Comparative studies on the protective potential of antisera directed against four antigenic preparations from Pseudomonas aeruginosa

Abstract

Three subcellular fractions and a formalin-killed whole-cell vaccine were prepared from a virulent strain of Pseudomonas aeruginosa (PA-7) and tested for their ability to induce protective antisera in rabbits, as measured by passive protection afforded mice challenged with a lethal dose of viable cells 4 h after receiving an intraperitoneal injection of 0.2 ml of whole or diluted immune rabbit serum.All preparations were found to elicit antiserum capable of providing protection for mice given a challenge dose of 20 LD₅₀. The passive hemagglutinating antibody titer of a given serum appeared to be more reliable than the bacterial agglutinin level as a criterion for estimating the protective potential of the serum.