TABLE 3.
Neutralization of homologous SF162 isolate
| Group | Animal | IC50a | % Reduction in neutralization |
||
|---|---|---|---|---|---|
| V1b | V3 | D368R | |||
| A (SF162/YU2 V1 gp140) | 2071 | 519 ± 182 | 0.0 ± 0.0 | 27.2 ± 2.9 | 55.0 ± 2.1 |
| 2072 | 4,025 ± 435 | 0.0 ± 0.0 | 62.9 ± 0.0 | 89.3 ± 2.1 | |
| 2073 | 1,071 ± 410 | 0.0 ± 0.0 | 49.3 ± 6.4 | 95.0 ± 0.7 | |
| 2074 | 2,218 ± 609 | 0.0 ± 0.0 | 77.9 ± 0.8 | 100.0 ± 0.0 | |
| Avgc | 1,958 (P = 0.0286)d | 0.0 | 54.3 | 84.8 | |
| B (SF162/JRFL V1 gp140) | 2075 | 1,262 ± 510 | 0.0 ± 0.0 | 40.7 ± 3.6 | 75.0 ± 16.4 |
| 2076 | 466 ± 71 | 0.0 ± 0.0 | 42.9 ± 0.0 | 56.2 ± 11.3 | |
| 2077 | 279 ± 0 | 0.0 ± 0.0 | 20.7 ± 3.6 | 9.5 ± 7.6 | |
| 2078 | 424 ± 26 | 0.0 ± 0.0 | 40.0 ± 0.0 | 53.8 ± 1.3 | |
| Avg | 608 (P = 0.0286) | 0.0 | 36.1 | 48.6 | |
| C (SF162/89.6 V1 gp140) | 2079 | 1,128 ± 214 | 0.0 ± 0.0 | 25.0 ± 0.7 | 38.6 ± 4.3 |
| 2080 | 46,306 ± 7,610 | 0.0 ± 0.0 | 67.9 ± 3.6 | 100.0 ± 0.0 | |
| 2081 | 9,328 ± 1,573 | 0.0 ± 0.0 | 57.9 ± 2.1 | 81.4 ± 10.1 | |
| 2082 | 2,035 ± 429 | 0.0 ± 0.0 | 50.7 ± 6.4 | 88.6 ± 5.7 | |
| Avg | 14,699 (P = 0.1143) | 0.0 | 50.4 | 77.1 | |
| D (SF162/HxB2 V1 gp140) | 2083 | — | — | — | — |
| 2084 | 815 ± 31 | 0.0 ± 0.0 | 26.4 ± 5.0 | 40.8 ± 10.8 | |
| 2085 | 506 ± 149 | 6.5 ± 2.2 | 0.0 ± 0.0 | 27.2 ± 2.9 | |
| 2086 | 903 ± 129 | 8.6 ± 2.9 | 49.3 ± 0.7 | 95.0 ± 5.0 | |
| Avg | 741 (P = 0.0571) | 5.0 | 25.2 | 54.3 | |
| E (V1 scaffold cocktail) | 2059 | 5,394 ± 575 | 0.0 ± 0.0 | 42.2 ± 2.1 | 87.2 ± 5.8 |
| 2060 | 2,278 ± 701 | 0.0 ± 0.0 | 27.9 ± 2.1 | 77.9 ± 6.5 | |
| 2061 | 1,303 ± 243 | 5.7 ± 0.0 | 32.9 ± 2.8 | 71.4 ± 4.3 | |
| 2062 | 1,291 ± 119 | 0.0 ± 0.0 | 30.7 ± 3.6 | 67.1 ± 0.0 | |
| Avg | 2,566 (P = 0.0286) | 1.4 | 33.4 | 75.9 | |
| F (ΔV1SF162 gp140) | 1918 | 1,773 ± 538 | 0.0 ± 0.0 | 73.6 ± 22.2 | 78.1 ± 10.6 |
| 1919 | — | — | — | — | |
| 1920 | 19,281 ± 6,180 | 0.0 ± 0.0 | 53.6 ± 2.2 | 95.0 ± 2.1 | |
| 1921 | 2,017 ± 170 | 0.0 ± 0.0 | 20.0 ± 11.2 | 96.4 ± 0.7 | |
| Avg | 7,690 (P = 0.1143) | 0.0 | 49.1 | 89.8 | |
| G (SF162 gp140) | 1914 | 56,407 ± 152 | 33.6 ± 5.0 | 2.2 ± 2.2 | 100.0 ± 0.0 |
| 1915 | 12,932 ± 6,972 | 0.0 ± 0.0 | 4.3 ± 4.3 | 100.0 ± 0.0 | |
| 1916 | 86,672 ± 6,435 | 67.9 ± 0.8 | 3.6 ± 3.6 | 100.0 ± 0.0 | |
| 1917 | 20,041 ± 926 | 12.2 ± 2.2 | 13.4 ± 0.7 | 97.2 ± 2.8 | |
| Avg | 44,013 | 28.4 | 5.9 | 99.3 | |
Plasma was collected at 2 weeks following the second gp140 immunization. The values represent the averages and standard deviations of results from two or three independent experiments performed in duplicate. —, plasma did not neutralize the isolate above 50% at lowest plasma dilution tested (1:20).
The SF162 V1 peptide was used for competitions with group F and G plasmas. The YU2, JRFL, 89.6, and HxB2 V1 peptides were used for group A to D plasma competitions, respectively. A combination of all four heterologous V1 peptides was used to compete out group E plasma.
Average group values include only animals that neutralized virus to 50% inhibition levels.
Statistical P values, comparing IC50 titers for each group with those for group G (SF162 gp140).