title: Interferon-γ inhibits group B Streptococcus survival within human endothelial cells.
abstract: Endothelial dysfunction is a major component of the pathophysiology of septicaemic group B Streptococcus (GBS) infections. Although cytokines have been shown to activate human umbilical vein endothelial cells (HUVECs), the capacity of interferon (IFN)-γ to enhance the microbicidal activity of HUVECs against GBS has not been studied. We report that the viability of intracellular bacteria was reduced in HUVECs activated by IFN-γ. Enhanced fusion of lysosomes with bacteria-containing vacuoles was observed by acid phosphatase and the colocalisation of Rab-5, Rab-7 and lysosomal-associated membrane protein-1 with GBS in IFN-γ-activated HUVECs. IFN-γ resulted in an enhancement of the phagosome maturation process in HUVECs, improving the capacity to control the intracellular survival of GBS.
authors.affiliation: Laboratório de Bioensaios Farmacêuticos, Faculdade de Farmácia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brasil.
authors.forename: Viviane de Oliveira Freitas
authors.initials: Vde O
authors.lastname: Lione
authors.affiliation: Departamento de Biologia Celular, Instituto de Biologia Roberto Alcântara Gomes.
authors.forename: Michelle Hanthequeste Bittencourt dos
authors.initials: MH
authors.lastname: Santos
authors.affiliation: Departamento de Biologia Celular, Instituto de Biologia Roberto Alcântara Gomes.
authors.forename: Jessica Silva Santos de
authors.initials: JS
authors.lastname: Oliveira
authors.affiliation: Disciplina de Microbiologia e Imunologia, Faculdade de Ciências Médicas, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ, Brasil.
authors.forename: Ana Luiza
authors.initials: AL
authors.lastname: Mattos-Guaraldi
authors.affiliation: Departamento de Biologia Celular, Instituto de Biologia Roberto Alcântara Gomes.
authors.forename: Prescilla Emy
authors.initials: PE
authors.lastname: Nagao
mesh_terms: D000135:Acid Phosphatase / Q000378:metabolism; D000890:Anti-Infective Agents / Q000494:pharmacology*; D001422:Bacterial Adhesion / Q000187:drug effects; D004705:Endocytosis; D061307:Human Umbilical Vein Endothelial Cells / Q000378:metabolism / Q000382:microbiology*; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology*; D008247:Lysosomes / Q000187:drug effects; D050296:Microbial Viability / Q000187:drug effects*; D010588:Phagosomes / Q000187:drug effects; D061251:Primary Cell Culture; D013290:Streptococcal Infections / Q000188:drug therapy* / Q000517:prevention & control; D013292:Streptococcus agalactiae / Q000187:drug effects*; D016019:Survival Analysis
chemical_list: D000890:Anti-Infective Agents; D007371:Interferon-gamma; D000135:Acid Phosphatase