Table 3.
Proteins and peptides utilized as recall antigens for ELISpot analysis of splenocytes obtained after delivery of MVA vaccines that encoded NP, M2 or M2e. p values were calculated by t-test, 2-tailed, equal variance. Influenza recall antigens were derived from proteins of H1N1 PR8 INFV A.
| Statistical Difference Compared to Medium |
Recall Antigen | Antigen | MHC Class | Spots Per 300,000 Cells |
|---|---|---|---|---|
| Medium | None | None | 3 ± 2 | |
| p < 0.001 | NP (H1N1) protein | NP | NA 1 | 98 ± 56 |
| p < 0.001 | TYQRTRALV peptide | NP | I | 325 ± 126 |
| p < 0.001 | RLIQNSLTIERMVLS peptide | NP | II | 53 ± 31 |
| None | M2 protein (H1N1 PR8) | M2 | NA 1 | 11 ± 17 |
| None | IAANIIGIL peptide 2 | M2 | I | 7 ± 11 |
| None | IYRRFKYGL peptide 2 | M2 | I | 3 ± 2 |
| None | LLTEVETPI peptide | M2e | I | 7 ± 11 |
| p < 0.001 | VETPIRNEW peptide | M2e | I | 38 ± 18 |
| p < 0.001 | SLLTEVETPIRNEWGCRCNGSSD peptide | M2e | II | 26 ± 18 |
| NA 3 | SPGAAGWDL and VGPSNSPTF | MVA | I | 666 ± 71 |
1 Not applicable, recall antigen was whole-molecule protein. 2 Peptides IAANIIGIL and IYRRFKYGL are within the internal domains of the M2 molecule, and are not found within the external M2e domain, therefore were not contained within the vaccines tested. These low and high scoring (respectively) epitope peptides [28] are negative controls. 3 Not applicable. MVA MHC class I peptides [29] were system suitability standards.