ROLE OF THE MICROGLIA AND INFLAMMATION IN THE ENCEPHALOPATHY PRODUCED BY SHIGA TOXIN 2 AND LIPOPOLYSACCHARIDE

PINTO ALIPIO; ROSATO-SIRI VICTORIA; ARENAS DAVID; GEOGHEGAN PATRICIA; BERDASCO CLARA; CANGELOSI ADRIANA; GOLDSTEIN JORGE

Simposio; 10th International Symposium VTEC2018; 2018

Introduction: The Central Nervous System is usually affected in patients infected with EHEC. In addition to Stx2, LPS is also released and may contribute with the observed neurologic dysfunctions. The aim of this study was to determine whether: i) Stx2 and/or LPS alters mice behavior, ii) an inflammatory event is involved, and iii) these toxins cause a microglial (MG) response. Methods: Male mice were injected systemically with either saline, Stx2, LPS, Stx2+LPS, Dexamethasone (D)+saline, D+LPS, D+Stx2 or D+Stx2+LPS. After four days of treatment the animals were subjected to behavioral forced swimming (FST), swimming (ST) and Von Frey Filament (VFT) tests, while their brain status were evaluated by immunofluorescence (IF) to reactive glial GFAP and Iba1. Also, MG primary cultures were incubated with DMEM or Stx2, under heat shock (HS) or LPS (infection features) to test by IF Stx2-cannonical uptake, MG Iba1 reactivity and Gb3 immunoexpression. Results: Stx2 increased the latency per distance in the ST and insensitivity in the VFT (2.1+/-0.25 saline vs. 2.7+/-0.30 Stx2 in s, 3.7+/-0.21 saline vs. 4.0+/-0.03 Stx2 in g, respectively), while Stx2+LPS maximally increased the immobility time in the FST (30.15+/-10.00 saline vs. 186.35+/-8.00 Stx2+LPS in s) and increased the expression levels of GFAP (48.71+/-3.80 saline vs 79.85+/-3.80 Stx2+LPS in UA) and Iba1 (11.23+/-2.30 saline vs. 27.12+/-4.75 Stx2+LPS in UA); all p