Gene-Specific Countermeasures against Ebola Virus Based on Antisense Phosphorodiamidate Morpholino Oligomers
Figure 4
Immune Responses of PMO-Treated Mice Following Survival of Ebola Virus Infection
(A) PMO-treated C57BL/6 mice that have previously survived EBOV infection generate EBOV-specific CD8+ responses. Pooled splenocytes from three PMO-treated EBOV survivors were restimulated in vitro with EBOV-specific VP35 or NP peptides, an irrelevant Lassa NP peptide as a negative control, or PMA/ionomycin as a positive control. The stimulated cells were stained after for 4 h in culture with anti-CD44-FITC, anti-IFN-γ-PE, and anti-CD8-Cy-Chrome. The percent of CD44+, IFN-γ+ cells among CD8+ lymphocytes is indicated in the upper right quadrant of each plot. These data are representative of several experiments examining the EBOV-specific T cell epitopes in PMO-treated mice after challenge.
(B) Total serum anti-EBOV antibodies were measured in surviving mice prior to or 4 wk following treatment and challenge. PMO mice were treated with the combination of PMOs 24 hand 4 h before challenge, and their antibody responses are compared with mice treated with Ebola VLPs 24 h before EBOV infection. The results are depicted as the endpoint titers of the individual mice (filled circles). The horizontal line in each column represents the geometric mean titer of the group.
(C) Mice that previously survived EBOV challenge following PMO treatment were rechallenged with 1,000 pfu of mouse-adapted Ebola virus 4 wk after the initial challenge. Results are plotted as percent survival for the PMO-treated mice (black) and naïve control mice (n = 10 per group).