Infectious diseases in animal production are increasingly untreatable due to the worldwide rise of antibiotic resistance. Developing new non-antibiotic treatments is a priority in both human and veterinary medicine. For pigs, antibiotic resistance in swine dysentery (SD) is particularly troubling. SD is caused by a highly contagious spirochete Brachyspira hyodysenteriae, which colonizes the colon of young pigs to cause colitis and severe hemorrhagic diarrhea. Without treatment, mortality can reach 30% in naturally infected herds. SD is a concerning animal welfare problem for the pork industry, causing decreased production, increased treatment costs and culling of infected animals. Antibiotics largely eliminated B. hyodysenteriae in the 1990s, but antimicrobial resistance has recently caused its resurgence. Current treatments still rely on large amounts of antibiotics that exacerbate resistance, so new therapies stand to greatly benefit the pork industry. Developing new treatments requires an understanding of host immune responses, which remain largely unknown in SD.
 
This project aims to understand how the porcine gut immune system responds to infection during SD and use this knowledge to evaluate novel therapeutic targets. Our aims are to describe the kinetics of the mucin barrier and neutrophil recruitment (white blood cells that kill bacteria) over the course of B. hyodysenteriae infection. We are partnered with Dr. Hancock and his research team at the University of British Colombia, who have developed synthetic peptides derived from natural cathelicidins to test whether Innate Defense Regulators (IDRs) alleviate SD.