ENTEROHEMORRHAGIC Escherichia coli O157:H7 STIMULATES HUMAN NEUTROPHILS TO RELEASE NEUTROPHIL EXTRACELLULAR TRAPS (NETS)

SABBIONE F; MAIUMI SHIROMIZU C1; KEITELMAN I; BRUBALLA A; MIGLIO RODRÍGUEZ M; FUENTES F; GALLETTI J; RAMOS MV; JANCIC C; PALERMO M; TREVANI A

Tucumán

Congreso; LXVII Reunión Anual de la Sociedad Argentina de Inmunología; 2019

Shiga toxin (Stx)-producing Escherichia coli (STEC) can cause diarrhea, hemorrhagic colitis andhemolytic uremic syndrome (HUS). These non-invasive bacteria colonize the intestine wherethey release Stx, which after reaching the bloodstream causes the events of the HUS.Neutrophilia and neutrophil infiltration of gastrointestinal tissues are found in these patients.We previously demonstrated that Stx induces NETosis. Our aim was to determine if in responseto STEC neutrophils also release NETs, which in the gut might contribute to bacterialentrapment and killing but also to increase inflammation.We isolated human blood neutrophils and co-cultured them without or with E.coli O157:H7(E.coli Stx+) or with the isogenic strain incapable to produce Stx (E.coli Stx-) at MOI 1 or 10. Byimmunostaining and confocal microscopy we determined that both strains stimulated therelease of DNA which colocalized with myeloperoxidase (MPO) (n=3). DNA and MPO levelswere significantly higher than the basal condition when neutrophils were stimulated with bothbacterial strains (DNA n=6, p