This proposal, in response to RFA AI-07-003, is for the development of a future generation smallpox vaccine that can be safely administered to a diverse population. We have made great strides in the proof-of-principle selection of appropriate protein targets and the initial formulation of a protein-based smallpox vaccine. However, in order to bring the vaccine to the next level, optimization of the vaccine formulation and further improvements of the vaccine are required. To accomplish this, we bring together investigators with different areas of expertise and develop collaborations between academic researchers from different disciplines and with industry. Our hypothesis is that a protein-based smallpox vaccine can more safely elicit a protective response in a broad range of recipients than the current FDA approved live smallpox vaccine. While we have shown that this approach is feasible, there are a number of steps that are needed to bring this approach to the next level. The majority of our prior development of a protein-based smallpox vaccine has been with Vaccinia virus proteins, which based on their high homology to variola virus proteins, could confer cross protection against smallpox. There is theoretical and experimental evidence that variola proteins may ultimately be better candidates to generate protection against smallpox and therefore we will produce the variola virus homologs of A33, B5, and L1. Additionally, the formulation of the proteins with adjuvant needs to be optimized. An iterative and sequential process is now required to bring the vaccine to the next level. To accomplish this we will:
Aim 1. Produce the variola virus protein homologs of Vaccinia virus A33, B5, and L1 proteins (C-PERL) Aim 2. Optimize the protein/adjuvant vaccine formulation (U. Kansas) Aim 3. Evaluate, in a """"""""checkerboard"""""""" fashion, the ability of the optimized vaccine formulation to generate immune responses and protect from Vaccinia virus challenge in mice (U. Penn) Aim 4. Examine immune responses and protection from monkeypox challenge in a non-human primate model (Southern Research Institute)

National Institute of Health (NIH)
National Institute of Allergy and Infectious Diseases (NIAID)
Research Project--Cooperative Agreements (U01)
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Special Emphasis Panel (ZAI1-TP-M (J2))
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Challberg, Mark D
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University of Pennsylvania
Internal Medicine/Medicine
Schools of Medicine
United States
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Xiao, Yuhong; Zeng, Yuhong; Alexander, Edward et al. (2013) Adsorption of recombinant poxvirus L1-protein to aluminum hydroxide/CpG vaccine adjuvants enhances immune responses and protection of mice from vaccinia virus challenge. Vaccine 31:319-26
Xiao, Yuhong; Isaacs, Stuart N (2012) Enzyme-linked immunosorbent assay (ELISA) and blocking with bovine serum albumin (BSA)--not all BSAs are alike. J Immunol Methods 384:148-51
Isaacs, Stuart N (2012) Working safely with vaccinia virus: laboratory technique and review of published cases of accidental laboratory infections. Methods Mol Biol 890:1-22
Dehaven, Brian C; Gupta, Kushol; Isaacs, Stuart N (2011) The vaccinia virus A56 protein: a multifunctional transmembrane glycoprotein that anchors two secreted viral proteins. J Gen Virol 92:1971-80
Perino, Julien; Foo, Chwan Hong; Spehner, Daniele et al. (2011) Role of sulfatide in vaccinia virus infection. Biol Cell 103:319-31
Isaacs, Stuart N (2011) A stimulating way to improve T cell responses to poxvirus-vectored vaccines. J Clin Invest 121:19-21
Cohen, Matthew E; Xiao, Yuhong; Eisenberg, Roselyn J et al. (2011) Antibody against extracellular vaccinia virus (EV) protects mice through complement and Fc receptors. PLoS One 6:e20597
Buchman, George W; Cohen, Matthew E; Xiao, Yuhong et al. (2010) A protein-based smallpox vaccine protects non-human primates from a lethal monkeypox virus challenge. Vaccine 28:6627-36
Xiao, Yuhong; Isaacs, Stuart N (2010) Therapeutic Vaccines and Antibodies for Treatment of Orthopoxvirus Infections. Viruses 2:2381-2403