Detection of IgG Antibodies to Type-Specific Pseudomonas aeruginosa Lipopolysaccharides by Solid-Phase Radioimmunoassay

Previous studies have suggested that IgG serotype-specific antibodies are protective against infections with pseudomonas aeruginosa. In the present study, type-specific IgG antibodies to P. aeruginosa were detected by solid-phase radioimmunoassay in sera from 15 volunteers before and after vaccination with lipopolysaccharides from P. aeruginosa and from four patients with endocarditis due to P. aeruginosa. Significant type-specific increases in IgG antibody occurred after both vaccination and infection. The correlation coefficients comparing net counts per minute by solid-phase radioimmunoassay with hemagglutination titers in the 15 vaccinees were 0.940, 0.874, 0.792, 0.903, 0.882, 0.869, and 0.704 for serotypes 1--7, respectively.