FABIO DA RESSURREICAO SGNOTTO
Índice h a partir de 2011
8
Projetos de Pesquisa
Unidades Organizacionais
Instituto Central, Hospital das Clínicas, Faculdade de Medicina
LIM/56 - Laboratório de Investigação em Dermatologia e Imunodeficiências, Hospital das Clínicas, Faculdade de Medicina
LIM/56 - Laboratório de Investigação em Dermatologia e Imunodeficiências, Hospital das Clínicas, Faculdade de Medicina
4 resultados
Resultados de Busca
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- IgG from Non-atopic Individuals Induces In Vitro IFN-gamma and IL-10 Production by Human Intra-thymic gamma delta T Cells: A Comparison with Atopic IgG and IVIg(2019) SANTOS, Ludimila Souza; SGNOTTO, Fabio da Ressureicao; INOUE, Amanda Harumi Sabo; PADRECA, Archangelo Fernandes; MENGHINI, Ricardo Palamar; DUARTE, Alberto Jose da Silva; VICTOR, Jefferson RussoMatured in the thymus, gamma delta T cells can modulate the development of allergy in humans. The main gamma delta T cell subsets have been described as interleukin (IL)-17A or interferon (IFN)-gamma 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 gamma delta T 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-gamma and IL-10 production by thymic gamma delta T cells, and no effect was observed on peripheral gamma delta T cells. IL-17 production was inhibited by non-atopic IgG on thymic gamma delta T cells and augmented by atopic IgG on peripheral gamma delta T cells. Modulated thymic gamma delta T cells did not produce IFN-gamma and IL-10 simultaneously. We additionally evaluated the phenotype of intrathymic gamma delta T 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-gamma and IL-10 by intrathymic gamma delta T cells depending on the donor atopic state. This observation is unprecedented and needs to be considered in further studies in the IgG immunotherapy field.
- Maternal IgG impairs the maturation of offspring intrathymic IL-17-producing gamma delta T cells: Implications for murine and human allergies(2019) DE-OLIVEIRA, Marilia G.; LIRA, Aline A. L.; SGNOTTO, Fabio R.; INOUE, Amanda H. S.; SANTOS, Ludimila S.; NAKAMATSU, Bernardo Y.; DUARTE, Alberto J. S.; LEITE-DE-MORAES, Maria; VICTOR, Jefferson R.Background The precise mechanism involved in the acquisition of the IL-17+ profile of gamma delta T cells, the ligands responsible for this change, and whether this default is acquired during intrathymic maturation need to be elucidated. Objective This study aimed to evaluate whether IL-17-producing gamma delta T cells are present in the airways of tolerant offspring from allergen-sensitized mothers and the possible implication of maternal IgG in the generation of these cells. Methods Female mice were immunized or not, and the allergic response, frequency of gamma delta T cell subsets and cytokine production of the offspring were analysed by flow cytometry. The effects of passive in vivo transfer of purified IgG were investigated in offspring. A translational approach was employed to analyse gamma delta T cells in the thymus and PBMCs from humans. Results Maternal immunization reduced the frequency of spontaneous IL-17-producing gamma delta T cells in the thymus, spleen and lung of offspring. This effect was mimicked by the in vivo treatment of females with purified IgG. IgG directly interacted with gamma delta T cell membranes. The modulatory effect of human IgG on human infant intrathymic and adult peripheral gamma delta T cells showed similarities to murine gamma delta T cells, which is rarely reported in the literature. Conclusions & Clinical Relevance Together, our results reveal that IgG from potentially tolerant atopic mothers can influence offspring thymic IL-17-producing gamma delta T cell maturation. Furthermore, we suggest that IgG is an unprecedented modulatory factor of murine and human gamma delta T cells. These observations may support the future development of IgG-based immunoregulatory therapeutic strategies.
- IgG From HIV-1-Exposed Seronegative and HIV-1-Infected Subjects Differently Modulates IFN-gamma Production by Thymic T and B Cells(2019) SGNOTTO, Fabio da Ressureicao; SANTOS, Ludimila Souza; SOUSA, Thamires Rodrigues de; LIMA, Josenilson Feitosa de; OLIVEIRA, Luanda Mara da Silva; SANABANI, Sabri Saeed; DUARTE, Alberto Jose da Silva; VICTOR, Jefferson Russo
conferenceObject COMPARISON OF CELL COUNTING METHODS: STANDARD HEMATOLOGY ANALYZER VERSUS VOLUMETRIC CELL COUNTING FLOW CYTOMETRY.(2019) SGNOTTO, Fabio; SILVA, Marcal; BARROSO, Rodrigo; LOPES, Guilherme; MACIEL, Felipe; KONECSNI, Cecilia; SALES, Maria Mirtes