BOVINE IMMUNE RESPONSES TO TICK-BORNE PATHOGEN TRANSMISSION

Bovine Anaplasmosis is a tick-borne disease that results in estimated losses of over 300 million USD per year in the US. Bovine Anaplasmosis is caused by the obligate intracellular pathogen Anaplasma marginale, which infects red blood cells, resulting in anemia, fever, weight loss, decreased milk production, spontaneous abortions, and, in naïve herds, can cause up to 30% mortality. Treatment cost can be over 400 USD per animal in the US, imposing a financial burden to cattle producers. Recent studies indicate that current treatments may not be effective and no commercial vaccine is available in the US. The development of an effective vaccine is needed, but it is hindered by several factors: 1) the ability of pathogen to escape cattle's immune responses, 2) the capacity of tick saliva to hamper the cow's immune response and 3) the ability of the bacteria to enhance the detrimental effects of tick's saliva on the immune system of the animal.The aim of theseprojects is to understand how A. marginale affects bovine skin immune responses and alters the immune gene expression at the bite site.The long-term goal of our project is to define the factors that are important for the transmission and establishment of bovine. We will identify the host immune components that lead to protection. With this knowledge, it is likely that applied scientist will be able to develop vaccines or treatments to this disease.The shor-term goalsof this project areto: 1) determine the changes in immune response at the tick feeding site during pathogen transmissionand 2) characterize the changes in salivary secretions during the transmission ofA. marginale.Through the development of a more complete understanding of the tick-pathogen-host interactions at the time of initial infection, we will identify additional antigens and mechanisms that could be leveraged for the development of a vaccine that protects against A. marginale infection in cattle.