Distinguished Professor Emeritus
Center for Comparative Medicine
SOM: Pathology and Laboratory Medicine
University of California, Davis
Research Interests: Comparative Pathology, Retroviruses
Although officially retired, Dr. Gardner remains an active and vital member of the CCM. Dr. Gardner's major research interest for many years has been in the natural history of retroviruses in animals and man. As part of the Virus Cancer Program (VCP) from 1968-1981 he and his colleagues at USC School of Medicine in Los Angeles discovered and characterized oncogenic retroviruses of wild mice and domestic cats and carried out extensive studies on the epidemiology and virology of human cancer. This led to the understanding of a new biology of retroviruses in wild mice that proved a more accurate model than inbred mice for predicting the natural history of similar retroviruses (i.e. HTLV) discovered a decade later in humans. Study of naturally occurring retroviruses in cats led to an appreciation of the horizontal transmission of feline leukemia virus among domestic cats and contributed to the eventual development of a vaccine that now largely prevents this feline disease. This research also led to discovery and characterization of several novel oncogenes in feline sarcomas which are now potential targets for novel cancer therapy in humans. Endogenous inherited infectious but nonpathogenic retroviruses were discovered in cats, mice and rats. Most importantly, in respect to public health, endogenous retroviruses, despite representing ~8% of the human genome, were found to not contribute significantly to human cancer, thus ruling out a major hypothesis of the VCP. However, the VCP established the “blue print”, technology and teamwork that led to the current molecular/genomic era and facilitated the discovery of the immunosuppressive retroviruses that cause AIDS in humans and animals.
Since moving to UC Davis in 1981, Dr. Gardner has taken part in the discovery and description of simian AIDS caused by Type D retrovirus and also by simian immunodeficiency virus (SIV, which is closely related to human immunodeficiency virus, HIV-1). Research on the Simian AIDS model was indispensable in leading to the development of successful antiviral drugs that have changed AIDS from an inevitable fatal disease to a long lived chronic infection. He and his colleagues have studied the origin, natural history, pathology and pathogenesis of these retroviruses and have carried out a number of experimental vaccine trials. A potentially efficacious human AIDS vaccine based on cytomegalovirus research in the Simian AIDS model is now in phase II human trials. His present interest is directed at better understanding of the pathogenesis of AIDS and attempts to develop more efficacious and safe vaccines against AIDS using the SIV macaque model.