Table 2.
Summary of ELISpot responses as measured by SFC/106 peripheral blood mononuclear cells (PBMC) after stimulation with apical membrane antigen 1 (AMA-1) at 1.0 or 10.0µg/ml concentrations in semi-immune Malian adults receiving either the three-dose series of FMP2.1/AS02A (half (25µg/0.25 ml) or full (50µg/0.5 ml) dose) or the comparator RabAvert® vaccine.
| Vaccine (n) | Cytokine | AMA-1 concentration (µg) |
Spot forming cells/106 cells Day 0a |
Spot forming cells/106 cells Day 90 |
P valueb(study vs. control) |
P value (Day 0 vs. Day 90) |
|---|---|---|---|---|---|---|
| Half-dose FMP2.1/AS02A (19) | IFN-γ | 1 | 126 | 222 | ns | nsc |
| 10 | 138 | 313 | ns | 0.01 | ||
| Full dose FMP2.1/AS02A (18) | IFN-γ | 1 | 131 | 243 | ns | 0.01 |
| 10 | 182 | 378 | ns | 0.01 | ||
| Combined FMP2.1/AS02A (37) | IFN-γ | 1 | 129 | 233 | ns | 0.01 |
| 10 | 161 | 347 | ns | 0.02 | ||
| RabAvert® (19) | IFN-γ | 1 | 105 | 244 | – | 0.02 |
| 10 | 163 | 347 | – | <0.001 | ||
| Half-dose FMP2.1/AS02A (19) | IL-5 | 1 | 1.5 | 90.5 | 0.06 | 0.01 |
| 10 | 2.3 | 121.5 | 0.049 | 0.004 | ||
| Full dose FMP2.1/AS02A (18) | IL-5 | 1 | 1.6 | 38.6 | ns | 0.006 |
| 10 | 2.0 | 69.4 | ns | <0.001 | ||
| Combined FMP2.1 (37) | IL-5 | 1 | 1.5 | 63.1 | 0.08 | <0.001 |
| 10 | 2.1 | 94 | 0.029 | <0.001 | ||
| RabAvert® (19) | IL-5 | 1 | 2.1 | 25.1 | – | ns |
| 10 | 3.3 | 42.4 | – | 0.01 |
(n) = (number of volunteers).
SFC results represent mean number of spots measured per 106 PBMC plated. No statistical differences in SFC were noted between cohorts at Day 0, pre-vaccination.
Statistical analysis performed on Day 90 FMP2.1 vaccine vs. RabAvert® comparator vaccine with level of significance defined as P < 0.05. Italicized results are reported when close to the level of significance.
Not statistically significant (ns).