All pathology work will be performed in the laboratory of Dr. Andrew Miller at the Cornell University College of Veterinary Medicine. This includes histologic preparation of tissues, immunohistochemistry, and in situ hybridization. The immunohistochemistry protocols have already been standardized and include CD68, Mac387, CD3, CD20, CD4, and CD8 to immunophenotype the inflammation. Additional markers of simian immunodeficiency virus will also be used based on protocols that have already been standardized. Dr. Miller’s lab contains the appropriate reagents to handle these procedures and is supported by two cores: immunohistochemistry and basic histology. If novel immunohistochemical assays are to be developed, Dr. Miller’s lab will work in concert with Lynn Dong to develop new assays in the immunohistochemistry core. The histology laboratory will provide the cutting and slide preparation services.