Background: Despite the clinical severity and rising prevalence of peanut allergy, there is a marked absence of widespread, practical treatments available for peanut-allergic patients. Peptide immunotherapy, a disease-modifying treatment that uses short peptides recognized by T cells, has been shown to reduce allergic symptoms of allergic rhinoconjunctivitis. This project investigated the ability of peptides from the major peanut allergen Ara h 1 to protect against peanut-induced anaphylaxis and induce immunomodulatory changes in a mouse model. Methods: Mice transgenic for the human leukocyte antigen DRB1*0401 were sensitized to peanut epicutaneously and treated with two intraperitoneal injections of peptides from Ara h 1. Mice were then challenged with intraperitoneal whole peanut and observed for signs of anaphylaxis. Flow cytometry was used to isolate peanut-specific CD4+ T cells labelled with Ara h 1 peptide-loaded tetramers and additional Th1, Th2, and regulatory markers. Results: Peptide-treated mice were protected from severe peanut-induced anaphylaxis. Control mice treated with a sham peptide experienced a mean maximum temperature drop of 3.2°C, while mice treated with Ara h 1 peptides experienced a drop of 1.6°C (p=0.067 vs control). Maximum clinical score was 2.5 in control mice, and 1.4 in treated mice (p=0.0097). Mean hematocrit for control mice was 52.5%, and 47% for treated mice (p=0.013). PD-1+CD4+ T cells were significantly increased in the mesenteric lymph nodes (p = 2.28e-0.05) and spleens (p = 0.014) of peptide-treated mice. MIP1-a+CD4+ T cells were significantly decreased in the peritoneal lavage (p = 0.008). Conclusion: Ara h 1 peptide immunotherapy protected against severe peanut-induced anaphylaxis in a mouse model. Peptide-treated mice experienced significantly reduced drops in core body temperature, clinical signs of allergic reaction, and hemoconcentration. Clinical protection was associated with decreased expression of the pro-inflammatory chemokine macrophage 1-a and increased expression of the surface marker programmed cell death protein 1. / Thesis / Doctor of Philosophy (PhD) / Peanut allergy is a growing public health concern. Its prevalence has doubled in the past 10 years and currently stands at 2%. Reactions to peanut account for the majority of food-induced fatal allergic reactions, termed anaphylaxis. Currently, there are no treatments available for patients with peanut allergy. Healthcare workers can only offer peanut-allergic patients advice on peanut avoidance and rescue medications in case of accidental ingestion. This research project investigated the ability of a new treatment called peptide immunotherapy to prevent severe allergic reactions to peanut in a mouse model of peanut allergy. Peptide treatment uses small portions of the peanut allergen to shift the immune response from pro-inflammatory to anti-inflammatory. After peptide treatment, peanut-allergic mice were protected from severe allergic reactions in response to peanut and their immune cells produced lower levels of pro- inflammatory molecules.

Fungi are one of the major organisms that cause allergic disease in human. A number of proteins from fungi have been found to be allergenic or possess immunostimulatory properties. Identifying and characterizing allergens from fungal genomes will help facilitate our understanding of the mechanism underlying host-pathogen interactions in allergic diseases. Currently, there is a lack of tools that allow us to rapidly and accurately predict allergens from whole genomes. In the context of whole genome annotation, allergens are rare compared to non-allergens and thus the data is considered highly skewed. In order to achieve a confident set of predicted allergens from a genome, false positive rates must be lowered. Current allergen prediction tools often produce many false positives when applied to large-scale data set such as whole genomes, and thus lower the precision. Moreover, the most accurate tools are relatively slow because they use sequence alignment to construct feature vectors for allergen classifiers. This dissertation presents computational approaches in characterizing the allergen repertoire in fungal genomes as part of the whole genome studies of Alternaria, an important allergenic/opportunistic human pathogenic fungus and necrotrophic plant parasite. In these studies, the genomes of multiple Alternaria species were characterized for the first time. Functional elements (e.g. genes, proteins) were first identified and annotated from these genomes using computational tools. Protein annotation and comparative genomics approaches revealed the link between Alternaria genotypes and its prolific saprophytic lifestyle that provides at least a partial explanation for the development of pathological relationships between Alternaria and humans. A machine learning based tool (Allerdictor) was developed to address the neglected problem of allergen prediction in highly skewed large-scale data sets. Allerdictor exhibited high precision over high recall at fast speed and thus it is a more practical tool for large-scale allergen annotation compared with existing tools. Allerdictor was then used together with a comparative genomics approach to survey the allergen repertoire of known allergenic fungi. We predicted a number of mold allergens that have not been experimentally characterized. These predicted allergens are potential candidates for further experimental and clinical validation. Our approaches will not only facilitate the study of allergens in the increasing number of sequenced fungal genomes but also will be useful for allergen annotation in other species and rapid prescreening of synthesized sequences for potential allergens. / Ph. D.

Yes / In this commentary, we focus on allergy as a facilitating factor in the pathogenesis of alopecia areata (AA). From previous studies on AA, it is well known that subsets of patients can have one or more of; seasonal relapse, comorbid atopic rhinitis, asthma and dermatitis, lesion infiltrating eosinophils and plasma cells, high levels of total IgE, specific IgE for house dust mites (HDMs), and/or disrupted skin barrier function by the evaluation of filaggrin. Allergy and AA share a similar genetic background; both contributing to an immune reaction imbalance. Furthermore, adjunctive treatment with antihistamines, or desensitization for HDM, can reduce the severity of alopecia in atopic AA patients. Therefore, allergies may contribute to the onset and relapse of AA. Identification of an allergic or atopic immune component in AA patient subsets may indicate adjunctive treatment intervention measures against allergies should be taken which may improve the success of conventional AA treatment.

Current biologics often fail to effectively manage symptoms in severe allergic asthmatic patients, necessitating the exploration of novel therapeutic approaches. Our laboratory has recently identified Lectin Mannose Binding 1 (LMAN1) as a regulatory cell surface receptor for house dust mite (HDM). Binding of LMAN1 to HDM allergens was found to depend on mannosylation, suggesting a potential broader role of this receptor in the recognition of other highly mannosylated allergens such as molds. Alternaria alternata (A. alternata) is a ubiquitous mold often associated with severe asthma. Whether LMAN1 can also act to regulate responses to A. alternata, remains to be explored. To this end, we subjected both WT and LMAN1 knockout mice to an A. alternata-induced asthma model. The absence of LMAN1 resulted in a substantial increase in airway hyperresponsiveness (AHR). Interestingly, changes in AHR did not correlate with either eosinophil or neutrophil infiltration into the lung but instead, went hand in hand with a reduction in alveolar macrophages and an increase in type-2 innate lymphoid cells. Work is currently ongoing to further investigate the cellular and molecular mechanisms underlying these findings. This discovery highlights LMAN1 as a promising target for innovative therapeutic interventions.

Objetivo: O objetivo desse estudo foi avaliar alterações na resposta clínica e imunológica ao camarão após a imunoterapia com Dermatophagoides pteronyssinus. Métodos: Selecionou-se 35 indivíduos alérgicos a Dermatophagoides pteronyssinus (Der p), os quais foram submetidos a testes cutâneos de leitura imediata para ácaros, baratas, camarão, tropomiosina recombinante, além de cão, gato e fungos. A detecção de IgE espcífica in vitro foi feita para o ácaro, camarão, barata americana e para suas tropomiosinas. Em todos, avaliou-se reatividade clínica ao camarão através de provocação oral. Dez pacientes foram alocados para o grupo controle, e 25 foram submetidos à imunoterapia alérgeno específica para o ácaro. Os testes cutâneos e a dosagem de IgE sérica específica foram repetidas após a indução da imunoterapia, e após 1 ano do início. A reatividade clínica ao camarão foi reavaliada no final do estudo pela provocação oral. Resultados: No grupo dos pacientes que foram submetidos à imunoterapia, observamos diminuição na reatividade nos testes cutâneos e dosagem de IgE específica para Der p, camarão e tropomiosina recombinante. Dos 10 pacientes com testes cutâneos positivos para camarão, 4 foram negativos na dosagem após um ano de imunoterapia (p= 0,04). Quanto à dosagem sérica de IgE para camarão, dos 9 positivos no início, 6 ficaram negativos (p= 0,014). Nenhum paciente submetido a imunoterapia desenvolveu nova sensibilização para camarão. Não houve alteração na reatividade clínica ao camarão após imunoterapia. Conclusão: A imunoterapia para Dermatophagoides pteronyssinus foi acompanhada de diminuição da reatividade imunológica para camarão e clinicamente não houve alteração da sensibilidade a camarão / Objective: The objective of this study was to determine changes in clinical and immunological response to shrimp after immunotherapy with Dermatophagoides pteronyssinus. Methods: We studied 35 allergic subjects to Dermatophagoides pteronyssinus (Der p), submitted to skin tests to mites, cockroach, shrimp, recombinant tropomyosin, and dog, cat and fungi. The detection of serum specific IgE was performed to mite, shrimp, and tropomyosin from American cockroach. In all patients, the clinical reactivity to shrimp was assessed through oral challenge. Ten patients were allocated to the control group, and 25 were submitted to immunotherapy for mite. Skin tests and determination of serum specific IgE were repeated after the induction of immunotherapy (3-4 months) and 1 year after of beginning of the treatment. The clinical reactivity to shrimp was assessed again at the end of the study by oral challenge. Results: In the group of patients who were undergoing immunotherapy, we observed decreased reactivity in the skin tests and specific IgE levels to Der p, shrimp and recombinant tropomyosin. Among the 10 patients with positive skin tests to shrimp, 4 were negative when assessed after one year of immunotherapy (p = 0.04). About serum specific IgE to shrimp, from the 9 positive reactors in the beginning of treatment, 6 became negative (p= 0.014). There was no change in clinical reactivity to shrimp after immunotherapy. Conclusion: The immunotherapy for Dermatophagoides pteronyssinus was accompanied by decreased immune reactivity to shrimp and clinically there was no change in sensitivity to shrimp

No description available.

Objetivo: O objetivo desse estudo foi avaliar alterações na resposta clínica e imunológica ao camarão após a imunoterapia com Dermatophagoides pteronyssinus. Métodos: Selecionou-se 35 indivíduos alérgicos a Dermatophagoides pteronyssinus (Der p), os quais foram submetidos a testes cutâneos de leitura imediata para ácaros, baratas, camarão, tropomiosina recombinante, além de cão, gato e fungos. A detecção de IgE espcífica in vitro foi feita para o ácaro, camarão, barata americana e para suas tropomiosinas. Em todos, avaliou-se reatividade clínica ao camarão através de provocação oral. Dez pacientes foram alocados para o grupo controle, e 25 foram submetidos à imunoterapia alérgeno específica para o ácaro. Os testes cutâneos e a dosagem de IgE sérica específica foram repetidas após a indução da imunoterapia, e após 1 ano do início. A reatividade clínica ao camarão foi reavaliada no final do estudo pela provocação oral. Resultados: No grupo dos pacientes que foram submetidos à imunoterapia, observamos diminuição na reatividade nos testes cutâneos e dosagem de IgE específica para Der p, camarão e tropomiosina recombinante. Dos 10 pacientes com testes cutâneos positivos para camarão, 4 foram negativos na dosagem após um ano de imunoterapia (p= 0,04). Quanto à dosagem sérica de IgE para camarão, dos 9 positivos no início, 6 ficaram negativos (p= 0,014). Nenhum paciente submetido a imunoterapia desenvolveu nova sensibilização para camarão. Não houve alteração na reatividade clínica ao camarão após imunoterapia. Conclusão: A imunoterapia para Dermatophagoides pteronyssinus foi acompanhada de diminuição da reatividade imunológica para camarão e clinicamente não houve alteração da sensibilidade a camarão / Objective: The objective of this study was to determine changes in clinical and immunological response to shrimp after immunotherapy with Dermatophagoides pteronyssinus. Methods: We studied 35 allergic subjects to Dermatophagoides pteronyssinus (Der p), submitted to skin tests to mites, cockroach, shrimp, recombinant tropomyosin, and dog, cat and fungi. The detection of serum specific IgE was performed to mite, shrimp, and tropomyosin from American cockroach. In all patients, the clinical reactivity to shrimp was assessed through oral challenge. Ten patients were allocated to the control group, and 25 were submitted to immunotherapy for mite. Skin tests and determination of serum specific IgE were repeated after the induction of immunotherapy (3-4 months) and 1 year after of beginning of the treatment. The clinical reactivity to shrimp was assessed again at the end of the study by oral challenge. Results: In the group of patients who were undergoing immunotherapy, we observed decreased reactivity in the skin tests and specific IgE levels to Der p, shrimp and recombinant tropomyosin. Among the 10 patients with positive skin tests to shrimp, 4 were negative when assessed after one year of immunotherapy (p = 0.04). About serum specific IgE to shrimp, from the 9 positive reactors in the beginning of treatment, 6 became negative (p= 0.014). There was no change in clinical reactivity to shrimp after immunotherapy. Conclusion: The immunotherapy for Dermatophagoides pteronyssinus was accompanied by decreased immune reactivity to shrimp and clinically there was no change in sensitivity to shrimp

One of the most common reasons people seek primary care and emergency care is to reduce the symptoms of allergies, such as hay fever. To meet this high demand, several recent FDA-approved methods for treating seasonal and perennial allergies have been developed, including sublingual immunotherapy tablets. Furthermore, no longer must a patient endure allergy shots; this can now be delivered sublingually. Although this method has been shown to have high safety and efficacy, very few clinicians actually utilize this form of therapy. The purpose of this paper is describe the use of sublingual immunotherapy among Nurse Practitioners (NPs) and discuss barriers that may prevent its use. Nurse Practitioners working in primary care settings were surveyed regarding their use of sublingual immunotherapy. Although many nurse practitioners treat patients with allergic disease, not one participant reported using sublingual immunotherapy. This discussion outlines some of the reasons NPs are not currently utilizing this method of allergy treatment and the findings are compared with the extant literature. This paper culminates in an evidence-based algorithm to outline best practices for utilizing sublingual immunotherapy to reduce allergy symptoms.

[ Truncated abstract ] Atopic diseases such as asthma are thought to be driven to a significant extent by T helper memory cells which are programmed to respond in a harmful way to environmental allergens (e.g. house dust mite). Previous studies in humans and in animal models have established that activation of TH2 cytokine genes in T memory responses to allergens is central to the disease process. However, only a subset of atopics harbouring a TH2-memory response phenotype manifests clinical symptoms of disease. Moreover, clinical trials with TH2 antagonists in atopic patients have proven disappointing, suggesting underlying complexities in disease pathogenesis which escape regulation via these approaches. It was thus hypothesised that additional genes involved in the activation program of allergen-specific T memory cells which are central to disease pathogenesis remain unidentified. The aim of the current study was to identify such novel genes by applying microarray technology to survey genome-wide expression patterns in an in vitro model of allergen-driven human T cell activation. In contrast to previous human microarray studies in this area focusing on mitogen activated T cell lines and clones, the current study avoided the use of strong activation stimuli which have the potential to distort patterns of gene expression, and reports for the first time the findings of microarray analysis of house dust mite allergen-driven acute gene activation in recirculating T memory cells harvested from the peripheral blood of human atopics. ... Finally, methodology was established to investigate the function of the novel atopy-associated genes. In loss-of-function experiments, expression of DACT1 and CAMK2D was silenced in primary T cell responses driven by bacterial superantigens, a model system for studying T cell responses under conditions which mimic antigen-specific activation. Whilst silencing DACT1 and CAMK2D expression did not influence classical readouts of T cell function including proliferation and cytokine production, microarray profiling was employed to identify putative downstream transcriptional targets of each gene. The experimental strategy and optimised methodology presented herein can now be employed to investigate the molecular circuitry linking the novel atopy-associated genes to the T cell activation process. In conclusion, several novel genes associated with allergen-driven T memory responses in atopics have been first described in this thesis and represent logical candidates for more detailed immunological and genetic studies related to the pathogenesis of atopic diseases.

Thesis (Ph.D.)--University of Western Australia, 2008.