A DNA Vaccine Encoding the Gn Ectodomain of Rift Valley Fever Virus Protects Mice via a Humoral Response Decreased by DEC205 Targeting

In conclusion, pscDEC-eGn and pscDEC-mCherry express functional fusion proteins able to specifically bind the murine DEC205 receptor. Targeting eGn to DEC205 Decreased the Anti-eGn IgG Responses in DNA Vaccination in Mice In order to assess whether targeting eGn to DEC205 would promote the anti-eGn IgG response in mice whereas it did not in sheep, Balb/c mice were immunized with peGn, pscCtrl-eGn, pscDEC-eGn or PBS combined with or without pGM-CSF as described above. After 2 immunizations (D42), significant levels of anti-eGn IgG in serum was measured in peGn-immunized mice alone or with pGM-CSF (p < 0.05 vs. PBS), and pGM-CSF did not improve the Ab response (Figure 3A). At D42, a significant Ab response was detected in mice immunized with pscCtrl-eGn and pscDEC-eGn with pGM-CSF (p < 0.05 vs. PBS), and the level of anti-eGn IgG Ab was lower in the pscDEC-eGn that in pscCtrl-eGn immunized group. After 3 immunizations (D60), lower Ab responses were observed in the serum of mice immunized with pscDEC-eGn than in mice immunized with pscCtrl-eGn in combination or not with pGM-CSF (p < 0.01 and p < 0.05, respectively). At both time points, the levels of anti-eGn IgG appear to be higher in the peGn-vaccinated group than in the pscCtrl-eGn-vaccinated group (no statistically significant differences). This could be due to the effect of the chimerization. The ELISA-positive sera were tested for their capacity to neutralize RVFV in a reduction plaque ass...
Source: Frontiers in Immunology - Category: Allergy & Immunology Source Type: research