Enhancement of Immune Response to Porcine Reproductive and Respiratory Syndrome (PRRS) Vaccine by Interferon Alpha


Porcine reproductive and respiratory syndrome (PRRS) is a major problem for hog farmers worldwide. PRRS is caused by a virus which leads to reproductive failure in sows and respiratory problems in piglets and growing pigs. The PRRS virus spreads rapidly, leading to large economic losses for farmers and overall lower health for pigs. Currently, PRRS is controlled by inoculating pigs with modified live virus which stimulates the immune system of pigs against the PRRS virus. However, this therapy does not prevent PRRS virus infection and is limited by individual pigs ability to create a strong immune response against the vaccine. The current technology is a composition and method for use that enhances the immune response to PRRS vaccine for the purpose of improving the vaccines efficacy against the PRRS virus.

One of the challenges with PRRS is that the PRRS virus is resistant to pigs natural immune response. The PRRS virus is able to hide from the natural defense system by being resistant to signals that alert the body of the viruses presence. Interferon-a is one such alert signal that PRRS virus fails to up-regulate. The current technology uses plasmids (or related technologies) to increase interferon-a production during administration of modified live virus vaccine. By doing so, interferon-a interacts with T cells to create virus specific interferon-? secreting cells. The result is a robust immune system response to the vaccine which should strengthen the immune systems ability to fight infection of PRRS virus.


  • Can be used as a supplement to PRRS vaccines for swine
  • Has broad application for hog farmers and veterinary clinics


  • Strengthened immune system: In vivo application of interferon-a and modified live virus to pigs resulted in over 3x as many virus specific interferon-? secreting cells as modified live virus application alone 
  • Reduction in abortion/still births: Amount of PRRS virus specific interferon-? secreting cells is positively correlated with reduction of abortion/still births in sows