TRANSFORMING GROWTH FACTOR-BETA MODULATION OF HUMAN NEUTROPHIL EXTRACELLULAR TRAPS (NET) FORMATION INDUCED BY RESPIRATORY SYNCYTIAL VIRUS

GEFFNER, JORGE RAÚL; BAUMEISTER, ELSA; KEITELMAN, IRENE; TREVANI, ANALÍA SILVINA; RUSSO, MARA; FUENTES, FEDERICO; SABBIONE, FLORENCIA; ERRA DIAZ, FERNANDO; PONTORIERO, ANDREA; SHIROMIZU, CAROLINA MAIUMI

CABA

Congreso; LXV ANNUAL MEETING OF ARGENTINE SOCIETY OF IMMUNOLOGY; 2017

Respiratory syncytial virus (RSV) infection is the leading cause ofbronchiolitis and hospitalization in young infants and is responsiblefor almost 200000 deaths annually. Previous studies indicated thatRSV induces NET formation and these NET capture RSV virionsand prevent viral binding and infection of A549 epithelial cells. Additionalstudies showed that RSV triggers TGF-β production fromlung epithelial cells and macrophages, and TGF-β facilitates RSVinfection of epithelial cells. Here we aim to: 1) confirm the abilityof supernatants of RSV-infected-epithelial cells, the usual sourceof virus, to induce NET, discriminating the contribution of mediatorsreleased by epithelial cells (ECS); 2) determine the ability of TGF-bto modulate RSV-induced NETosis; and 3) evaluate the ability ofRSV-induced NET (NET-RSV) to promote the release of proinflammatorycytokines by 16HBE14o- bronchial epithelial cells. NETosiswas evaluated with human neutrophils by determining the DNAconcentrations in culture supernatants and by confocal microscopy.RSV (101 PFU/ml) induced NETosis in contrast to ECS employedat the same dilution (p