TABLE 3.

Ebola virus protein sequences recognized by murine CD8+ T cellsa

EBOV proteinEpitope sequenceAmino acid positionRestrictionResult of indicated assaySurvivale
IFN-γ ICCbIFN-γ ELISPOTc51Crd
GPVSTGTGPGAGDFAFHK141-155H-2d0.24/0.02ND4710/10
WIPYFGPAAEGIYTE531-545H-2b0.4/0.0871530/50
NPVYQVNNLEEIC44-52H-2b1.06/0.114107310/10
GQFLSFASL148-156H-2b0.88/0.112954519/20
SFKAALSSL279-287H-2b0.63/0.04ND4317/18
DAVLYYHMM663-671H-2b0.99/0.119105717/20
VP24KFINKLDALH159-168H-2d0.52/0.095354620/20
NYNGLLSSI171-179H-2d0.38/0.091355120/20
PGPAKFSLL214-222H-2d3.34/0.099574318/20
VP30KFSKSQLSLLCETHLR181-196H-2d0.12/0.3ND5518/20
181-196H-2b0.45/0.151904719/20
DLQSLIMFITAFLNI231-245H-2b0.7/0.151653215/20
231-245H-2d0.42/0.17ND3816/20
VP35CDIENNPGL45-53H-2b1.99/0.15408019/20
MVAKYDHL138-145H-2b1.63/0.152497920/20
TVPQSVREAFNNL190-202H-2d0.62/0.23ND4318/20
RNIMYDHL225-323H-2b1.53/0.152028719/20
PGFGTAFHQLVQVICK233-248H-2d0.63/0.23ND4717/20
VP40LRIGNQAFLQEFVLPP150-165H-2b0.7/0.051015319/20
AFLQEFVLPPVQLPQ160-175H-2d0.45/0.22ND4717/20
YFTFDLTALK171-180H-2d0.41/0.22ND3816/20
TESPEKIQAI232-141H-2d0.6/0.22ND3718/20
Lassa NRPLSAGVYMGNLSSQH-2b1.5/0.144250/20
H-2d0.7/0.183250/10
MLRH-2b0/40
H-2d0/20
PBSH-2b0/20
H-2d0/20
  • a Mice were vaccinated with 2.0 × 106 IU of VRP expressing Ebola virus GP, NP, VP24, VP30, VP35, or VP40. On day 28, mice were given a booster, and 7 days later, splenocytes were collected. In some cases (GP, VP35, VP30, and VP40 in BALB/c mice [H-2d]) mice received multiple booster vaccinations or larger doses of vaccine before sequences containing potential epitopes were identified.

  • b Splenocytes were used ex vivo for identification of peptides that induced IFN-γ-expressing CD8+ T cells. Data shown represent intracellular IFN-γ data after 5 h of restimulation with peptide. The data are expressed as follows: percentage of peptide-induced IFN-γ-positive/percentage of background IFN-γ-positive cells.

  • c Data are expressed as numbers of spot-forming cells per 106 peripheral blood mononuclear cells in the IFN-γ ELISPOT assay. Representative data are shown for one experiment. ND, not detected in assay.

  • d Data are expressed as percent specific lysis in a chromium release assay with haplotype-matched, peptide-pulsed targets at a 25:1 effector:target ratio, except for the GP107 peptide, which is the specific lysis at a 33:1 ratio.

  • e Data are expressed as numbers of mice surviving challenge/number tested. Peptide-specific restimulated lymphocytes were adoptively transferred to filovirus-naïve mice approximately 4 h before mice were challenged with 1,000 PFU of mouse-adapted Ebola virus. Control mice received PBS, or 5 × 106 cells from a mixed-lymphocyte reaction culture or 5 × 106 Lassa N-specific CTLs. No clinical symptoms were observed in any surviving mice.