INFLUENCE OF THE INTESTINAL ENVIRONMENT ON ESCHERICHIA COLI O157:H7 PATHOGENICITY AND INFECTIVITY

BERNAL AM; FERNÁNDEZ-BRANDO RJ; GIRARDI JI; RAMOS MV; ERREA A; RUMBO M; PALERMO MS

Congreso; Reunion Anual de Sociedades de Biociencias SAIC. SAI. SAFIS 2020; 2020

We previously demonstrated a different outcome post E. coliO157:H7 (O157) infection between weaned C57BL and BALB mice.Although bacterial burden is similar, C57BL show increased tissuedamage and mortality. The aim of this work is to investigate howintestinal environment affects pathogen virulence and horizontaltransmission in both strains.3 days post infection (pi), we analyzed the Stx production of recovered O157 from C57BL and BALB feces. Results showed similar Stxproduction by VERO and ELISA assays. Besides, we determinedthe 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