A Novel Vaccine Using Nanoparticle Platform to Present Immunogenic M2e against Avian Influenza Infection

Abstract

Using peptide nanoparticle technology, we have designed two novel vaccine constructs representing M2e in monomeric (Mono-M2e) and tetrameric (Tetra-M2e) forms. Groups of specific pathogen free (SPF) chickens were immunized intramuscularly with Mono-M2e or Tetra-M2e with and without an adjuvant. Two weeks after the second boost, chickens were challenged with 107.2 EID50 of H5N2 low pathogenicity avian influenza (LPAI) virus. M2e-specific antibody responses to each of the vaccine constructs were tested by ELISA. Vaccinated chickens exhibited increased M2e-specific IgG responses for each of the constructs as compared to a non-vaccinated group. However, the vaccine construct Tetra-M2e elicited a significantly higher antibody response when it was used with an adjuvant. On the other hand, virus neutralization assays indicated that immune protection is not by way of neutralizing antibodies. The level of protection was evaluated using quantitative real time PCR at 4, 6, and 8 days post-challenge with H5N2 LPAI by measuring virus shedding from trachea and cloaca. The Tetra-M2e with adjuvant offered statistically significant (P < 0.05) protection against subtype H5N2 LPAI by reduction of the AI virus shedding. The results suggest that the self-assembling polypeptide nanoparticle shows promise as a potential platform for a development of a vaccine against AI.

Expression of peptide nanoparticles containing a porcine reproductive and respiratory syndrome (PRRS) virus epitope in plants

“…We designed two constructs, M-GP5 which yields icosahedral nanoparticles whereas T-GP5 yields octahedral nanoparticles. According to Babapoor et al (2011), M-GP5 seems to contain the highest density of the epitope. We will be testing them separately in future immunological challenges in mice and pigs.…”

“…The peptide nanoparticles M-GP5 and T-GP5 sequences were synthesized by GenScript from the nanoparticles sequences previously reported by Babapoor et al (2011). These nanoparticles will display the antigen of interest in a repetitive manner in high density in both monomeric (M-GP5) or tetrameric form (T-GP5) which are different conformations of the structure (Babapoor et al, 2011).…”

“…These nanoparticles will display the antigen of interest in a repetitive manner in high density in both monomeric (M-GP5) or tetrameric form (T-GP5) which are different conformations of the structure (Babapoor et al, 2011). The conserved epitope B (SHLQLIYNL) of GP5 PRRSv protein (Ostrowski et al, 2002) was genetically fused to the nanoparticle sequence (Table 1).…”

“…The nanoparticles are formed by pentameric and trimeric motifs derived respectively from coiled coil domains of a monomer taken from the cartilage oligomeric matrix protein and a de novo designed oligomer (Babapoor et al, 2011;Raman et al, 2006). These pentameric and trimeric coiled coils oligomers, use the threefold and fivefold symmetry of an icosahedron to yield a self-assembling nanoparticle (Raman et al, 2006).…”

“…Self-assembly into a predicted regular icosahedral nanoparticle of about 16 nm of diameter and 473 KDa in size occurs when the coiled-coil domains of different monomers associate to form the icosahedral nanoparticle. A nanoparticle with this type of architecture can be used as a vaccine by extending the ends of the monomer with an epitope sequence (Babapoor et al, 2011). Nanoparticles of this type have only been expressed in bacterial systems and employed to express epitopes of Plasmodium berghei (Kaba et al, 2009), avian influenza (Babapoor et al, 2011) and severe acute respiratory syndrome virus (Pimentel et al, 2009).…”