"Ecology is the study of the distribution and abundance of organisms and their interactions with their environment, including parasites and pathogens. Immunology is the study of the physiological functioning of the immune system in states of health and disease. The former discipline implicitly acknowledges the importance of the latter but treats it as a black box. Likewise, the latter discipline implicitly acknowledges the importance of variation between individuals, but relies on a logistic foundation that necessarily removes individual variation from its empirical approach and so avoids the complex interactions which determine an organism's life history in its natural environment."
H. Schulenburg, J. Kurtz, Y. Moret, M. and T. Siva-Jothy. Introduction. Ecological immunology.
Philosophical Transactions of the Royal Society B: Biological Sciences 364, 3 (2009).
My research is driven largely by the question of how the ecology of an organism affects the development and maintenance of its immune system. Conversely, I am also interested in how the immune system can affect behavior and ultimately fitness. Animals, such as
spotted hyenas (Crocuta crocuta) and Tasmanian devils (Sarcophilus harrisii), that consume other animals are likely exposed to pathogens from their food. Scavenging animals take this one step further and are also exposed to a wide range of potential pathogens that can be found in decomposing carcasses. Modern humans have managed to avoid this problem by eating fresh or frozen food and also by cooking their food. Scavenging carnivores must be able to either tolerate or eliminate the pathogens they obtain from their food without the aid of a freezer or cooking their food. However, the prevalence of allergies and autoimmune diseases is rapidly increasing in human populations, whereas autoimmune diseases are rarely documented in wild animals.
My Ph.D. focused on understanding the immune system of spotted hyenas, and how ecology affects immune function in hyenas. Spotted hyenas are highly social and frequently engage in aggressive interactions; therefore, if a pathogen enters a hyena population and is capable of replicating, it is likely to spread throughout the population. Populations of other large carnivores such as
African lions (Panthera leo) and wild dogs (Lycaon pictus) have undergone large fluctuations in population size due to outbreaks of canine distemper virus (CDV) and rabies, but hyena populations remained stable during the same periods. Despite documented seroprevalences of 37%, 47%, and 87% for antibodies to rabies, CDV, and anthrax, respectively, hyena populations under intense study exhibited little or no mortality from disease.
Following the completion of Ph.D. I moved to Australia and began working as a postdoctoral research associate in the Experimental Therapeutics Laboratory under the direction of John Hayball and Kerrilyn Diener at UniSA. Our work in the ETL focused on the production of viral vectors to treat and/or prevent peanut allergy, skin cancer, prostate cancer, and chikungunya virus.
In 2014 John Hayball (UniSA), Greg Woods (UTas), and I launched the Tasmanian devil immunotherapy project to develop a treatment for the Tasmanian devil facial tumor. Our project was initially funded by a Dr Eric Guiler Tasmanian Devil Research Grant from the Save the Tasmanian Devil and a Sansom Institute grant to develop immunotherapeutics to treat Tasmanian devils that are infected with the devil facial tumour disease (DFTD). The approach we are taking is based on similar immunotherapeutics that have achieved unprecedented success in treating human cancer (Science Magazine Breakthrough of the Year 2013). We are also initiating a comparative analysis between the DFTD and the canine transmissible venereal tumor (CTVT), the only other known naturally transmissible tumor. The goal of this comparative analysis is to develop immunotherapeutics to treat cancer in pets.
Prior to enrolling as a Ph.D. student at MSU, I worked in the immunology lab of Lieping Chen. Dr. Chen's laboratory specializes in functional characterization of interactions among cell surface molecules. Much of the research is focused on costimulatory signaling in lymphocytes and how these signals can modulate immune function in relation to cancer and autoimmune diseases. My primary job functions were to produce new hybridomas that produce antibodies against novel cell surface molecules and characterize the antibodies using ELISA, flow cytometry (FACS), Western blots and T cell proliferation assays. As lab manager I was also responsible for day to day operations of the lab and helping with IACUC and IRB protocols.