JOSENILSON FEITOSA DE LIMA
Projetos de Pesquisa
Unidades Organizacionais
LIM/56 - Laboratório de Investigação em Dermatologia e Imunodeficiências, Hospital das Clínicas, Faculdade de Medicina
4 resultados
Resultados de Busca
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- Staphylococcal enterotoxins modulate the effector CD4(+)T cell response by reshaping the gene expression profile in adults with atopic dermatitis(2019) ORFALI, Raquel Leao; YOSHIKAWA, Fabio Seiti Yamada; OLIVEIRA, Luanda Mara da Silva; PEREIRA, Natalli Zanete; LIMA, Josenilson Feitosa de; RAMOS, Yasmim Alefe Leuzzi; DUARTE, Alberto Jose da Silva; SATO, Maria Notomi; AOKI, ValeriaStaphylococcus aureus colonizes the skin of atopic dermatitis (AD) individuals, but the impact of its enterotoxins on the chronic activation of CD4(+)T cells demands further analysis. We aimed to analyze the CD4(+)T cell anergy profile and their phenotypic and functional features through differential expression of cellular activation markers, cytokine production and response to staphylococcal enterotoxin A (SEA). A panel of 84 genes relevant to T cell anergy was assessed by PCR array in FACS-sorted CD4(+)T cells, and the most prominent genes were validated by RT-qPCR. We evaluated frequencies of circulating CD4(+)T cells secreting single or multiple (polyfunctional) cytokines (IL-17A, IL-22, TNF, IFN-gamma, and MIP-1 beta) and expression of activation marker CD38 in response to SEA stimulation by flow cytometry. Our main findings indicated upregulation of anergy-related genes (EGR2 and IL13) promoted by SEA in AD patients, associated to a compromised polyfunctional response particularly in CD4(+)CD38(+)T cells in response to antigen stimulation. The pathogenic role of staphylococcal enterotoxins in adult AD can be explained by their ability to downmodulate the activated effector T cell response, altering gene expression profile such as EGR2 induction, and may contribute to negative regulation of polyfunctional CD4(+)T cells in these patients.
- Proinflammatory profile of neonatal monocytes induced by microbial ligands is downmodulated by histamine(2019) BRANCO, Anna Claudia Calvielli Castelo; PEREIRA, Natalli Zanete; YOSHIKAWA, Fabio Seiti Yamada; OLIVEIRA, Luanda Mara da Silva; TEIXEIRA, Franciane Mouradian Emidio; OLIVEIRA, Luana de Mendonca; PIETROBON, Anna Julia; TORREALBA, Marina Passos; LIMA, Josenilson Feitosa de; DUARTE, Alberto Jose da Silva; SATO, Maria NotomiAlthough the neonatal period is characterized by relative immunological immaturity, an inflammatory response due to Toll-like receptor (TLR) activation is observed. Histamine may be one of the factors playing a role in restraining inflammation during the early stages of life. Therefore, we evaluated the responsiveness of human cord blood cells to TLR4 agonists and the immunomodulatory function of histamine in the inflammatory response. Compared with adults, mononuclear cells (MNCs) from newborns (NBs) exhibit impaired production of IFN-gamma-inducible chemokines, such as CXCL10 and CXCL9, upon lipopolysaccharide (LPS) stimulation. Notably, LPS induced a 5-fold increase in CCL2 secretion in NBs. Evaluation of the effect of histamine on LPS-induced CCL2 secretion showed an inhibitory effect in the majority of adults, whereas this effect was detectable in all NBs. Histamine receptor (HR) blockage revealed partial involvement of H1R, H2R and H4R in LPS-induced CCL2 inhibition in MNCs from both NBs and adults. As monocytes are the main type of mononuclear cell that produces CCL2, we evaluated genes related to TLR signaling upon LPS stimulation. Monocytes from NBs showed up-regulation of genes associated with JAK/STAT/NF-kappa B and IFN signaling. Some differentially expressed genes encoding proinflammatory factors were preferentially detected in LPS-activated monocytes from NBs, and markedly down-regulated by histamine. The immunomodulatory role of histamine on CCL2 and CXCL8 was detected at the transcript and protein levels. Our findings show that NBs have enhanced CCL2 responsiveness to LPS, and that histamine acts in immune homeostasis during the neonatal period to counterbalance the robustness of TLR stimulation.
- Exploring the Role of Staphylococcus Aureus Toxins in Atopic Dermatitis(2019) YOSHIKAWA, Fabio Seiti Yamada; LIMA, Josenilson Feitosa de; SATO, Maria Notomi; RAMOS, Yasmin Alefe Leuzzi; AOKI, Valeria; ORFALI, Raquel LeaoAtopic dermatitis (AD) is a chronic and inflammatory skin disease with intense pruritus and xerosis. AD pathogenesis is multifactorial, involving genetic, environmental, and immunological factors, including the participation of Staphylococcus aureus. This bacterium colonizes up to 30-100% of AD skin and its virulence factors are responsible for its pathogenicity and antimicrobial survival. This is a concise review of S. aureus superantigen-activated signaling pathways, highlighting their involvement in AD pathogenesis, with an emphasis on skin barrier disruption, innate and adaptive immunity dysfunction, and microbiome alterations. A better understanding of the combined mechanisms of AD pathogenesis may enhance the development of future targeted therapies for this complex disease.
- 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