OBJECTIVES: Neutrophils play an important role in the control of pathogens through several mechanisms, including phagocytosis and the formation of neutrophil extracellular traps (NETs). The latter consists of DNA as a backbone with embedded antimicrobial peptides, histones, and proteases, providing a matrix to entrap and in some cases to kill microbes. Some metabolic requirements for NET formation have recently been described. The virus-induced formation of NETs and the role of these traps in viral infections remain scarcely reported. Here, we analyzed whether dengue virus serotype-2 (DENV-2) induces NET formation and the DENV-2 effect on phorbol myristate acetate (PMA)-induced NETs. METHODS: Peripheral blood-derived neutrophils were exposed in vitro to DENV-2 or exposed to DENV-2 and then stimulated with PMA. NET formation was assessed by fluorescence microscopy. Cell membrane Glut-1, glucose uptake, and reactive oxygen species (ROS) production were assessed. RESULTS: DENV-2 does not induce the formation of NETs. Moreover, DENV-2 inhibits PMA-induced formation of NETs by about 80%. This effect is not related to the production of ROS. The mechanism seemingly accountable for this inhibitory effect is the DENV-2-mediated inhibition of PMA-induced glucose uptake by neutrophils. CONCLUSION: Our results suggest that DENV-2 inhibits glucose uptake as a metabolism-based way to avoid the formation of NETs.
OBJECTIVES: Neutrophils play an important role in the control of pathogens through several mechanisms, including phagocytosis and the formation of neutrophil extracellular traps (NETs). The latter consists of DNA as a backbone with embedded antimicrobial peptides, histones, and proteases, providing a matrix to entrap and in some cases to kill microbes. Some metabolic requirements for NET formation have recently been described. The virus-induced formation of NETs and the role of these traps in viral infections remain scarcely reported. Here, we analyzed whether dengue virus serotype-2 (DENV-2) induces NET formation and the DENV-2 effect on phorbol myristate acetate (PMA)-induced NETs. METHODS: Peripheral blood-derived neutrophils were exposed in vitro to DENV-2 or exposed to DENV-2 and then stimulated with PMA. NET formation was assessed by fluorescence microscopy. Cell membrane Glut-1, glucose uptake, and reactive oxygen species (ROS) production were assessed. RESULTS: DENV-2 does not induce the formation of NETs. Moreover, DENV-2 inhibits PMA-induced formation of NETs by about 80%. This effect is not related to the production of ROS. The mechanism seemingly accountable for this inhibitory effect is the DENV-2-mediated inhibition of PMA-induced glucose uptake by neutrophils. CONCLUSION: Our results suggest that DENV-2 inhibits glucose uptake as a metabolism-based way to avoid the formation of NETs.
Authors: Sharon de T Martins; Diogo Kuczera; Jan Lötvall; Juliano Bordignon; Lysangela R Alves Journal: Front Microbiol Date: 2018-08-06 Impact factor: 5.640
Authors: María Maximina B Moreno-Altamirano; Simon E Kolstoe; Francisco Javier Sánchez-García Journal: Front Cell Infect Microbiol Date: 2019-04-18 Impact factor: 5.293
Authors: Carlos H Hiroki; Juliana E Toller-Kawahisa; Marcilio J Fumagalli; David F Colon; Luiz T M Figueiredo; Bendito A L D Fonseca; Rafael F O Franca; Fernando Q Cunha Journal: Front Immunol Date: 2020-01-31 Impact factor: 7.561