Robert J Kearns

Professor
Full-Time Faculty
College of Arts and Sciences: Biology

Profile

Dr. Robert Kearns is a professor of biology and is a past director of Premedical Programs.

Research Interests

Research interests currently focus on the effects of dietary nutrients on immune function. Man and other animals are normally able to protect themselves from environmental factors such as infectious disease agents, allergens, and toxins. Protection from these agents is controlled either by natural or acquired resistance mechanisms. Natural or innate resistance involves those non-specific factors provided at birth, and include numerous biochemical, physical and anatomical barriers. In addition, phagocytic cells including macrophages and neutrophils are involved in the engulfment and destruction of many of these harmful agents. Should innate resistance fail, acquired resistance provides protection for the host. Acquired resistance involves cells of the immune system, and consists of humoral (antibody) and cellular immunity. To survive, the host depends on an elaborate network of communication between cells of the immune system. Ironically, two variables affecting immune function are the aging process and nutritional factors. Aging has been demonstrated to influence both humoral and cellular immune function, as well as cytokine production. Consequently, the aging immune system may contribute to the increased incident of infectious disease and cancer. Malnourished animals are immunocompromised and exhibit an increased incidence of both infectious diseases and cancer. Dietary lipids, vitamin E and ß-carotene have each been reported to modulate the immune system either through regulating cytokines, or eicosanoids (prostaglandins and leukotrienes) which influence several immune parameters, including T and B cell function, as well as cytokine profiles. Carotenoids, i.e., ß-carotene, exhibit biological activities as antioxidants, affect cell growth regulation and modulate gene expression and immune function. Likewise, a deficiency in vitamin E results in reduced lymphocyte and leukocyte killing, as we4ll as interfering with antibody production, and suppression of cellular immunity. Research currently ongoing in my lab is evaluating the effects of dietary fatty acids, vitamin E and carotenoids on T cell function and cytokine production in young and old animals.

Selected Publications

R. J. Kearns, M.G. Hayek, J.J. Turek, M. Meydani, J.R. Burr, R.J. Greene, C.A. Marshall, S.M. Adams, R.C. Borgert, and G. A. Reinhart (1999). "Effect of age, breed and dietary omega -6 (n-6):omega-3 (n-3) fatty acid ratio on immune function, eicosanoid production, and lipid peroxidation in young and aged dogs." Vet. Immunol. and Immunopath. In press.

Oglesbee, M.J., Diehl, K., Crawford, E., Kearns, R., and Krakowka, S. (1999) "Whole body hyperthermia: Effects upon canine immune function and hemostatic function." Vet. Immunol. and Immunopath. In press.

Robert J. Kearns, S.S. Ringler, G.S. Krakowka, R. Tallman, J. Sites, and M. Oglesbee (1999). "The effects of extracorporeal whole body hyperthermia on the functional and phenotypic features of canine peripheral blood mononuclear cells." Clinical Experimental Immunology. 116:188-192.

Robert J. Kearns, Michael G. Hayek and Gregory D. Sunvold. "Microbial changes in aged dogs. Recent Advances in Canine and Feline nutrition," Vol. II: 1998 Iams International Nutrition Symposium Proceedings. 337-351, 1998.

Michael G. Hayek, Robert J. Kearns, John J. Turek, Mohsen Meydani, John R. Burr, Susan Alexander, and Gregory A. Reinhart. "Influence of dietary omega 6:3 fatty acid ratio on the immune response of young and old fox terriers and labrador retrievers." Proceedings of the 16th Annual Veterinary Medical Forum. American College of Veterinary Internal Medicine. 16-19, 1998.