Performing Department
Pathobiology
Non Technical Summary
Influenza A viruses (IAV) cause siginifianct ecomonic loss in livestock industry. The zoonotic nature of the virus also pose a significant pandemic threat to human population. Pigs have long been considered a mixing vessel for generation of novel influenza viruses. The recent emergence and outbreaks of highly pathogenic avian influenza (HPAI) H5N1 virus in cattle have increased concern of IAV panzootic/pandemic in animals and human population. An universal vaccine that can induce strong, broadly protective immunity against genetically diversified viral strains is urgently needed. Current commercial influenza vaccine platforms and manufacturing procedures present a challenge for us to respond to an influenza outbreak in a timely manner. Nucleic acid-based (mRNA) vaccine platforms allow for flexible, nimble, large-scale production of vaccines, which can meet the rapid manufacturing requirements during an influenza outbreak. In this proposed study, we will test an mRNA vaccine "cocktail", which contains a mixture of mRNAs encoding a chimeric HA (H1) globular head, with two types of conserved HA stalk domain covering 16 IAV subtypes, and the H5 antigen from HPAI H5N1. These mRNAs will be delivered by a novel class of peptide-based cationic nanoparticles (PNP) featuring resistance to oxidation and thermal stability. This candidate mRNA-PNP vaccine will be initially characterized in cell culture model and the immunogenicity of vaccine will be assessed in animal models, including pigs and calves.
Animal Health Component
40%
Research Effort Categories
Basic
20%
Applied
40%
Developmental
40%
Goals / Objectives
The overall goal of this proposed project is to develop a broadly protective influenza mRNA vaccine with novel nanoparticle delivery platform. Specific objectives are: 1). To construct and characterize influenza mRNA-PNP nanoparticles; 2). To evaluate PNP nanoparticle delivery method and determine cytotoxicity of mRNA-PNP nanoparticles in cell culture; 3). To assess broadly protective immunity induced by influenza mRNA-PNP vaccine in animal models.
Project Methods
The purpose of this project is to develop a broadly protective influenza mRNA vaccine using novel nanoparticle delivery approach. Initially, mRNA encoding antigens of HAs will be prepared. Each of the mRNA will be encapsulated into the PNP (BAPC or APC) to generate mRNA-PNP nanoparticle vaccine. The optimal ratio of mRNAs complexed with BAPC or APC will be determined by zeta potential measurement, and the physical properties of the nanoparticles will be further characterized. Subsequently, the efficiency of cellular uptake of influenza mRNA-PNP nanoparticle constructs will be tested on cell culture. The expression of influenza virus antigens and cytotoxicity in influenza mRNA-nanoparticle construct-treated cells will be determined. Subsequently, in vivo mRNA vaccine delivery methods will be evaluated using a nursery pig model. The specific immunity induced by influenza mRNA-PNP nanoparticle vaccine, including anti-H5 response, will also be tested in young calves. To assess the protective immunity induced by the mRNA-PNP vaccine, immunized pigs will be further challenged with virulent swine influenza A viruses. The degree of protection will be determined, and the breadth of immunity will be further assessed by measuring serum antibody responses against a panel of genetically diversified influenza virus isolates.