Protection of mice against the highly pathogenic VVIHD-J by DNA and fowlpox recombinant vaccines, administered by electroporation and intranasal routes, correlates with serum neutralizing activity

Abstract

Please cite this article as: Bissa, M., Quaglino, E., Zanotto, C., Illiano, E., Rolih, V., Pacchioni, S., Cavallo, F., De Giuli Morghen, C., Radaelli, A., Protection of mice against the highly pathogenic VV IHD-J by DNA and fowlpox recombinant vaccines, administered by electroporation and intranasal routes, correlates with serum neutralizing activity, Antiviral Research (2016Research ( ), doi: 10.1016Research ( / j.antiviral.2016 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. and fowlpox (FP) recombinants that expressed the VV L1R, A27L, A33R, and B5R genes were generated (4DNAmix, 4FPmix, respectively) and tested in mice using novel administration routes. Mice were primed with 4DNAmix by electroporation, and boosted with 4FPmix applied intranasally. The lethal VV IHD-J strain was then administered by intranasal challenge. All of the mice receiving 4DNAmix followed by 4FPmix, and 20% of the mice immunized only with 4FPmix, were protected. The induction of specific humoral and cellular immune responses directly correlated with this protection. In particular, higher anti-A27antibodies and IFNγ-producing T lymphocytes were measured in the blood and spleen of the protected mice, as compared to controls. VV IHD-J neutralizing antibodies in sera from the protected mice suggest that the prime/ boost vaccination regimen with 4DNAmix plus 4FPmix may be an effective and safe mode to induce protection against smallpox and poxvirus zoonotic infections. The electroporation/ intranasal administration routes contributed to effective immune responses and mouse survival.

Construction of a recombinant avipoxvirus expressing the env gene of Zika virus as a novel putative preventive vaccine

“…It is known that, although many epitopes of ZIKV are very similar to those of other flaviviruses, higher concentrations of antibodies are needed for virus neutralization compared to other flaviviruses [29]. We have also previously demonstrated that the specific neutralizing response may be hidden by the aspecific activity, detected in naïve mice or in control mice immunized with irrelevant immunogens [44]. However, our previous study showed that vaccinated mice can be protected and survive also when a very low neutralization titer is used, with an increase in specific vs aspecific antibodies.…”

“…After deletion of the A27L gene from pFP A27L recombination plasmid [43,44] and subcloning of the cPrME fragment, the resulting pFPcPrME18 clone was sequenced to exclude any possible mistakes due to the PCR amplification. A non-synonymous mutation at nucleotide 759, where the cytosine nucleotide had replaced the thymine giving origin to an alanine instead of a valine, was corrected by site-specific mutagenesis [45,46].…”

“…The neutralizing activities of the mice sera were determined by measuring the extent of in-vitro inhibition of virus infectivity at T0 (pre-immune serum) and T6 (pre-challenge serum). The assays were performed as previously described [44], by pre-incubation of an equal volume of ZIKV with heat-inactivated mouse serum, used at different dilutions (1:50 to 1:1600, in DMEM without serum) in 48-well plates, for 1 h at 37 °C. Briefly, the viral titer was adjusted to provide approximately 80 PFU ZIKV in the assays.…”

Vector Order Determines Protection against Pathogenic Simian Immunodeficiency Virus Infection in a Triple-Component Vaccine by Balancing CD4 + and CD8 + T-Cell Responses

“…Vaccination experiments performed in mice indicated that FWPV recruited a significantly smaller portion of the unfavorable CD11b Ϫ CD103 ϩ but elevated levels of favorable CD11b ϩ CD103 Ϫ dendritic cells to lung tissue than MVA or vaccinia virus (44). FWPV-based vaccines, administered in combination with a DNA prime, have been reported to induce neutralizing antibodies (45,46) and strong CD4 ϩ and CD8 ϩ T-cell responses (23-25, 30, 47, 48). Therefore, they have been considered for vaccination against cancer in humans (47,49,50) and against a variety of viral infections in different species (31,32,45,46).…”

“…FWPV-based vaccines, administered in combination with a DNA prime, have been reported to induce neutralizing antibodies (45,46) and strong CD4 ϩ and CD8 ϩ T-cell responses (23-25, 30, 47, 48). Therefore, they have been considered for vaccination against cancer in humans (47,49,50) and against a variety of viral infections in different species (31,32,45,46). Both vaccination regimes used in our study resulted in significantly reduced peak viremia and reduced set point viral load after infection compared to controls.…”