Organic dairy cows at Morris.

2016-17 Rapid Ag: A universal nanoparticle based mucosal delivery subunit vaccine for animal disease

July 1, 2016

Principle Leader

Srinand Sreevatsan

Department

Department of Veterinary Population Medicine

Funding Awarded

  • 2016 Fiscal Year: $111,000
  • 2017 Fiscal Year: $81,000

The Problem

Our long-term goal is to develop a versatile, safe, and orally or intranasally administered vaccine platform against infectious diseases of animals based on purified target antigens adsorbed to alginate nanoparticles. By utilizing nanoparticles, we take advantage proven safety in human, animal, and environmental systems, their remarkable resilience and stability, the ability to adsorb nearly any type of molecule, and the method of simple oral or intranasal delivery and resulting presentation of antigen directly to oral mucosal surfaces, mimicking the natural route of infection for most pathogens. Together, these benefits make feasible the vaccination for and control of pathogens in both domestic and wild animals. We will develop an effective mucosal vaccine against Johne’s disease (JD) as a proof-of-principle for universal animal and human applications.

Background

Infectious diseases inflict a massive burden globally. For example, in response to bovine tuberculosis farmers cull entire herds and implement expensive control measures, while other diseases such as Johne’s disease or avian influenza can present subtly, reducing yields of animal products (e.g., milk, meat, eggs) and impacting reproduction, lifespan, and quality-of-life. Wild animals often serve as reservoirs of infectious disease and transmit many pathogens to domestic animals or humans, with few options for control through modern vaccine technology. In many ways, strategies for disease control are purely reactionary, requiring disease to spread and be identified before an appropriate control is implemented.

JD is an insidious animal infection that continues to affect productivity in dairy cattle in the US and worldwide. Significant economic losses result due to premature culling, reduced milk production, and loss of body weight in animals sold for slaughter. Most recent estimates show that ~91% of US dairy herds are infected with Johne’s disease resulting in an annual cost of more than $200 million to the US dairy industry.

Objective

  1. Production of recombinant iron-regulated (ABC transporters [3776c], Esx III, mycobactin-MbtB, bacteroferritin-BfrA), intracellular survival proteins (MAP0403 - serine protease), and cell receptor proteins (heparin binding hemoadhesin and fibronectin binding protein) in M. smegmatis (strain MSM 4517 and associated vectors provided by Dr. William Jacobs) to generate the polyvalent formulation. We already have 3 (BfrA, MbtB, and MAP0403) of the 7 proteins cloned in this system. Our working hypothesis is that well defined, secretory and virulence antigens of MAP are sufficient to generate robust, protective immune responses against JD. Use of subunit vaccines also provides the option of differentiating vaccinated from infected animals (DIVA), a critical need in controlling infections without disrupting trade, such as Johne’s disease, bovine tuberculosis or avian influenza. The vector engineering proposed for this aim is routine for our laboratories (Sreevatsan, Murtaugh and Bannantine).

  2. Determine the protective efficacy of the polyvalent mucosal delivery vaccine formulation in a subcutaneous matrigel-based challenge model. Our working hypothesis is that MAP virulence proteins delivered, as an intranasal aerosol will provide maximum protective efficacy in neonates. We have extensive animal and vaccine delivery and immune response evaluation expertise to perform the work proposed under this aim. Dr. Hostetter (collaboration letter attached) is an expert in the matrigel-based immune evaluation and bacterial clearance system. He will help us in setting up of this specific part of the work. Dr. Stabel and Dr. Murtaugh are experts in immunology and have agreed to participate in this work to evaluate protective immune responses to MAP. We will seek help from UMN extension (Jim Paulson), MN BAH (Dr. Glaser) and industry partners (Pan Genome Systems and AccuDx) to help disseminate information and translate findings generated from the proposed vaccine trials. Dr. Godden is an epidemiologist and expert in study design and statistical analysis of clinical trial data. She will help navigate these aspects of the study.