a pair of o4,5,12 and o9,12 his ( + ) sister transductants derived from a virulent salmonella typhimurium parent were used as intraperitoneal and oral challenge strains to determine whether immunity directed against the o9 and o4,5 antigenic components could be detected after immunization with heat-killed vaccines containing one or the other of these antigenic components .
C0020964
immunity
C0003320
antigenic