9317267 Felten Prior NSF support and an extraordinary arrangement between the Canadian Department of Fisheries and Oceans, native Canadian hunters, the Naval Command, Control and Ocean Surveillance Center R,D,T, and E Division (NRaD) have permitted these investigators to obtain fresh tissue specimens from beluga whales, Delphinapterus leucas, taken during sanctioned hunts. These tissues were collected at a relatively short postmortem interval with excellent preservation of antigens for immunocytochemical localization of neurotransmitters and neuropeptides in these organs. These tissues have been used for the first detailed study of the general morphology of Beluga lymphoid organs, providing the foundation for investigating neural-immune interactions in these mammals. The next goals of this research are to continue to obtain fresh tissue specimens of the immune and nervous systems from beluga whales and to use cells dissociated from fresh thymus, spleen and lymph nodes to carry out in vitro immunological assays to test the hypothesis that norepinephrine and neuropeptides found in these nerves in beluga lymphoid organs can influence functional characteristics and responses of cells of the immune system. Monoclonal antibodies against cetacean lymphocyte antigens will be generated to identify cellular compartments in lymphoid organs according to specific subsets of cells, and compare overall organization with that of other mammals. The monoclonal antibodies will be used with flow cytometry to monitor percentages of lymphocyte subsets and to separate populations of cells for functional assays. A number of in vitro functional assays will be developed and used to study the effects of noradrenergic agonists, antagonists, or neuropeptides on lymphocytes and leukocytes from beluga peripheral blood, thymus, lymph nodes, and spleen. %%% The long term goal of this research is to understand the structure and function of the immune system in a marine mammal, the beluga whale, and to determine how the nervous system and immune system may interact in regulating the normal health and well being of these unique animals. Prior NSF support and special arrangements with the Canadian government, native Canadian hunters, and the US Navy have enabled these investigators to obtain tissue samples from whales killed by native Canadian hunters in sanctioned hunts. Using these samples, the structure of the major lymphoid organs was described and it was demonstrated that the sympathetic nervous system has nerve branches which contact major lymphocyte- containing areas of these organs. This suggests that the nervous system may be involved in regulating immune function in these animals as has been suggested for other mammals. The next goals of this research are to define more precisely the cell types involved in the whale immune response, and to develop the technical tools needed to study how neurotransmitters may affect their function. The results of these studies will provide the groundwork of basic knowledge that should make it possible, in the longer term, to develop rational approaches to promote optimum health of marine mammals in captivity and for conservation of these unique species. ***
