Enhancing interferon-gamma in foals

Scientific Importance: Describe the research plan in lay terms. This page should be shorter and less detailed than the previous page. This abstract will be used to explain your research to the directors of the Foundation, the press, the general public, and potential donors. Newborn foals are faced with a number of challenges after birth including exposure to infectious and opportunistic pathogens. While maternal antibodies provide some protection until the foal's own immune system is able to deal with these challenges, young foals exhibit unique susceptibilties to respiratory infections particularly those caused by the bacterium Rhodococcus equi. This bacterium causes a severe pneumonia in young foals. As the foals age they become resistant to this disease, though the reason for this age-dependent susceptibility reamins unclear. We have determined that foals are deficient in the production of interferon-gamma, an important cytokine that plays a key role in resistance to this bacterium. Here we propose to idetermine the nature of this defect and to dentify a way to increase interferon-gamma expression in foals in order to increase their resistance to R. equi and other pathogens. We will test both commercially available immune stimulants for their ability to increase interferon-gamma in foals. Importance to the Equine Industry: Describe the importance of the proposed project to the equine industry in lay terms. Rhodococcus equi is considered the most common cause of severe pneumonia in young foals and remains one of the most important challenges to the equine industry. Current control methods for R. equi are expensive, inconvenient, and not always effective. There is no currently available effective vaccine against R. equi pneumonia of foals. The relative immaturity of the foal's immune system and the fact that initial exposure to the bacterium likely occurs in the first weeks of life dminishes the prospects for developing an effective vaccine. Alternatvie strategies, including non-specifically enhancing the resistance of foals to this infection, are needed. We have determined that part of the susceptibility of foals to this infection likely involves their inability to produce a key cytokine, interferon-gamma, needed for resistance to this infection. By increasing their production of this key protein, we hope to increase their resistance to this disease.