TABLE 6.
Immunogen | Dose (µg)/mouse |
Adjuvant | Homologous P9-17 |
Heterologous FA1090 |
||
---|---|---|---|---|---|---|
Geometric mean ELISA titer × 103 reciprocal (95% confidence limits) |
hSBA titer | Geometric mean ELISA titer × 103 reciprocal (95% confidence limits) |
hSBA titer | |||
P9-17 OM | 3 × 1 µg | Saline | 367 (26, 5102) | 1,024 | 47 (23, 97) | 1,024 |
3 × 10 µg | Saline | 581 (40, 8466) | 4,096 | 63 (27, 146) | 2,048 | |
3 × 1 µg | Al(OH)3 | 221 (129, 379) | 1,024 | 33 (15, 71) | 256 | |
3 × 10 µg | Al(OH)3 | 52 (18, 149) | 2,048 | 164 (59, 458) | 1,024 | |
P9-17 NaDOC-OM | 3 × 1 µg | Saline | 3 (0.3, 27) | 256–512 | 1 (0.3, 4) | 256 |
3 × 10 µg | Saline | 112 (30, 421) | 256–1,024 | 10 (2, 39) | 256 | |
3 × 1 µg | Al(OH)3 | 12 (2, 71) | 256 | 18 (4, 74) | 256 | |
3 × 10 µg | Al(OH)3 | 22 (8, 66) | 256 | 108 (25, 466) | 256 | |
None | No antigen dose | Saline | No reactivity | 16–32 | No reactivity | 16 |
No antigen dose | Al(OH)3 | No reactivity | 16 | No reactivity | 4 |
Murine antisera were tested individually in solid-phase ELISA against the homologous immunizing P9-17 OM and against a heterologous FA1090 OM preparation. Data represent the geometric means of the reciprocal ELISA titers (× 103) of n = 5 animals per immunization group, with the 95% confidence limits in parentheses. Sham-immunized animals showed no reactivity in ELISA against the OM preparations (the absorbance at λ450 nm of antisera tested at a starting dilution of 1/100 was <0.1; i.e., the level was similar to that measured for the no-serum background controls). Pooled antisera raised to P9-17 OM and NaDOC-OM and corresponding sham-immunized control sera were tested for their ability to induce complement-mediated killing of homologous N. gonorrhoeae strain P9-17 (homologous allele 10-encoded Ng-ACP) and FA1090 (heterologous allele 6-encoded Ng-ACP), using an hSBA. The data presented represent the reciprocals of the highest serum dilution at which ≥50% killing was observed. No killing was observed with any of the antisera tested with normal human serum that had been decomplemented by heat inactivation (titers of <4). The titers are expressed as the median values from two or more independent experiments.