Hyperimmune lipopolysaccharide antiserum mediatedinhibition of the adherence of E. coli O157:H7 to HEP-2cells and large intestine of mice

Escherichia coli O157:H7 is found in cattle farms and can live in the intestine of healthy cattle. Most cases of human illnesses including nonbloody diarrhea, hemorrhagic colitis and hemolytic uremic syndromecan be traced, either directly or indirectly, to cattle. One strategy for reducing the risk of Enterohemorrhagic Escherichia coli (EHEC) infections in human is to reduce the prevalence of infection in cattle. Antiserum against whole cell of isolated E. coli O157:H7 from cattle showed inhibition of adherence of this strain toHEP-2 cells and intestine of model mice. The ability of this antiserum in blocking the attachment of bacteriato HEP-2 cells in 1:1280 titer and to intestine tissue of mice in 1:640 titer are significant. Histology of intestine tissue confirms our results. The difference between in vivo and in vitro titrations for blocking the attachment depends on these two different conditions