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Despite the increasing number of solved crystal structures of allergens, the key question why some proteins are allergenic and the vast majority is not remains unanswered. The situation is not different for fungal allergens which cover a wide variety of proteins with different chemical properties and biological functions. They cover enzymes, cell wall, secreted, and intracellular proteins which, except cross-reactive allergens, does not show any evidence for structural similarities at least at the three-dimensional level. However, from a diagnostic point of view, pure allergens biotechnologically produced by recombinant technology can provide us, in contrast to fungal extracts which are hardly producible as standardized reagents, with highly pure perfectly standardized diagnostic reagents.

BACKGROUND Companion animals are also affected by IgE-mediated allergies, but the eliciting molecules are largely unknown. We aimed at refining an allergen microarray to explore sensitization in horses and compare it to the human IgE reactivity profiles. METHODS Custom-designed allergen microarray was produced on the basis of the ImmunoCAP ISAC technology containing 131 allergens. Sera from 51 horses derived from Europe or Japan were tested for specific IgE reactivity. The included horse patients were diagnosed for eczema due to insect bite hypersensitivity, chronic coughing, recurrent airway obstruction and urticaria or were clinically asymptomatic. RESULTS Horses showed individual IgE-binding patterns irrespective of their health status, indicating sensitization. In contrast to European and Japanese human sensitization patterns, frequently recognized allergens were Aln g 1 from alder and Cyn d 1 from Bermuda grass, likely due to specific respiratory exposure around paddocks and near the ground. The most prevalent allergen for 72.5% of the tested horses (37/51) was the 2S-albumin Fag e 2 from buckwheat, which recently gained importance not only in human but also in horse diet. CONCLUSION In line with the One Health concept, covering human health, animal health and environmental health, allergen microarrays provide novel information on the allergen sensitization patterns of the companion animals around us, which may form a basis for allergen-specific preventive and therapeutic concepts.

Robotics-based high throughput screening of Aspergillus fumigatus cDNA libraries displayed on phage surfaces revealed at last 81 different structures able to bind IgE from serum of patients sensitized to this fungus. Among these, species-specific as well as phylogenetically highly conserved structures and such with unknown function have been detected. A subset of cDNAs have been used to produce and characterize the corresponding recombinant allergens which have proven to be useful diagnostic reagents allowing specific detection of A. fumigatus sensitization and differential diagnosis of allergic bronchopulmonary aspergillosis. Phylogenetically highly conserved structures like manganese-dependent superoxide dismutase, P2 acidic ribosomal protein, cyclophilins and thioredoxins induce, beyond sensitization, IgE antibodies able to cross-react with the corresponding homologous self antigens. These reactions, likely to contribute to the exacerbation and perpetuation of allergic bronchopulmonary aspergillosis, can be traced back to shared conformational B-cell epitopes build up from conserved amino acid residues scattered over the surface of the molecules as shown by detailed analyses of the crystal structures.

A lack of correlation between systemic and local IgE production at mucosal sites has been reported for allergic asthma [1–5], allergic rhinitis [6, 7] and chronic rhinosinusitis with nasal polyps [8–10]. In allergic asthmatics, local IgE production is higher than in nonallergic asthmatics [3] and high local IgE levels have been linked to the clinical phenotype. Interestingly, in cases of nasal polyps, local IgE targets mainly superantigens [8]., IgE responses to Aspergillus fumigatus in cystic fibrosis lungs http://ow.ly/XXwv30furqs

The development of vaccines inducing efficient CD8+ T cell responses is the focus of intense research. Dendritic cells (DCs) expressing the XCR1 chemokine receptor, also known as CD103+ or CD8α+ DCs, excel in the presentation of extracellular Ags to CD8+ T cells. Because of its high numbers of DCs, including XCR1+ DCs, the skin dermis is an attractive site for vaccine administration. By creating laser-generated micropores through the epidermis, we targeted a model protein Ag fused to XCL1, the ligand of XCR1, to dermal XCR1+ DCs and induced Ag-specific CD8+ and CD4+ T cell responses. Efficient immunization required the emigration of XCR1+ dermal DCs to draining lymph nodes and occurred irrespective of TLR signaling. Moreover, a single intradermal immunization protected mice against melanoma tumor growth in prophylactic and therapeutic settings, in the absence of exogenous adjuvant. The mild inflammatory milieu created in the dermis by skin laser microporation itself most likely favored the development of potent T cell responses in the absence of exogenous adjuvants. The existence of functionally equivalent XCR1+ dermal DCs in humans should permit the translation of laser-assisted intradermal delivery of a tumor-specific vaccine targeting XCR1+ DCs to human cancer immunotherapy. Moreover, considering that the use of adjuvants in vaccines is often associated with safety issues, the possibility of inducing protective responses against melanoma tumor growth independently of the administration of exogenous adjuvants should facilitate the development of safer vaccines.

The availability of allergen molecules ('components') from several protein families has advanced our understanding of immunoglobulin E (IgE)-mediated responses and enabled 'component-resolved diagnosis' (CRD). The European Academy of Allergy and Clinical Immunology (EAACI) Molecular Allergology User's Guide (MAUG) provides comprehensive information on important allergens and describes the diagnostic options using CRD. Part A of the EAACI MAUG introduces allergen molecules, families, composition of extracts, databases, and diagnostic IgE, skin, and basophil tests. Singleplex and multiplex IgE assays with components improve both sensitivity for low-abundance allergens and analytical specificity; IgE to individual allergens can yield information on clinical risks and distinguish cross-reactivity from true primary sensitization. Part B discusses the clinical and molecular aspects of IgE-mediated allergies to foods (including nuts, seeds, legumes, fruits, vegetables, cereal grains, milk, egg, meat, fish, and shellfish), inhalants (pollen, mold spores, mites, and animal dander), and Hymenoptera venom. Diagnostic algorithms and short case histories provide useful information for the clinical workup of allergic individuals targeted for CRD. Part C covers protein families containing ubiquitous, highly cross-reactive panallergens from plant (lipid transfer proteins, polcalcins, PR-10, profilins) and animal sources (lipocalins, parvalbumins, serum albumins, tropomyosins) and explains their diagnostic and clinical utility. Part D lists 100 important allergen molecules. In conclusion, IgE-mediated reactions and allergic diseases, including allergic rhinoconjunctivitis, asthma, food reactions, and insect sting reactions, are discussed from a novel molecular perspective. The EAACI MAUG documents the rapid progression of molecular allergology from basic research to its integration into clinical practice, a quantum leap in the management of allergic patients.

There have been extensive developments on cellular and molecular mechanisms of immune regulation in allergy, asthma, autoimmune diseases, tumor development, organ transplantation, and chronic infections during the last few years. Better understanding the functions, reciprocal regulation, and counterbalance of subsets of immune and inflammatory cells that interact through interleukins, interferons, TNF-α, and TGF- β offer opportunities for immune interventions and novel treatment modalities in the era of development of biological immune response modifiers particularly targeting these molecules or their receptors. More than 60 cytokines have been designated as interleukins since the initial discoveries of monocyte and lymphocyte interleukins (called IL-1 and IL-2, respectively). Studies of transgenic or gene- deficient mice with altered expression of these cytokines or their receptors and analyses of mutations and polymorphisms in human genes that encode these products have provided essential information about their functions. Here we review recent developments on IL-1 to IL-38, TNF-α, TGF-β, and interferons. We highlight recent advances during the last few years in this area and extensively discuss their cellular sources, targets, receptors, signaling pathways, and roles in immune regulation in patients with allergy and asthma and other inflammatory diseases.

BackgroundAtopic dermatitis (AD) is a complex chronic inflammatory disease where allergens can act as specific triggering factors.AimTo characterize the specificities of IgE-reactivity in patients with AD to a broad panel of exogenous allergens including microbial and human antigens.MethodologyAdult patients with AD were grouped according to the SCORAD index, into severe (n = 53) and moderate AD (n = 126). As controls 43 patients were included with seborrhoeic eczema and 97 individuals without history of allergy or skin diseases. Specific IgE reactivity was assessed in plasma using Phadiatop®, ImmunoCap™, micro-arrayed allergens, dot-blotted recombinant Malassezia sympodialis allergens, and immune-blotted microbial and human proteins.ResultsIgE reactivity was detected in 92% of patients with severe and 83% of patients with moderate AD. Sensitization to cat allergens occurred most frequently, followed by sensitization to birch pollen, grass pollen, and to the skin commensal yeast M. sympodialis. Patients with severe AD showed a significantly higher frequency of IgE reactivity to allergens like cat (rFel d 1) and house dust mite (rDer p 4 and 10), to Staphylococcus aureus, M. sympodialis, and to human antigens. In contrast, there were no significant differences in the frequencies of IgE reactivity to the grass pollen allergens rPhl p 1, 2, 5b, and 6 between the two AD groups. Furthermore the IgE reactivity profile of patients with severe AD was more spread towards several different allergen molecules as compared to patients with moderate AD.ConclusionWe have revealed a hitherto unknown difference regarding the molecular sensitization profile in patients with severe and moderate AD. Molecular profiling towards allergen components may provide a basis for future investigations aiming to explore the environmental, genetic and epigenetic factors which could be responsible for the different appearance and severity of disease phenotypes in AD.

Background Allergen specific immunotherapy (SIT) faces problems related to side effects and limited efficacy. Direct administration of allergen extracts into lymph nodes induces increased specific IgG production and T cell responses using significantly lower allergen doses. Methods In this study mechanisms of immune regulation by MAT vaccines in vitro and in allergen SIT of cat Allergic rhinitis patients who received 3 inguinal intra lymph node injections of MAT Fel d 1 vaccine were investigated in PBMC and cell cultures for specific T cell proliferation Fel d 1 tetramer specific responses and multiple immune regulatory molecules. Results MAT Fel d 1 vaccine was efficiently internalized by antigen presenting cells. This was followed by precaspase 1 cleavage to caspase 1 and secretion of IL 1ß indicating inflammasome activation. Mat Fel d 1 induced specific T cell proliferation and an IL 10 and IFN ? dominated T cell responses with decreased Th2 cytokines at 100 times lower doses than Fel d 1. Induction of immune tolerance by MAT Fel d 1 ILIT involved multiple mechanisms of immune suppression. Early Fel d 1 specific T cell activation was followed by full T cell unresponsiveness to allergen after 1 year in the MAT Fel d 1 group characterized by increased allergen specific T regulatory cells decreased circulating Fel d 1 tetramer positive cells increased IL 10 and FOXP3 expression and change in the HR2/HR1 ratio toward HR2. Conclusions This study demonstrates the induction of allergen tolerance after 3 intra lymph node injections of MAT Fel d 1 vaccine mediated by increased cellular internalization of the allergen activation of inflammasome and generation of allergen specific peripheral T cell tolerance. © 2014 John Wiley Sons A/S. Published by John Wiley Sons Ltd.

Background/Aim/Method The induction of CD8+ cytotoxic T lymphocytes (CTL) is critical to eradicate tumor cells. In mouse skin, a subset of dendritic cell characterised by the expression of the chemokine receptor XCR1 is highly potent to activate CD8+ T cells. By combining PLEASE-assisted laser poration of the skin allowing dermal delivery and the use of dimeric vaccine molecule in which the XCR1 ligand, Xcl1, was fused to the antigen, we targeted specifically this XCR1+ dermal subset. Results Dermal delivery of this vaccine molecule after skin laser-poration induced specific strong T cell proliferation in an XCR1-dependent manner. A single immunization allowed protecting against melanoma in both therapeutic and prophylactic protocols. Discussion & Conclusion Thus, specific targeting of cross-presenting skin DCs represents a promising vaccine strategy for induction of CD8+ T cell responses and protection against cancers. Citation Format: Dorothea Terhorst, Even Fossum, Anna Baranska, Samira Tamoutounour, Camille Malosse, Mattia Garbani, Elmira Lechat, Reto Crameri, Roland Winteler, Bjarne Bogen, Bernard Malissen, Sandrine Henri. Effective vaccination against melanoma in an animal study: Combination of laser-assisted dermal skin delivery and cross-presenting XCR1+ dermal DCs targeting. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2518. doi:10.1158/1538-7445.AM2015-2518