PRESERVATION OF PROTECTIVE EFFECTS OF HYPERIMMUNE ANTI STX2 BOVINE COLOSTRUM AGAINST EHEC O157:H7 PATHOGENICITY AFTER PASTEURIZATION AND SPRAY-DRYING PROCEDURES.

N. GARIMANO; L.I. DÍAZ VERGARA; A.D. KIM; E. E. BADIN; S. SODERO; A. M. BERNAL; D. D. GONZALEZ; M. M. AMARAL; A. R. LESPINARD; C. PORPORATTO; M. A. MONTENEGRO; M. S. PALERMO; M. LARZABAL; A.A. CATALDI; C. IBARRA; F. SACERDOTI

Buenos Aires

Congreso; REUNIÓN DE SOCIEDADES DE BIOCIENCIAS 2020; 2020

SOCIEDAD ARGENTINA DE INVESTIGACIÓN CLÍNICA (SAIC) - SOCIEDAD ARGENTINA DE INMUNOLOGÍA (SAI) - SOCIEDAD ARGENTINA DE FISIOLOGÍA (SAFIS).

Enterohaemorrhagic Escherichia coli (EHEC) O157:H7 is a majoretiologic agent responsible for bloody diarrhea, hemorrhagic colitis,and hemolytic uremic syndrome (HUS). Shiga toxin (Stx) is the mainvirulence factor of EHEC and the main responsible for the onsetof HUS. Although many efforts have been made to develop an effectivetreatment for Stx-mediated HUS, a specific therapy has notbeen found yet. It is well known that human consumption of bovinecolostrum has therapeutic effects against several gastrointestinalinfections, as it contains a range of peptides and proteins (includingantibodies) with antimicrobial and endotoxin-neutralizing effects.Consistent with these findings, we have previously demonstratedthat colostrum from Stx type 2 (Stx2)-immunized pregnant cows effectivelyprevents Stx2 cytotoxicity and EHEC O157:H7 pathogenicity.This study evaluated different pasteurization (72°C for 15 s vs60°C for 60 min) and spray drying paramenters (Inlet temperature110°C vs 120°C and outlet temperature lower or higher than 55°C)in order to optimize the preservation of the protective properties ofhyperimmune colostrum (HIC-Stx2) against Stx2 after processing.Characterization of neutralizing properties of colostrum were assayedin vitro and in vivo. Our results showed that pasteurizationat 60°C for 60 min, combined with spray-drying at inlet and outlettemperatures of 120°C and >55°C, respectively, showed the highestyield and lowest humidity on final samples (p