PASSIVE-IMMUNIZATION WITH MONOCLONAL-ANTIBODIES SPECIFIC FOR LIPOPOLYSACCHARIDE (LPS) O-SIDE CHAIN PROTECTS MICE AGAINST INTRAVENOUS YERSINIA-ENTEROCOLITICA SEROTYPE O-3 INFECTION

Passive immunization with monoclonal antibodies specific for the lipop olysaccharide (LPS) O-side chain protected mice against intravenously given lethal doses of Yersinia enterocolitica O:3 bacteria. On the oth er hand, passive immunization with monoclonal antibody specific for th e LPS core oligosaccharide did not protect mice. Neither antibody was able to protect mice against orally given lethal doses of bacteria. Th ese results indicate that the O-side chain functions as an important a ntigenic structure during infection, and that immunity to it probably offers protection also in the in vivo situation.