SAFETY AND IMMUNOGENICITY OF A PSEUDOMONAS-AERUGINOSA OUTER-MEMBRANE PROTEIN-I VACCINE IN HUMAN VOLUNTEERS

The outer membrane protein I (OprI) of Pseudomonas aeruginosa was expr essed in Escherichia coli and purified by Ni2+ chelate-affinity chroma tography. After safety and pyrogenicity evaluation in animals, four gr oups of seven adult human volunteers were vaccinated three times at fo ur week intervals with either 500 mu g, 200 mu g, 50 mu g or 20 mu g o f OprI adsorbed onto Al(OH)(3). All vaccinations were well tolerated a nd no systemic side effects were detected. A significant rise of antib ody titers against OprI could be measured in the serum of all voluntee rs who had received the 500 mu g, 200 mu g or 50 mu g doses. Elevated antibody titers against OprI could still be measured 30 weeks after th e final vaccination. Binding of the complement component Clq to the el icited antibodies could be demonstrated, showing the ability of the la tter to promote antibody-mediated complement-dependent opsonization. C opyright (C) 1996 Elsevier Science Ltd.