9809876 Rollins-Smith The studies proposed here will examine the role of specific hormones and growth factors on development of the immune system using an amphibian (frog) model system. Why study frogs? Frogs belong to an ancient class of vertebrates (animals with backbones) valued by naturalists around the world. They have a complex neuroendocrine system that enables them to flourish in a variety of aquatic environments. They also have a complex immune system that enables them to resist infection by disease organisms. Amphibians undergo metamorphosis which involves the destruction and reorganization of the whole body including the immune system. All higher vertebrates, including humans, are distantly related to frogs, and understanding the interactions of hormones and growth factors with the developing immune system in frogs may provide insight into these complex interactions in other species. Another compelling reason to try to understand the neuroendocrine and immune systems of the frog is that naturalists have recently observed the decline in a number of frog species worldwide. The causes for this alarming trend are not well-understood, but manmade disturbances to the ecosystem are suspected. These disturbances may result in the impaired function of the frog's immune system with increased susceptibility to disease. These studies also have the potential to assist in the training of developmental biologists and immunologists.
