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Matured in the thymus, γδT cells can modulate the development of allergy in humans. The main γδT cell subsets have been described as interleukin (IL)-17A or interferon (IFN)-γ producers, but these cells can also produce other modulatory cytokines, such as IL-4 and IL-10. Here, we aimed to evaluate whether IgG can modulate the profile of cytokine production by γδT cells during their maturation in the thymus and after its migration to peripheral tissues. Thymic tissues were obtained from 12 infants, and peripheral blood mononuclear cells (PBMCs) were obtained from adults (both groups without an atopic background). IgG was purified from atopic and non-atopic volunteers. Thymocytes and PBMCs were cultured with purified atopic or non-atopic IgG, and intracellular cytokine production and phenotype were assessed. Mock and IVIg conditions were used as controls. IgG from non-atopic individuals induced IFN-γ and IL-10 production by thymic γδT cells, and no effect was observed on peripheral γδT cells. IL-17 production was inhibited by non-atopic IgG on thymic γδT cells and augmented by atopic IgG on peripheral γδT cells. Modulated thymic γδT cells did not produce IFN-γ and IL-10 simultaneously. We additionally evaluated the phenotype of intrathymic γδT cells and observed that IgG from all groups could induce CD25 expression and could not influence the CD28 expression of these cells. This report describes evidence revealing that IgG may influence the production of IFN-γ and IL-10 by intrathymic γδT cells depending on the donor atopic state. This observation is unprecedented and needs to be considered in further studies in the IgG immunotherapy field.

The regulation of offspring allergy development mediated by maternal immunization was evidenced by several groups, and this mechanism seems to involve the induction of regulatory T cells (Tregs) on offspring. Here, we aimed to evaluate whether the effect of maternal immunization on offspring Tregs occurs as a result of peripheral or central modulation. Briefly, C57BL/6 female mice were immunized with OVA in Alum or Alum alone and boosted with OVA in saline or saline only after 10 and 20 days. Non-immunized offspring serum, thymus and spleen were evaluated at 3 or 20 days old, and some groups of pups were submitted to neonatal OVA-immunization protocol for the subsequent evaluation of antibody production and allergic response. Our experimental protocol could be validated because maternal OVA-immunization inhibited offspring allergic response as evidenced by the suppression of offspring IgE production and allergic lung inflammation. Interestingly, maternal immunization reduced the frequency of offspring thymic Tregs with an opposite effect on spleen Tregs. Furthermore, after neonatal immunization, the frequency of lung-infiltrated Tregs was also augmented on offspring from immunized mothers. In conclusion, maternal OVA-immunization can inhibit the thymic maturation of offspring Tregs without implications on peripheral Tregs induction and allergy inhibition.

A Baixada Santista encontra-se na região central do litoral de São Paulo (23o55S). É um típico ambiente costeiro tropical dominado por extensos manguezais. Entretanto, vem sofrendo intenso processo de alteração ambiental devido a atividades industriais e portuárias, além da ausência de planejamento urbano. A fim de avaliar a capacidade de recomposição natural dos manguezais na Ilha Barnabé foram realizados estudos em bosque impactado por derramamento e combustão de produto químico (DCPD) em 1998, monitorando a recomposição natural da vegetação (2002-2007); a produção de serapilheira (2002-2007) e a microtopografia (2004 e 2008). Também foram analisadas fotografias aéreas em escala multitemporal (1962, 1972, 1994 e 2003) e a caracterização estrutural de bosques em diferentes estágios sucessionais. No bosque impactado por produto químico, a recomposição natural se mostrou eficaz, porém lenta; a produção de serapilheira apresentou valores crescentes ao longo dos anos com grande contribuição de propágulos deformados ou abortados e a microtopografia mostrou intensa dinâmica sedimentar. A análise das fotografias aéreas mostrou os diversos impactos ocorridos na região com formação de clareiras na vegetação e recomposição natural parcial. A caracterização estrutural dos bosques em diferentes estágios sucessionais mostrou que a recomposição natural dos manguezais da Ilha Barnabé apresenta um mosaico de características estruturais refletindo as diferentes intensidades e tipos de tensores que atuam na região. A metodologia utilizada mostrou-se adequada para avaliação da capacidade de recomposição natural de bosques de mangue. The Baixada Santista and Santos Estuary are located in the central portion of the São Paulo State coastline (23º55\'S). It is a typical tropical coastal environment dominated by extensive mangroves areas despite the intensive harbor and heavy industrial activities, and their location within a continually evolving human landscape. The present study was developed in a mangrove area at Barnabé Island. In order to assess the natural recovery of the mangroves, a site impacted in 1998 by a DCPD (dicyclopentadiene) spill that was followed by a fire, natural recovery, litter fall and microtopography was monitored (2002-2008). Also was an analysed aerial photograph at Barnabé Island in multitemporal scale (1962, 1972, 1994 and 2003) and realized structural characterization in different successional stages mangroves stands. In a site impacted by a DCPD the recovery was successful but very low; in litter fall the values increasing in period and was observed propagule deformities and a intense sedimentary dynamics. The aerial photographs showed different impacts with gap creation and partial recovery process in some areas. Structural characterization in different successional stages mangroves stands showed zonation that reflects a gradient of stress. The methodology used appears adequate to describe and assess the capacity of natural recovery mangrove stands.