other parts of the world such as Eastern Europe, Middle East and Central Asia. The huge worldwide diversity of HIV subtypes (e.g. the presence of subtype B in Europe and the US and subtype C in Africa) makes it very difficult to develop an effective vaccine. However, the presence of a wide variety of antiretroviral drugs, used in combination therapy, switches HIV from a lethal disease into a chronic disorder. At present, none of the current anti-HIV drugs can eradicate the virus, making HIV treatment a lifelong commitment. Therefore it is necessary to generate also effective prevention campaigns to make people aware of the risks and lifelong consequences of HIV/AIDS infections. These prevention methods in combination with effective treatment options are a crucial step in trying to decrease the number of novel HIV infections. The search for an effective microbicide has been ongoing for more than a decade in order to reduce the sexual transmission of HIV. Microbicides are tools (e.g. vaginal/rectal gels, films, suppositories or intravaginal ring devices) that women, and even (homosexual) men, can use without the knowledge of their partners or other persons. As various clinical trials using broad-spectrum aspecific microbicides (e.g. spermicides, detergents) failed, microbicidal research has focused more on specific antiviral compounds, which act a crucial steps (e.g. reverse transcriptase) in the replication cycle of HIV. This led to a proof-of-concept, whereby a 1% vaginal tenofovir gel, applied within 24 h before and after coitus, reduced the sexual transmission of HIV-1 and HSV-2 in women with, respectively, 39% and 51%. HIV particles have highly glycosylated structures at the surfaces, which are considered as a target for a novel class of antiviral compounds, the carbohydrate-binding agents (or CBAs). Various members of the CBAs were reported to be potential microbicidal candidates. As for the treatment of HIV/AIDS infections, an effective microbicide shall also presumably consist of a combination of at least two different products. Oral tenofovir, the most prescribed anti-HIV drug for the treatment of HIV/AIDS infections, was mid 2012 also approved by the US FDA in combination with emtricitabine as Truvada(R) for pre-exposure prophylaxis (PrEP) against HIV infections and transmission. Inour research, we showed that tenofovir can be combined with various members of the class of CBAs (e.g. HHA, GNA, MVN, BanLec,...) and that this synergy increases their combined antiviral potency and decreases potential cytotoxicity of these agents (Chapter 3).Despite the fact that the glycans present on gp120 are an attractive target for antiviral therapy, there is a huge diversity between the HIV subtypes as such. We specifically investigated the subtypes B and C, as they account for >60% of the total HIV-1 infections worldwide. In a follow-up study, we investigated if griffithsin (GRFT), the most potent anti-HIV-1 CBA described to date, could be combined with other classes of antiretroviral drugs (e.g. integrase inhibitors, entry inhibitors and reverse transcriptase inhibitors) and if there is a complete loss of antiviral activity when certain sugars differ between the included subtypes. It was reported that the N-linked glycans N295 and N234 on gp120 were involved in the interaction with GRFT and we focused mainly on these two glycans in our experiments. We observed that GRFT lost only minor activity when one or even both sugars were absent. Moreover, GRFT showed synergy with the HIV-1 inhibitors maraviroc (CCR5 antagonist), enfuvirtide (gp41 fusion peptide inhibitor), raltegravir (integrase inhibitor) and tenofovir (reverse transcriptase inhibitor) (Chapter 4). Each CBA binds to specific sugar moieties (e.g. mannose or N-aceylglucosamine) and their bridges (e.g. alpha(1,6) or alpha(1,2) linkages). Based on the above mentioned results, we investigated if CBAs as such could be combined against wild type HIV-1 and HIV-2 strains, and also against certain HIV-1 CBAresistant strains (Chapter 5). We performed most of the experiments with GRFT. First, we could prove that GRFT and the banana lectin (BanLec) also possess an equally potent anti-HIV-2 activity. Various (pre-)clinical antiretroviral agents have a strong reduced, if any, antiviral activity against HIV-2 (e.g. enfuvirtide, microvirin (MVN)). We could also demonstrate that GRFT, in combination with various CBAs (such as MVN, BanLec or the broad neutralizing anti-carbohydrate-binding mAb 2G12) inhibited HIV replication more efficiently. Surprisingly, when the CBAs HHA and GNA were combined, rather antagonistic to additive effects were observed against wild type HIV viruses and synergy against CBAresistant HIV-1 strains, which deleted 1 (as seen with HIV-1 NL4.32G12mAbres. virus) to 4 N-linked glycans (in case of HIV-1 NL4.3MVNres. virus). In addition, GRFT and BanLec kept their potent antiviral activity against these two CBAresistant viruses. These results clearly indicate that (i) CBAs could be combined as such, (ii) that they exhibit different binding patterns on the glycans of gp120 and that (iii) affinity and kinetics are crucial factors in their antiviral activity.Semen and cervicovaginal secretions of HIV-infected persons contain cell-free HIV particles and HIV-infected immune cells (e.g. T cells and macrophages). These cells can easily transmit HIV through T cell - T cell contacts to uninfected CD4+ uninfected T cells. The dendritic cells (DCs) are a population of cells, which detect and capture HIV particles upon infection. These cells express DC-SIGN (dendritic cell-specific intercellular adhesion molecule-3 grabbing non-integrin), an attachment receptor for various pathogens such as HIV. Upon receptor interaction the virus is efficiently transmitted to the non-infected CD4+ T cells in the lymph nodes. So, we investigated in more detail if GRFT could also inhibit, alone and in combination with other classes of antiretroviral drugs (namely entry inhibitors, reverse transcriptase inhibitors, integrase inhibitors and protease inhibitors), the HIV-1 transmission/replication and the CD4+ target T cell destruction as well, through these T cell - T cell and DCs - T cell contacts (Chapter 6). These intercellular contacts result in the formation of multinucleated giant cells or syncytia. We were able to visualize how these giant cells were formed in function of time by the JuLI(TM) live cell-imaging viewer and how the CD4+ target T cell population was destroyed. These data also clearly show that GRFT, alone and in combination, prevents both cell-to-cell HIV-1 transmission and destruction of the CD4+ T cell population.In the second part of this thesis, we focused more on the novel antibiotic peptides feglymycin (FGM) and labyrinthopeptins (LabyA1). We investigated more in depth their antiviral spectrum and mechanism of action. FGM, a peptide of 13 amino acids, showed a consistent broad-spectrum anti-HIV activity in inhibiting infection with cell-free HIV particles as well as in cocultivation assays between persistently HIV-infected T cells and CD4+ non-infected T cells. In the DC-SIGN dependent transmission route FGM inhibits not the capture of the virus on DC-SIGN, but subsequently the viral replication upon cocultivation with the CD4+ target T cells. These data clearly indicate that the glycans present on gp120 are not involved in the anti-HIV mechanism of action of FGM. By the use of various virus binding assays (e.g. surface plasmon resonance, ELISAs, flow cytometry) and viral replication studies, we were able to prove that FGM inhibited the CD4/gp120 binding, through interaction with the viral envelope protein gp120. Alanine scanning mutagenesis studies of FGM, where each amino acid is systematically replaced by a neutral alanine, resulted in a significant loss of antiviral activity and affinity for gp120, when the L-aspartate at position 13 was replaced by a neutral alanine. Cultivating HIV-1 in the presence of increasing concentrations of FGM, generated a resistant HIV-1 strain (IIIBFGMres. virus), with two unique mutations in gp120, namely I153L in the V2 loop and K457I in the C5 region. These two mutations are in the neighbourhood of regions in gp120 involved in the cellular CD4 receptor binding. In addition, our HIV-1 IIIBFGMres. virus showed cross-resistance with the two well-known compounds dextran sulfate and cyclotriazadisulfonamide (CADA), which, respectively, interfere directly and indirectly with the CD4/gp120 interaction (Chapter 7).Likewise, we investigated the antiviral activity of the labyrinthopeptins, that belong to a novel class of lantibiotics (lanthionine-containing antibiotics) (Chapter 8). The most well-known, and so far commercially used, lantibiotic is nisin in the food industry. As far as we know LabyA1 and LabyA2 are the only two described labyrinthopeptins and preliminary data reported a moderate anti-herpes activity in vitro. Based in these results, we investigated these peptides for their anti-HIV activity, as there is more and more evidence that HIV-1 and HSV-2 are important co-pathogens that synergistically cause various diseases. In several cell lines and against various wild type and drug resistant HIV and HSV strains LabyA1 showed a consistent broad-spectrum antiviral activity. LabyA2 demonstrated no anti-HIV activity and a weak anti-HSV activity. Nisin, used as reference lantibiotic, was not able to inhibit any of the evaluated viruses. As described for GRFT and FGM, LabyA1 inhibits also the DC-SIGN mediated route of transmission and fusion between persistently HIV-infected T cells and non-infected CD4+ target T cells. Virus binding and replication experiments demonstrated that LabyA1 interfered with the entry process of HIV-1 and HSV-2. Additional studies showed an interaction of LabyA1 with the surface glycoprotein gp120 and blocked in this way viral entry in a post-CD4 binding event. As HIV-1 and HSV-2 are two co-pathogens, increasing each others infection, LabyA1 could have potential as a microbicidal agent applied for example in a vaginal gel. Therefore, it is necessary to evaluate the safety of LabyA1 on epithelial cells, as in previous clinical trials an increase in HIV transmission was noted due to vaginal epithelial cell toxicity of potential microbicidal candidates (e.g. nonoxynol-9). A microbicide should not harm the epithelial integrity, causing neither inflammation nor stimulation of the viral target cells. When PBMCs were pretreated with LabyA1, in contrast to the mitogenic lectin phytohemagglutinin (PHA), no increase in the expression of the cellular activation markers CD69 and CD25 was seen, nor increased HIV, nor significant induction of various inflammatory cytokines and chemokines. The vaginal bacterial flora forms a natural barrier against various pathogenic intruders by creating an acidic environment. As natural pH-values in the vagina can increase the risk for HIV transmission, it is therefore very important that an effective potential microbicide causes no harm to the vaginal flora. As LabyA1 is an antibiotic peptide, we investigated its effect on the growth of various vaginal Lactobacilli strains and compared it with nisin. These data clearly demonstrate that LabyA1 caused no toxicity in these vaginal Lactobacilli at concentrations up to 120 µM, while nisin killed most of the these Lactobacilli at relatively low concentrations (at 3 µM). This also clearly indicates the discrepancy between the antiviral and antibacterial activity of different members of the class of lantibiotics. Due to its dual antiviral activity, which is highly consistent against both HIV and HSV (in contrast to tenofovir, showing a strongly reduced antiviral activity against HSV-2, compared to HIV-1). LabyA1 can be seen as a potential microbicidal candidate. As microbicides may comprise at least two active agents, we investigated the degree of synergy with other widely clinically used anti-HIV (e.g. tenofovir, raltegravir, saquinavir) and anti-HSV (e.g. acyclovir) drugs. These studies demonstrated no antagonistic drug combinations, increasing again its potential for further microbicidal development.These data clearly show the need to search for an effective microbicide. The class of CBAs could be combined with other antiviral agents which are clinically-approved or under development. The labyrinthopeptins, especially LabyA1, can be seen as a lead peptide for the development of novel and even more potent derivatives with anti-HIV and anti-HSV activity; while novel derivatives of FGM could lead to a new class of small peptidic CD4/gp120 inhibitors." "4th Pediatric Allergy and Asthma Meeting (PAAM)" "Dominique Bullens" "Table of contents WORKSHOP 4: Challenging clinical scenarios (CS01–CS06) CS01 Bullous lesions in two children: solitary mastocytoma S. Tolga Yavuz, Ozan Koc, Ali Gungor, Faysal Gok CS02 Multi-System Allergy (MSA) of cystic fibrosis: our institutional experience Jessica Hawley, Christopher O’Brien, Matthew Thomas, Malcolm Brodlie, Louise Michaelis CS03 Cold urticaria in pediatric age: an invisible cause for severe reactions Inês Mota, Ângela Gaspar, Susana Piedade, Graça Sampaio, José Geraldo Dias, Miguel Paiva, Mário Morais-Almeida CS04 Angioedema with C1 inhibitor deficiency in a girl: a challenge diagnosis Cristina Madureira, Tânia Lopes, Susana Lopes, Filipa Almeida, Alexandra Sequeira, Fernanda Carvalho, José Oliveira CS05 A child with unusual multiple organ allergy disease: what is the primer? Fabienne Gay-Crosier CS06 A case of uncontrolled asthma in a 6-year-old patient Ioana-Valentina Nenciu, Andreia Florina Nita, Alexandru Ulmeanu, Dumitru Oraseanu, Carmen Zapucioiu ORAL ABSTRACT SESSION 1: Food allergy (OP01–OP06) OP01 Food protein-induced enterocolitis syndrome: oral food challenge outcomes for tolerance evaluation in a Pediatric Hospital Adrianna Machinena, Olga Domínguez Sánchez, Montserrat Alvaro Lozano, Rosa Jimenez Feijoo, Jaime Lozano Blasco, Mònica Piquer Gibert, Mª Teresa Giner Muñoz, Marcia Dias da Costa, Ana Maria Plaza Martín OP02 Characteristics of infants with food protein-induced enterocolitis syndrome and allergic proctocolitis Ebru Arik Yilmaz, Özlem Cavkaytar, Betul Buyuktiryaki, Ozge Soyer, Cansin Sackesen OP03 The clinical and immunological outcomes after consumption of baked egg by 1–5 year old egg allergic children: results of a randomised controlled trial MerrynNetting, Adaweyah El-Merhibi, Michael Gold, PatrickQuinn, IrmeliPenttila, Maria Makrides OP04 Oral immunotherapy for treatment of egg allergy using low allergenic, hydrolysed egg Stavroula Giavi, Antonella Muraro, Roger Lauener, Annick Mercenier, Eugen Bersuch, Isabella M. Montagner, Maria Passioti, Nicolò Celegato, Selina Summermatter, Sophie Nutten, Tristan Bourdeau, Yvonne M. Vissers, Nikolaos G. Papadopoulos OP05 Chemical modification of a peanut extract results in an increased safety profile while maintaining efficacy Hanneke van der Kleij, Hans Warmenhoven, Ronald van Ree, Raymond Pieters, Dirk Jan Opstelten, Hans van Schijndel, Joost Smit OP06 Administration of the yellow fever vaccine in egg allergic children Roisin Fitzsimons, Victoria Timms, George Du Toit ORAL ABSTRACT SESSION 2: Asthma (OP07–OP12) OP07 Previous exacerbation is the most important risk factor for future exacerbations in school-age children with asthma S. Tolga Yavuz, Guven Kaya, Mustafa Gulec, Mehmet Saldir, Osman Sener, Faysal Gok OP08 Comparative study of degree of severity and laboratory changes between asthmatic children using different acupuncture modalities Nagwa Hassan, Hala Shaaban, Hazem El-Hariri, Ahmed Kamel Inas E. Mahfouz OP09 The concentration of exhaled carbon monoxide in asthmatic children with different controlled stadium Papp Gabor, Biro Gabor, Kovacs Csaba OP10 Effect of vitamin D3 supplementation during pregnancy on risk of persistent wheeze in the offspring: a randomised clinical trial Bo Chawes, Klaus Bønnelykke, Jakob Stokholm, Lene Heickendorff, Susanne Brix, Morten Rasmussen, Hans Bisgaard OP11 Lung function development in childhood Henrik Wegener Hallas, Bo Chawes, Lambang Arianto, Hans Bisgaard OP12 Is the effect of maternal and paternal asthma different in female and male children before puberty? Maike Pincus, Thomas Keil, Andreas Reich, Ulrich Wahn, Susanne Lau, Linus Grabenhenrich ORAL ABSTRACT SESSION 3: Epidemiology—genetics (OP13–OP18) OP13 Lifestyle is associated with incidence and category of allergen sensitisation: the ALADDIN birth cohort Sara Fagerstedt, Helena Marell Hesla, Emelie Johansson, Helen Rosenlund, Axel Mie, Annika Scheynius, Johan Alm OP15 Maternal filaggrin mutations increase the risk of atopic dermatitis in children: an effect independent of mutation inheritance Jorge Esparza-Gordillo, Anja Matanovic, Ingo Marenholz, Anja Bauerfeind, Klaus Rohde, Katja Nemat, Min-Ae Lee-Kirsch, Magnus Nordenskjöld, Marten C. G. Winge, Thomas Keil, Renate Krüger, Susanne Lau, Kirsten Beyer, Birgit Kalb, Bodo Niggemann, Norbert Hübner, Heather J. Cordell, Maria Bradley, Young-Ae Lee OP16 Allergic multimorbidity of asthma, rhinitis and eczema in the first 2 decades of the German MAS birth cohort Thomas Keil, Hannah Gough, Linus Grabenhenrich, Dirk Schramm, Andreas Reich, John Beschorner, Antje Schuster, Carl-Peter Bauer, Johannes Forster, Fred Zepp, Young-Ae Lee, Renate Bergmann, Karl Bergmann, Ulrich Wahn, Susanne Lau OP17 Childhood anaphylaxis: a growing concern Filipe Benito Garcia, Inês Mota, Susana Piedade, Ângela Gaspar, Natacha Santos, Helena Pité, Mário Morais-Almeida OP18 Indoor exposure to molds and dampness in infancy and its association to persistent atopic dermatitis in school age. Results from the Greek ISAAC II study Athina Papadopoulou, Despina Mermiri, Elpida Xatziagorou, Ioannis Tsanakas, Stavroula Lampidi, Kostas Priftis ORAL ABSTRACT SESSION 4: Pediatric rhinitis—immunotherapy (OP19–OP24) OP19 Associations between residential greenness and childhood allergic rhinitis and aeroallergen sensitisation in seven birth cohorts Elaine Fuertes, Iana Markevych, Gayan Bowatte, Olena Gruzieva, Ulrike Gehring, Allan Becker, Dietrich Berdel, Michael Brauer, Chris Carlsten, Barbara Hoffmann, Anita Kozyrskyj, Caroline Lodge, Göran Pershagen, Alet Wijga, Heinrich Joachim OP20 Full symptom control in pediatric patients with allergic rhinitis and asthma: results of a 2-year sublingual allergen immunotherapy study Zorica Zivkovic, Ivana Djuric-Filipovic, Jasmina Jocić-Stevanovic, Snežana Zivanovic OP21 Nasal epithelium of different ages of atopic subjects present increased levels of oxidative stress and increased cell cytotoxicity upon rhinovirus infection Styliani Taka, Dimitra Kokkinou, Aliki Papakonstantinou, Panagiota Stefanopoulou, Anastasia Georgountzou, Paraskevi Maggina, Sofia Stamataki, Vassiliki Papaevanggelou, Evangelos Andreakos, Nikolaos G. Papadopoulos OP22 Cluster subcutaneous immunotherapy schedule: tolerability profile in children Monica Piquer Gibert, Montserrat Alvaro Lozano, Jaime Lozano Blasco, Olga Domínguez Sánchez, Rosa Jiménez Feijoo, Marcia Dias da Costa, Mª Teresa Giner Muñoz, Adriana Machinena Spera, Ana Maria Plaza Martín OP23 Rhinitis as a risk factor for asthma severity in 11-year old children: population-based cohort study Matea Deliu, Danielle Belgrave, Angela Simpson, Adnan Custovic OP24 The Global Lung Function Initiative equations in airway obstruction evaluation of asthmatic children João Gaspar Marques, Pedro Carreiro-Martins, Joana Belo, Sara Serranho, Isabel Peralta, Nuno Neuparth, Paula Leiria-Pinto POSTER DISCUSSION SESSION 1: Food allergy (PD01–PD05) PD01 Allergen-specific humoral and cellular responses in children who fail egg oral immunotherapy due to allergic reactions Marta Vazquez-Ortiz, Mariona Pascal, Ana Maria Plaza, Manel Juan PD02 FoxP3 epigenetic features in children with cow milk allergy Lorella Paparo, Rita Nocerino, Rosita Aitoro, Ilaria Langella, Antonio Amoroso, Alessia Amoroso, Carmen Di Scala, Roberto Berni Canani PD04 Combined milk and egg allergy in early childhood: let them eat cake? Santanu Maity, Giuseppina Rotiroti, Minal Gandhi PD05 Introduction of complementary foods in relation to allergy and gut microbiota in farm and non-farm children Karin Jonsson, Annika Ljung, Bill Hesselmar, Ingegerd Adlerbert, Hilde Brekke, Susanne Johansen, Agnes Wold, Ann-Sofie Sandberg POSTER DISCUSSION SESSION 2: Asthma and wheeze (PD06–PD16) PD06 The association between asthma and exhaled nitric oxide is influenced by genetics and sensitisation Björn Nordlund, Cecilia Lundholm, Villhelmina Ullemar, Marianne van Hage, Anne Örtqvist, Catarina Almqvist PD09 Prevalence patterns of infant wheeze across Europe Anna Selby, Kate Grimshaw, Thomas Keil, Linus Grabenhenrich, Michael Clausen, Ruta Dubakiene, Alessandro Fiocchi, Marek Kowalski, Nikos Papadopoulos, Marta Reche, Sigurveig Sigurdardottir, Aline Sprikkleman, Paraskevi Xepapadaki, Clare Mills, Kirsten Beyer, Graham Roberts PD10 Epidemiologic changes in recurrent wheezing infants Herberto Jose Chong Neto, Gustavo Falbo Wandalsen, Ana Carolina Dela Bianca, Carolina Aranda, Nelson Augusto Rosário, Dirceu Solé, Javier Mallol, Luis García Marcos PD13 A single nucleotide polymorphism in the GLCCI1 gene is associated with response to asthma treatment in children IvanaBanic, Matija Rijavec, Davor Plavec, Peter Korosec, Mirjana Turkalj PD14 Pollen induced asthma: Could small molecules in pollen exacerbate the protein-mediated allergic response? Alen Bozicevic, Maria De Mieri, Matthias Hamburger PD15 A qualitative study to understand how we can empower teenagers to better self-manage their asthma Simone Holley, Ruth Morris, Frances Mitchell, Rebecca Knibb, Susan Latter, Christina Liossi, Graham Roberts PD16 Polymorphism of endothelial nitric oxide synthase (eNOS) gene among Egyptian children with bronchial asthma Mostafa M. M. Hassan POSTER DISCUSSION SESSION 3: Mechanisms—Epidemiology (PD17–PD21) PD17 Pregnancy outcomes in relation to development of allergy in a Swedish birth cohort Malin Barman, Anna Sandin, Agnes Wold, Ann-Sofie Sandberg PD18 Evolution of the IgE response to house dust mite molecules in childhood Daniela Posa, Serena Perna, Carl-Peter Bauer, Ute Hoffmann, Johannes Forster, Fred Zepp, Antje Schuster, Ulrich Wahn, Thomas Keil, Susanne Lau, Kuan-Wei Chen, Yvonne Resch, Susanne Vrtala, Rudolf Valenta, Paolo Maria Matricardi PD19 Antibody recognition of nsLTP-molecules as antigens but not as allergens in the German-MAS birth cohort Olympia Tsilochristou, Alexander Rohrbach, Antonio Cappella, Stephanie Hofmaier, Laura Hatzler, Carl-Peter Bauer, Ute Hoffmann, Johannes Forster, Fred Zepp, Antje Schuster, RaffaeleD’Amelio, Ulrich Wahn, Thomas Keil, Susanne Lau, Paolo Maria Matricardi PD20 Early life colonization with Lactobacilli and Staphylococcus aureus oppositely associates with the maturation and activation of FOXP3+ CD4 T-cells Sophia Björkander, Maria A. Johansson, Gintare Lasaviciute, Eva Sverremark-Ekström PD21 Genome-wide meta-analysis identifies 7 susceptibility loci involved in the atopic march Ingo Marenholz, Jorge Esparza-Gordillo, Franz Rüschendorf, Anja Bauerfeind, David P. Strachan, Ben D. Spycher, Hansjörg Baurecht, Patricia Margaritte-Jeannin, Annika Sääf, Marjan Kerkhof, Markus Ege, Svetlana Baltic, Melanie C Matheson, Jin Li, Sven Michel, Wei Q. Ang, Wendy McArdle, Andreas Arnold, Georg Homuth, Florence Demenais, Emmanuelle Bouzigon, Cilla Söderhäll, Göran Pershagen, Johan C. de Jongste, Dirkje S Postma, Charlotte Braun-Fahrländer, Elisabeth Horak, Ludmila M. Ogorodova, Valery P. Puzyrev, Elena Yu Bragina, Thomas J Hudson, Charles Morin, David L Duffy, Guy B Marks, Colin F Robertson, Grant W Montgomery, Bill Musk, Philip J Thompson, Nicholas G. Martin, Alan James, Patrick Sleiman, Elina Toskala, Elke Rodriguez, Regina Fölster-Holst, Andre Franke, Wolfgang Lieb, Christian Gieger, Andrea Heinzmann, Ernst Rietschel, Thomas Keil, Sven Cichon, Markus M Nöthen, Craig E Pennell, Peter D Sly, Carsten O Schmidt, Anja Matanovic, Valentin Schneider, Matthias Heinig, Norbert Hübner, Patrick G. Holt, Susanne Lau, Michael Kabesch, Stefan Weidinger, Hakon Hakonarson, Manuel AR Ferreira, Catherine Laprise, Maxim B. Freidin, Jon Genuneit, Gerard H Koppelman, Erik Melén, Marie-Hélène Dizier, A. John Henderson, Young Ae Lee POSTER DISCUSSION SESSION 4: Food allergy—Anaphylaxis (PD22–PD26) PD22 Atopy patch test in food protein induced enterocolitis caused by solid food Purificacion González-Delgado, Esther Caparrós, Fernando Clemente, Begoña Cueva, Victoria M. Moreno, Jose Luis Carretero, Javier Fernández PD23 Watermelon allergy: a novel presentation Kate Swan, George Du Toit PD24 A pilot study evaluating the usefulness of a guideline template for managing milk allergy in primary care Mudiyur Gopi, Tim Smith, Edara Ramesh, Arun Sadasivam PD26 Efficacy and safety of cow’s milk oral immunotherapy protocol Inês Mota, Filipe Benito Garcia, Susana Piedade, Angela Gaspar, Graça Sampaio, Cristina Arêde, Luís Miguel Borrego, Graça Pires, Cristina Santa-Marta, Mário Morais-Almeida POSTER DISCUSSION SESSION 5: Prevention and treatment—Allergy (PD27–PD36) PD27 Allergy-protection by the lactic acid bacterium Lactococcus lactis G121: mode-of-action as revealed in a murine model of experimental allergy Stephanie Brand, Karina Stein, Holger Heine, Marion Kauth PD29 The relationship between quality of life and morning salivary cortisol after acute bronchiolitis in infancy Leif Bjarte Rolfsjord, Egil Bakkeheim, Johan Alm, Håvard Ove Skjerven, Kai-Håkon Carlsen, Jon Olav Hunderi, Teresa Løvold Berents, Petter Mowinckel, Karin C. Lødrup Carlsen PD30 Randomised trial of the efficacy of MP29-02* compared with fluticasone propionate nasal spray in children aged ≥6 years to" "Regulation of seed germination by diurnally alternating temperatures in disturbance-adapted banana crop wild relatives (Musa acuminata)" "Simon Kallow, R Davies, Bart Panis, Steven B. Janssens, Filip Vandelook, Arne Mertens, Rony Swennen, MB Tahir, John Dickie" "Seed conservation of banana crop wild relatives (Musa L. spp.) is limited because of lack of knowledge about their germination ecology. Musa acuminata Colla, the most important banana crop wild relative, is distributed in tropical and subtropical Asian and Pacific rainforests and colonizes disturbed sites. The role of temperature in stimulating/inhibiting germination to detect disturbance when canopy gaps are formed is not well known. We assessed seed germination thermal requirements of three subspecies of M. acuminata using nine seed accessions which had been stored in the Millennium Seed Bank. Diurnally alternating temperature cycles were almost completely essential for germination compared with constant temperatures. Germination was optimal when the upper temperature of a diurnal cycle was at 35 degrees C; the lower temperature of the cycle was less important. Subspecies occurrence coordinates were used to extract climate temperature data which were then compared against the temperature requirements for germination from our experiment results. Maximum temperatures of the warmest month across subspecies ranges were close to but below optimal germination temperatures, as were diurnal ranges, suggesting soil-warming at the micro-climate level following gap creation is important for M. acuminata seed germination. Additionally, pre-treatment for 3 months at 60% relative humidity at constant 25 degrees C improved germination from 14 +/- 10 (mean, standard deviation) to 41 +/- 29% suggesting a period in the soil seed bank under the canopy may increase sensitivity to alternating temperature cycles. Overall viability was low (49 +/- 28%), and considerable variance was caused by the different accessions. Germination remained somewhat inconsistent." "Identification of resistant sources to a virulent Fusarium wilt strain (VCG 0124) infecting Cavendish bananas" "Rony Swennen" "Bananas are vital for food security in many countries, and half of banana production relies solely on ‘Cavendish’ (AAA), which is presently threatened by the fungal pathogen Fusarium oxysporum f. sp. cubense (Foc) tropical race 4. This particular virulent Foc strain was also found to attack other banana varieties of commercial importance. As there is no single effective management practice available so far, this study was undertaken to determine resistant sources from the genotype collection available at the ICAR-National Research Centre for Banana, Tiruchirappalli, Tamil Nadu, India for direct use by farmers and/or in breeding programmes to develop resistant hybrids. A total of 258 genotypes of different ploidies and genomic constitutions were tested against Foc race 1 (VCG 0124). In total, 19 genotypes (AA Unique-6, BB type-2, AAA Unique-1, AAA Cavendish-1, AAB Mysore-3, AAB Pome-1, AAB Plantain-4 and AAAB-1) were found to be immune; eight genotypes (AA Unique-1, BB type-3, AAA Cavendish-1, AAB Mysore-1, AAB Unique-1, AAB Plantain-1) were highly resistant; and nine genotypes (AA Unique-1, AAA Cavendish-3, AAB Silk-1, AAB Pome-4) were resistant. The genotypes that are resistant to the virulent Foc race 1 (VCG 0124) strain can be exploited directly for commercialization and/or in breeding programs to develop resistant hybrids." "Maximizing genetic representation in seed collections from populations of self and cross-pollinated banana wild relatives" "Simon Kallow, Bart Panis, Dang Toan Vu, TD Vu, J Paofa, Arne Mertens, Rony Swennen, Steven B. Janssens" "Background Conservation of plant genetic resources, including the wild relatives of crops, plays an important and well recognised role in addressing some of the key challenges faced by humanity and the planet including ending hunger and biodiversity loss. However, the genetic diversity and representativeness of ex situ collections, especially that contained in seed collections, is often unknown. This limits meaningful assessments against conservation targets, impairs targeting of future collecting and limits their use. We assessed genetic representation of seed collections compared to source populations for three wild relatives of bananas and plantains. Focal species and sampling regions were M. acuminata subsp. banksii (Papua New Guinea), M. balbisiana (Viet Nam) and M. maclayi s.l. (Bougainville, Papua New Guinea). We sequenced 445 samples using suites of 16-20 existing and newly developed taxon-specific polymorphic microsatellite markers. Samples of each species were from five populations in a region; 15 leaf samples from different individuals and 16 seed samples from one infructescence ('bunch') were analysed for each population. Results Allelic richness of seeds compared to populations was 51, 81 and 93% (M. acuminata, M. balbisiana and M. maclayi respectively). Seed samples represented all common alleles in populations but omitted some rarer alleles. The number of collections required to achieve the 70% target of the Global Strategy for Plant Conservation was species dependent, relating to mating systems. Musa acuminata populations had low heterozygosity and diversity, indicating self-fertilization; many bunches were needed (> 15) to represent regional alleles to 70%; over 90% of the alleles from a bunch are included in only two seeds. Musa maclayi was characteristically cross-fertilizing; only three bunches were needed to represent regional alleles; within a bunch, 16 seeds represent alleles. Musa balbisiana, considered cross-fertilized, had low genetic diversity; seeds of four bunches are needed to represent regional alleles; only two seeds represent alleles in a bunch. Conclusions We demonstrate empirical measurement of representation of genetic material in seeds collections in ex situ conservation towards conservation targets. Species mating systems profoundly affected genetic representation in seed collections and therefore should be a primary consideration to maximize genetic representation. Results are applicable to sampling strategies for other wild species." "AMF-induced biocontrol against plant parasitic nematodes in Musa sp.: a localized or systemic effect" "Annemie Elsen, Rony Swennen, Dirk De Waele" "Although mycorrhizal colonization provides a bioprotectional effect against a broad range of soil-borne pathogens, including plant parasitic nematodes, the commercial use of arbuscular mycorrhizal fungi (AMF) as biocontrol agents is still in its infancy. One of the main reasons is the poor understanding of the modes of action. Most AMF mode of action studies focused on AMF-bacterial/fungal pathogens. Only few studies so far examined AMF-plant parasitic nematode interactions. Therefore, the aim of the study was to determine whether the AMF Glomus intraradices was able to incite systemic resistance in banana plants towards Radopholus similis and Pratylenchus coffeae, two plant parasitic nematodes using a split-root compartmental set-up. The AMF reduced both nematode species by more than 50%, even when the AMF and the plant parasitic nematodes were spatially separated. The results obtained demonstrate for the first time that AMF have the ability to induce systemic resistance against plant parasitic nematodes in a root system." "Impact of insecticide and pollinator-enhancing substrate applications on cocoa (Theobroma cacao) cherelle and pod production in Cote d'Ivoire" "Wouter Vanhove, Raymond Karlhis Yao, Jean-Claude N'zi, Luc Affoli N'Guessan Toussaint, Alexandre Kaminski, Guy Smagghe, Patrick Van Damme" "Cocoa yield in the major cocoa-producing countries is far below potential levels. It has been shown that apart from poor soil fertility, inadequate genotypes and pest and disease incidence, this yield gap is caused by below-optimum pollination levels. On 3 Ivorian cocoa farms, during the six months preceding the main harvest season of 2018-2019 (August 2018 until January 2019), we used generalized mixed models to investigate how the creation of a pollinator-friendly environment by applying rotting organic material (banana pseudostems) to cocoa fields, combined with and without insecticide applications, influences cocoa production. It was found that banana pseudostem treatments had a positive effect on cherelle production but that this effect was only observed in plots treated with insecticide to protect cherelles against sap-sucking mirids, at the beginning of the experiment. Furthermore, although we did not find significant differences in cherelle wilt rates between treated and control plots, we did not observe a significantly higher accumulated number of mature pods that were produced on trees treated with substrate and untreated control trees during the 25 week experimental period. The pollination-enhancing effect of the substrate on cherelle production in sprayed plots was significantly higher in trees that were close ( < 1 m) to the holes to which the substrate was applied, compared to trees that were further away from these holes. Reduced rainfall towards the end of the minor rainy season of October - November, concurred with a decrease in the number of flowers but also with a decrease in fruit set rate. Soils of all experimental farms had nutrient levels considered to be inadequate for cocoa production, which can explain why the increase in cherelles ( + 75 % and + 50 % in trees respectively close to and further away from substrate holes) did not result in significant increases in mature pods. Our results suggest that closing the pollination gap will close the cocoa yield gap, only when other factors that prevent cherelles to develop into mature pods, are addressed." "Incidence de la chenille légionnaire d’automne (Spodoptera frugiperda JE Smith) et niveau de connaissance de ce ravageur par les agriculteurs de Kisangani et ses environs, RD Congo" "Louis LOOLI BOYOMBE, Elie NGUO, François Malaisse, Jean Claude MONZENGA" "The fall armyworm (Spodoptera frugiperda J.E. Smith) poses a serious threat to farmers in Africa, and moreresearch is urgently needed to help farmers to manage this pest effectively. The objective of this study was to assess theincidence and severity of the damage of the fall armyworm on the corn crop and at the same time to assess the level ofknowledge and management of this pest by farmers of the Kisangani region and its surroundings. In the fields evaluated onthe Kisangani-Buta road axis, the attack rate is between 64.5 - 75.5% for a severity of level 7, the pure corn fields were moreattacked than the associated corn fields mainly with cassava, peanuts, banana and rice. Its appearance has been reported since2016 but the majority of farmers on this axis have it more observed from 2017 and 2018. The majority of them confirm thatthe damage is severe and that they are concerned about it. Faced with these attacks, some farmers do not know what to do tofight against this pest, others on the other hand try to protect their crops by spreading ashes or certain antibiotics on plants orsimply mechanical destruction of the eggs and larvae of this pest." "Protein-mediated killing among bacteria: structure and function of prokaryotic MMBL lectins" "Maarten Ghequire" "Production of bacteriocins represents a highly diversified defense mechanism, identified in virtually all lineages of bacteria. These proteinaceous toxins are specifically directed against related bacteria and their production confers to a eco-evolutionary advantage for the producing organism. In this work, the objective was to further investigate the LlpA family of lectin-like bacteriocins, originally identified in the banana rhizosphere isolate P. putida BW11M1.The solved crystal structure of LlpA, the prototype lectin-like bacteriocin, unequivocally assigned this protein to the class of the so-called monocot mannose-binding lectin (MMBL) proteins, also designated B-lectins. LlpA is built from two tightly interacting ß-prism-folded MMBL modules, stabilized by a C-terminal ß-hairpin extension. The MMBL modules of LlpA display pseudo-threefold symmetry, domain stabilization by a central tryptophan triad, and a ß-strand swap interconnecting these two domains, hallmarks of B-lectins. Each MMBL domain contains three putative mannose-binding motifs exhibiting different levels of sequence degeneracy. Of these six sites, only three retain their potential carbohydrate-binding capacity. Binding of methyl-D-alfa-mannopyranoside and oligomannosides could only be demonstrated for one of these sites, located in the C-terminal MMBL-domain. LlpA mutant proteins with a sterically occluded mannose-binding site displayed a reduced antibacterial function, clearly coupling the ability to bind carbohydrates with bacteriotoxicity. Differential activity of engineered domain chimers derived from two LlpA homologues with different killing spectra, revealed that the N-domain is the main determinant of target strain recognition. Plant MMBL proteins display a diverse range of antagonistic activities, including antifungal, insecticidal, nematicidal or antiviral function, but antibacterial activity could not be demonstrated however. Hence, assigning a bacteriocin to the MMBL family further expands its range of antagonistic functions.The MMBL domain is commonly found in eukaryotic lectins, being particularly widespread among plants but also recently identified in several fish and fungal species. In the proteomes of prokaryotes, this MMBL module may appear as a single unit, in tandem organization, or as a hybrid fused to at least one other domain. The former domain architectures are typically found in Gram-negative bacteria, particularly abundant among Pseudomonas and Burkholderia, while the latter are more often found in Gram-positive bacteria. So far, only one such hybrid protein, composed of a MMBL module fused to a putative peptidase domain, has been characterized. This protein, albusin B, equally acts as a bacteriocin. Phylogenetic analysis of the different MMBL domains from LlpAs demonstrated that N- and C-modules evolved separately: N-domains tend to cluster together, distant from equally clustered C-domains. This observation is in line with the functional segregation described previously. The antibacterial potentialof tandem-MMBL proteins retrieved from proteomes of different bacterial species from Pseudomonas, Xanthomonas and Burkholderia was explored. Using recombinantly-purified proteins, we were able to demonstrate narrow-spectrum, genus-specific activity for all these LlpAs. As different human and phytopathogenic strains are susceptible to these LlpAs, these results may provide interesting perspectives for future antibacterial strategies.An atypical tandem-MMBL protein was identified in an Arthrobacter strain. Having two highly homologous B-lectin modules, six perfectly conserved mannose-binding motifs, a virtually absent ß-hairpin and an oligomeric organization, it represents the sole LlpA-like protein identified in a Gram-positive bacterium so far. We were not able to identify an antibacterial function for this protein, but instead demonstrated anti-retroviral activity. Hence, this protein was called arthrohivin.In several pseudomonad genomes, a single-MMBL-domain protein, termed LlpB, is encoded. This protein displays antibacterial activity as well, which stands in contrast with the task division between domains in LlpA. LlpBs display pronounced similarity with the N-domains of LlpAs, which enabled to construct a model of LlpB based on the crystal structure of the LlpA from P. putida. Based on this structural prediction, LlpB can be assigned to the class of the MMBL proteins as well. This novel subtype lectin-like bacteriocin may represent a kind of minimal LlpA, with target strain recognition and carbohydrate-binding function, if present, condensed into only a single domain. Conceivably, domain duplication within an ancestral LlpB protein, may have given rise to the tandem architecture of LlpA proteins, as a way to diversify target recognition, uncoupled from actual killing activity." "Importance and Diversity of Mycorrhizae under plantain cultivation in the slash-and-burn and non-burn cropping system in the forest region of Kisangani, Tshopo Province, D.R. Congo" "Rony Swennen" "Mycorrhization is known to have beneficial effects on growth vigour and protection against certain pathogens in several plant species including plantains, which has so far been little studied in the Kisangani forest region. This study aimed to determine the importance and biodiversity of mycorrhizae under plantains in the slash-and-burn and non-burn cropping system. The overall mycorrhization rate was 40.75%. The mycorrhizal spore number was higher in non-burned fields than in burned fields. Vigorous plants revealed a higher number of spores than non-vigorous plants. Genera of mycorrhizal spores identified are Glomus sp. (54.96%); Gigaspora sp. (27.84%); Acaulospora sp. (10.50%) and Scutellospora sp. (6.71%). The presence of trees in banana plantations at high density positively influenced mycorrhization to a small extent."