Influence of the intestinal environment on Escherichia coli O157:H7 pathogenicity and infectivity

ALAN MAURO BERNAL; ROMINA JIMENA FERNÁNDEZ-BRANDO; JUAN IGNACIO GIRARDI; MARÍA VICTORIA RAMOS; AGUSTINA ERREA; MARTÍN RUMBO; MARINA SANDRA PALERMO

Congreso; Reunión Anual de Sociedades de Biociencias (SAIC-SAI-SAFIS) 2020; 2020

We previously demonstrated a different outcome post E. coli O157:H7 (O157) infection between weaned C57BL and BALB mice. Although bacterial burden is similar, C57BL show increased tissue damage and mortality. The aim of this work is to investigate how intestinal environment affects pathogen virulence and horizontal transmission in both strains. 3 days post infection (pi), we analyzed the Stx production of recovered O157 from C57BL and BALB feces. Results showed similar Stx production by VERO and ELISA assays. Besides, we determined the inflammatory activity of feces through a LPS-dependent HekBlue-hTLR4 reporter line assay. Feces from C57BL showed inflammatory activity at day 1, 2 and 3 pi (p