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Existem fortes evidências de que a supressão da hipersensibilidade nos recém nascidos pode ser mediada pela transferência de anticorpos maternos, dependendo de sua concentração e especificidade, no entanto carece estudos sobre a eficácia em humanos. Realizamos este estudo a fim de caracterizar qualitativa e quantitativamente a transmissão de anticorpos direcionados ao principal alérgeno da poeira domiciliar (Der p) via placenta e colostro materno, assim como investigar o efeito da sensibilização materna ao Der p na transferência passiva destes anticorpos. Para tais objetivos, analisamos amostras de sangue materno, cordão umbilical e colostro de puérperas sensibilizadas. Demonstramos pela primeira vez que S-IgA anti-Der p pode ser transferida ao lactente em concentrações bastante variáveis e com alto índice de avidez, independente da sensibilização materna ao mesmo ácaro. Demonstramos também que o nível de IgG específica ao Der p é mais elevado em recém nascidos de mães sensibilizadas quando comparado aos de mães controle não sensibilizadas. Já a avidez específica da IgG anti-Der p foi muito semelhante entre as amostras pareadas de cordão umbilical e soro materno, assim como em amostras do grupo estudo e grupo controle. / It is known that the incidence of allergic disease has been rising very fast in the last decade and nowadays affects thousands of children worldwide. For this reason, it is of great interest that efficient strategies of prevention of atopy should be applied in the first years of life or even before birth. The are strong evidences that the suppression of hypersensitivity in newborn can be mediated by the transference of maternal antibodies, depending on their concentration and specificity, however still little is known about the mechanisms involving, in special in humans. We made this study aiming to characterize qualitatively and quantitatively the antibodies transmission directed to the main home dust allergen (Dermatophagoides pteronyssinus; Der p) through placental transference and maternal breastfeeding as well as to investigate the maternal sensitizing effect against to Der p in passive transference of these antibodies. For those objectives, we quantified by ELISA, IgG anti-Der p in paired samples of maternal blood and umbilical cord and anti-Der p S-IgA in colostrums of sensitized mother (n=13) and not sensitized (n=26); and we analyzed the functional activity of the same antibodies by avidity assays. The sensibility was determined in maternal sera by specific RAST (Cap System® Pharmacia). We show by the first time that anti-Der p S-IgA is transferred to the infant in very variable concentrations and with high levels of avidity, but is not dependent of maternal sensitization. We believe that breastfeeding is important, because it supplies S-IgA with the capacity to neutralize in a specific manner and block the entrance of Der p through mucosa, in infant of RAST+ mothers as well as of RAST-. We also demonstrate that total and specific to Der p IgG levels are more elevated in newborns of sensitized mothers when compared to of those of control mothers and non-sensitized indicating that the maternal sensitizing can influence the fetal immune response. In the other hand, the specific avidity of anti-Der p IgG was very similar between paired samples of umbilical cord and maternal sera, as well as in samples of study group and control group, suggesting thar the avidity index of IgG does not influence on placental transfer of specific antibodies. Once that the maternal antibody transference represent a important mechanism for immunomodulation of allergic response, we expect that a better understanding of the influence of maternal sensitivity on passive transfer of specific antibodies to babies will contribute with advances in the elaboration of adequate strategies of prevention of allergic sensitivity with more efficient therapeutic results.

Exposição a alérgenos de poeira doméstica é fator de risco para o desenvolvimento de doenças alérgicas. Os objetivos foram estudar a resposta inflamatória pulmonar alérgica induzida pela sensibilização i.n. ou s.c. ao extrato do ácaro Blomia tropicalis (Bt) e avaliar a participação da molécula adaptadora Myd88. Animais C57BL/6 sensibilizados com solução de extrato de Bt adsorvido ao alum exibiram altos níveis de IgE e aumento do número de eosinófilos. Contudo, animais sensibilizados apenas com Bt não apresentaram aumento dos níveis de IgE. Assim, animais C57BL/6 ou MyD88KO foram sensibilizados com uma dose maior do extrato de Bt (i.n. ou s.c.) e desafiados i.n. As sensibilizações produziram aumento do número células no BAL e níveis de IgE. Os parâmetros celulares em animais MyD88KO se mostraram inibidos, contudo, os níveis de IgE foram similares aos dos animais WT. Concluindo, o desenvolvimento de inflamação pulmonar alérgica não requer alum e sensibilização i.n. ou s.c. induz o recrutamento de células, dependente de MyD88 e produção de IgE, independe de MyD88. / Exposure to allergens from house dust is a risk factor for the development of allergic diseases. The objectives were to study the allergic lung inflammatory response induced by sensitization i.n. or s.c. to Blomia tropicalis (Bt) extract and determine the role of MyD88 adapter molecule. C57BL/6 mice sensitized with Bt extract solution adsorbed to alum exhibited high levels of IgE and increased numbers of eosinophils. However, animals sensitized only with Bt did not show increased levels of IgE. Thus, C57BL/6 or MyD88KO mice were sensitized with a higher dose of Bt extract (i.n. or s.c.) and challenged i.n. The sensitization produced increased cell number in BAL and IgE serum levels. Cell parameters were inhibited in MyD88KO mice, however, IgE levels were similar to those of WT mice. In conclusion, the development of allergic lung inflammation does not require alum, i.n. or s.c. sensitization induces cell recruitment dependent of MyD88 adaptor molecule and IgE production is independent of MyD88.

Dissertation (Ph.D.)--Auburn University, 2009. / Abstract. Includes bibliographic references.

This research investigated seasonal climate changes within greenhouses and the impacts they have on efficacy of the predatory mites Amblyseius swirskii and Neoseiulus cucumeris. Controlled environment chamber, greenhouse small-cage, and commercial greenhouse trials were conducted to determine which biological control agent is more efficacious for control of the pest western flower thrips (WFT), (Frankliniella occidentalis) on ornamental crops. When observed under laboratory conditions, predation and oviposition were increased at higher temperatures. Photoperiod and light intensity also have an impact on predatory mites. Predation rates for both mite species were greater when subjected to short day light conditions (8 h light, 11 W/m2). Climates typical of summer (higher temperature and light intensity, long day length), were most favourable in terms of predation and oviposition for A. swirskii. Neoseiulus cucumeris laid more eggs under short day as opposed to long day settings. In summer and winter greenhouse small cage trials, the performance of N. cucumeris and A. swirskii significantly reduced WFT numbers on potted chrysanthemum plants. However, in summer, A. swirskii provided significantly better thrips control than N. cucumeris. The number of adult mites recovered from plants was similar for both mite treatments in winter, while A. swirskii were present in higher numbers throughout the summer trials. Results from leaf damage assessments indicate that A. swirskii is more effective for control of heavy WFT feeding damage in both summer and winter. Results from commercial greenhouse trials yielded similar trends as those found in the summer and winter small cage trials. / University of Guelph, Agriculture and Agri-Food Canada, Vineland Research and Innovation Center, Flowers Canada

Boreal regions account for a significant portion of Canada's landmass and economic resources (e.g., forestry, mining, and oil and gas). The inadvertent release of pollutants from industrial activities within these regions stress the need for realistic ecological risk assessments, which can be attained through the use of standardized soil toxicity test methods. Despite the geophysical and economic significance of boreal regions, standardized soil toxicity test methods applicable to these regions are lacking. To help alleviate this gap in ecotoxicology, the objectives of this thesis included the development and application of a new suite of boreal species for the assessment of contaminants in boreal soils. Specifically, research was directed towards the development of a new oribatid mite test, using Oppia nitens (C.L. Koch). Oribatid mites represent the most abundant and diverse microarthropod species in forest soils, significantly contributing to nutrient cycling and soil formation processes; however, these organisms are consistently under-represented in soil ecotoxicological assessments. The applicability and limitations of the use of O. nitens were demonstrated such that lethal and sublethal endpoints could be derived from the assessment of soils. The performance of O. nitens across numerous soils varied such that adult survival was unaffected by soil characteristics, however, reproduction was limited by soil organic matter content. An evaluation of the sensitivity of O. nitens, using a model polycyclic aromatic hydrocarbon was also conducted in a standard test soil. Phenanthrene is a common contaminant in soils, and accumulates within organic-rich horizons, within which oribatid mites live. Therefore, the study was designed to examine the toxicity and bioaccumulation potential of phenanthrene to O. nitens, with a comparison of effect to other soil invertebrate species, as presented in the literature. Oppia nitens was susceptible to phenanthrene at levels comparable to other soil invertebrate species, and the bioaccumulation of the phenanthrene increased with increasing exposure concentration, although steady-state was not achieved during the four-week exposure duration. The accumulation was biphasic in nature, likely a result of initial cuticular sorption processes, followed by the contribution of other processes (e.g., dietary uptake). The elimination of the phenanthrene was not complete, in that at the end of the elimination phase, tissue residues were similar to that observed in the initial gradual accumulation (e.g., by cuticular processes). However, the resultant bioaccumulation factors (BAFs) were relatively low, indicative of limited trophic transfer and biomagnification for this species. Following the development of an O. nitens assay, a further study was conducted to compare the sensitivity of O. nitens to other boreal soil invertebrate species, as well as to standard test species. Soil toxicity tests were designed, using field-collected reference and contaminated (petroleum hydrocarbon- and salt-impacted) soils, using an expanded suite of boreal species (plants: Pinus banksiana, Picea glauca, Picea mariana, Populus tremuloides, Calamagrostis canadensis and Solidago canadensis; earthworms: Dendrodrilus rubidus; and springtails: Folsomia nivalis and Proisotoma minuta). The sensitivity of the boreal species was then compared to that of currently published standard soil toxicity test species (agronomic plants: Elymus lanceolatus and Trifolium pratense; earthworms: Eisenia andrei; and springtails: Folsomia candida). Estimated species sensitivity distributions (ESSDs) were generated to determine whether the boreal and standard test battery of species exhibited differences in their overall sensitivity to the contaminated soil. With regards to the petroleum-hydrocarbon impacted soil, the suite of boreal species was more sensitive relative to the suite of standard test species; however, upon exposure to the salt-impacted soils, no differences in sensitivity were evident between the boreal and standard suite of test species. In both soils, the performance of O. nitens was similar to that observed by the collembolan species. The evaluation of boreal species and soils also took into consideration the use of distinct soil horizons. The layering of horizons was feasible from the initial collection to reassembly for testing in the laboratory, and plant growth was unaffected by this design. However, soil invertebrates demonstrated a preference or avoidance tendency for one horizon over another, and as a result, the assessment of individual horizons was recommended for all future testing. The compilation of research presented herein provides the basis for the standardization of ecologically-relevant test species and methods for the assessment of contaminated soils in boreal regions.

Thesis (Ph.D.) -- University of Western Sydney, Hawkesbury, 2000. / "A thesis presented in fulfilment of the requirement for the degree of Doctor of Philosophy" Bibliography : leaves 160-183.

Tez (Yüksek Lisans) - Süleyman Demirel Üniversitesi, Fen Bilimleri Enstitüsü, Bitki Koruma Anabilim Dalı, 2008. / Bibliyografya var.

Submitted by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2016-02-15T13:52:56Z No. of bitstreams: 1 Luciana Souza de Aragão França Redução....pdf: 995559 bytes, checksum: ba08fbe35c691051eb1d16b7657f0655 (MD5) / Approved for entry into archive by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2016-02-15T13:53:13Z (GMT) No. of bitstreams: 1 Luciana Souza de Aragão França Redução....pdf: 995559 bytes, checksum: ba08fbe35c691051eb1d16b7657f0655 (MD5) / Made available in DSpace on 2016-02-15T13:53:13Z (GMT). No. of bitstreams: 1 Luciana Souza de Aragão França Redução....pdf: 995559 bytes, checksum: ba08fbe35c691051eb1d16b7657f0655 (MD5) Previous issue date: 2014 / Fundação Oswaldo Cruz, Centro de Pesquisas Gonçalo Moniz. Salvador, BA, Brasil / As alergias afetam cerca de 20 a 30% da população mundial e sua prevalência, bem como a gravidade dos sintomas, tem aumentado nas últimas décadas. As terapias existentes para as desordens do trato respiratório ocorrem por períodos prolongados, apresentam efeitos colaterais, muitas vezes não são efetivas para pacientes graves e dependem do afastamento do alérgeno. Uma alternativa para esses pacientes seria a indução de tolerância imunológica, através da terapia celular com células dendríticas pulsadas com o alérgeno. O presente trabalho objetivou avaliar o efeito de células dendríticas mielóides sensibilizadas in vitro com extrato de B. tropicalis em modelo murino de alergia respiratória. Em modelos experimentais de alergia respiratória, células T auxiliares (Th2) alérgeno-específica produzem citocinas que regulam a síntese de anticorpos IgE alérgeno-específicos e controlam a inflamação eosinofílica e a remodelação do tecido das vias aéreas, e esses parâmetros foram analisados neste trabalho. Células dendríticas tolerogênicas de camundongos A/J foram obtidas na presença de GM-CSF e dexametasona e caracterizadas por apresentarem baixa expressão de MHC-II e moléculas coestimulatórias, redução acentuada de PD-L2 e um perfil antiinflamatório de produção de citocina.A inoculação prévia de células dendríticas sensibilizadascom Blomia reduziu especificamente e significativamente o número total de leucócitos e o número de eosinófilos no fluido de lavagem broncoalveolar e reduziu a produção de IgE, em comparação à inoculação de células sensibilizadas com ovalbumina, e estes efeitos foram mais intensos com uma segunda inoculação de células tolerogênicas. Além disso, redução do infiltrado inflamatório pulmonar foi observada em animais que tinham sido tratados com células dendríticas, independente do antígeno utilizado na sensibilização das mesmas. Estes resultados indicam que células dendríticas geradas como descrito neste trabalho podem inibir uma resposta alérgica Th2. A especificidade do tratamento, entretanto, deve ser melhor investigada. / Allergies affect about 20-30% of world population and its prevalence and severity of symptoms has increased in recent decades. Existing therapies to respiratory tract disorders are extense, with side effects, not effective for severe patients and depending on the allergen removal. An alternative for these patients is the induction of immune tolerance by cell therapy with dendritic cells pulsed with the allergen. This study aimed to evaluate the effect of myeloid dendritic cells sensitized in vitro with B. tropicalis extract in a murine model of respiratory allergy. In experimental models of respiratory allergy, T helper cells (Th2) produce allergen-specific cytokines which regulate the synthesis of allergen-specific IgE antibodies and control eosinophilic inflammation and tissue remodeling of the airways, these parameters were evaluated in this study. Tolerogenic dendritic cells from A / J mice were obtained in the presence of GM-CSF and dexamethasone and were characterized by low MHC-II expression and costimulatory molecules, marked reduction of PD-L2 and antiinflammatory profile of cytokine production. Prior inoculation of sensitized dendritic cells with Blomiasignificantly and specifically reduced the total number of leukocytes and eosinophils in the bronchoalveolar lavage fluid and reduces IgE production compared to inoculation with cells sensitized with ovalbumin, and these effects were improved with a second inoculation of tolerogenic cells. Furthermore, reducing the pulmonary inflammatory infiltrate was seen in animals that had been treated with dendritic cells regardless of the antigen used for sensitization. These results indicate that dendritic cells generated as described here can inhibit an allergic Th2 response. The specificity of the treatment, however, should be examined.