Transforming growth factor-beta (TGF-beta) modulation of human neutrophils extracellular traps (NET) formation induced by respiratory syncytial virus

SABBIONE, FLORENCIA; FUENTES, FEDERICO; SHIROMIZU, CAROLINA MAIUMI; RUSSO, MARA; PONTORIERO, ANDREA; JANCIC, CAROLINA C; ERRA DIAZ, FERNANDO; KEITELMAN, IRENE A; BAUMEISTER, ELSA; GEFFNER, JORGE R.; ANALÍA, TREVANI S.

CABA

Congreso; Reunión Conjunta de Sociedades de Biociencias; 2017

Respiratory syncytial virus (RSV) infection is the leading cause of bronchiolitis and hospitalization in young infants and is responsible for almost 200000 deaths annually. Previous studies indicated that RSV induces NET formation and these NET capture RSV virions and prevent viral binding and infection of A549 epithelial cells. Additional studies showed that RSV triggers TGF-beta production from lung epithelial cells and macrophages, and TGF-beta facilitates RSV infection of epithelial cells. Here we aim to: 1) confirm the ability of supernatants of RSV-infected-epithelial cells, the usual source of virus, to induce NET, discriminating the contribution of mediators released by epithelial cells (ECS); 2) determine the ability of TGF-beta to modulate RSV-induced NETosis; and 3) evaluate the ability of RSV-induced NET (NET-RSV) to promote the release of proinflammatory cytokines by 16HBE14o- bronchial epithelial cells. NETosis was evaluated with human neutrophils by determining the DNA concentrations in culture supernatants and by confocal microscopy. RSV (101 PFU/ml) induced NETosis in contrast to ECS employed at the same dilution (p