Human T-cell leukemia virus type 1 (HTLV-1) and HTLV-2 are among the first human retroviruses discovered in the early 1980s. The International Retrovirology Association is an organized effort by scientists and clinicians to form interdisciplinary groups to study these retroviruses and their related diseases. The Association promotes excellent science, patient education, and training of young scientists to promote bench-to-bedside research. The International Conference on Human Retrovirology: HTLV and Related Viruses, sponsored by the Association, supports clinicians and researchers in the exchange of research findings and stimulation of new research directions. Since its inception in 1988, these conferences have provided a highly interactive forum for the global community of HTLV scientists. This is of particular importance as HTLV research enters its third decade and a new generation of scientists takes over this important work. Many of the scientists attending these meetings are from developing countries where HTLV is endemic, consistent with the history of international collaborations that have characterized HTLV research. The International Conference on Human Retrovirology provides a unique opportunity for researchers of all disciplines interested in HTLV infections to meet their peers and to address the questions facing clinicians and scientists who study HTLV and related retroviruses.
Albert Einstein said, "the problems that exist in the world today cannot be solved by the level of thinking that created them." This belief was part of the foundation of the International Retrovirology Association when it was established in May, 1994. At that time, informal discussions among established HTLV scientists, representing such diverse disciplines as epidemiology, virology, immunology, and clinical medicine, came together at the 6th International HTLV Conference in Absecon, New Jersey. This organized effort, from its beginning, fostered the efforts of scientists and clinicians to form interdisciplinary groups to study HTLV and its related diseases in a cooperative and innovative manner. With the growth of the conference over the next decade, the founders recognized that a professional association was needed to promote shared goals of member scientists and to provide governance and continuity to the international conference and other activities.
History of The International Conference on Human Retroviruses
The Association has evolved since these humble beginnings to now promote research and education in the field of human retrovirology at the international level, including scientific conferences, interdisciplinary research collaborations, and educational exchanges to the study of HTLV and related viruses. The Association has chosen to focus on HTLV and other related human and nonhuman primate retroviruses, in part, because numerous other organizations and conferences already exist to study human immunodeficiency virus (HIV). The Association strives to promote excellent science in the field of HTLV and related viruses and to facilitate the communication of scientific results. The Association fosters the education and training of young scientists who will contribute to and expand the field. The Association promotes bench-to-bedside research that translates findings from the laboratory into clinical trials that benefit HTLV-infected patients. In addition, the Association promotes awareness of and education about HTLV and related viruses to non-specialist physicians and the broader public.
HTLVs, Related Retroviruses and Disease Associations
HTLV-1 and the closely related HTLV-2 were among the first human retroviruses discovered in the early 1980s . Both viruses are highly related to simian T- lymphotropic viruses (STLV-1 and STLV-2, respectively), presumably from cross-species transmissions of the simian viruses to humans. The discovery pf HTLV-3 and -4, indicate that cross species transmission may still occur in situations where humans are exposed to nonhuman primate blood . Thus, in this context, the HTLVs are actually members of a broader group of primate T-lymphotropic viruses found worldwide. HTLV-1 is classified as a member of the deltaretrovirus genera and infects approximately 20 million people worldwide . HTLV-1 is the etological agent of adult T-cell leukemia/lymphoma (ATL/L), an aggressive malignancy of CD4+ T-lymphocytes in 1 to 5% of infected individuals and comes in a variety of clinical presentations, but is refractory to most forms of therapy . The virus is also associated with a progressive neurologic disease termed HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) that affects approximately the same number of infected subjects, but rarely concurrent with ATL/L . HTLV-2 does not appear to cause lymphoma or other hematological malignancy, but has been associated with neurologic disease in a small number of infected subjects, and may increase the susceptibility to bacterial infections . HTLV-1 is endemic in Central Africa, the Caribbean, and South America likely due to the slave trade, and southwestern Japan, while HTLV-2 is endemic among indigenous tribes of South, Central, and North America. Both viruses may be transmitted by blood transfusion and the sharing of contaminated injection apparatus, by sexual intercourse, and from mother to child through breastfeeding. Injection drug use, with secondary sexual transmission, has resulted in the spread of both HTLV-1 and HTLV-2 in the United States and Europe. The potential contamination of HTLVs in the blood supply makes them an important public health issue in areas with high prevalence and has led many countries, including the United States and Japan, to screen normal blood donors for these viruses [7-9]. In addition, the HTLVs serve as models for the epidemiology and pathogenesis of other human retroviral infections such as HIV.
An International Association to Promote Scientific Exchange and Discovery
The International Retrovirology Association accomplishes its goals through a variety of activities. Principal among these is the sponsorship of its biennial general scientific conferences held at rotating international venues, generally in areas with endemic HTLV infection. This unique meeting brings together basic scientists, epidemiologists, and clinical researchers in a free-form exchange of data to discuss approaches to prevent HTLV infection or develop new therapies against HTLV-mediated diseases. The Association also sponsors smaller symposia and regional meetings directed at specific topics such as disease pathogenesis, treatment of HTLV diseases, and regional epidemiology of this group of retroviruses. The group also honors the contributions of leading scientists through endowed awards to leaders in the HTLV research field and promotes partnerships with professional journals to promote the publication of HTLV research and conference proceedings. By funding travel scholarships for the biennial conference to young investigators, the Association encourages the next generation of retrovirologists and physician-scientists. The International Conference on Human Retrovirology HTLV and Related Viruses is a biennial conference that fulfills the continuing scientific need for the exchange of research findings and stimulation of new research directions. Basic scientists who study the molecular biology of HTLVs continue to grapple with the problem of how these viruses cause cancer. They have discovered important clues in this process by studying the viral gene product called Tax, and other factors that support virus replication. The conference also brings together those scientists that seek to understand the pathogenesis of HAM/TSP, which occurs presumably via aberrant immunologic response to the viral infection. The immune-mediated nature of HAM/TSP in infected subjects with particular HLA genotypes suggest important host factors in understanding this disease and provides a comparative model for other neuro-immunologic diseases such as multiple sclerosis. Clinicians and other scientists employing traditional and molecular epidemiologic tools have been reasonably successful at defining important public health issues related to HTLV infections. These discoveries have led to improved preventative measures to block mother to child transmission, better confirmatory test strategies for blood donor screening, and the prevention of HTLV-2 infection among injection drug users . Despite these advances, ongoing clinical and basic research is needed to develop potential HTLV-1 vaccines and for improved treatments for ATL/L and HAM/TSP. The biennial HTLV conference serves as an important stimulus for all of these research areas.
The International Retrovirology Association, through its many varied approaches, aims to encourage research in HTLV infections and disease, foster collaborations between research groups, provide a platform for critical analysis of new data, and contribute to the dissemination of knowledge about these infections. While the biannual scientific meeting has been the cornerstone of the Association's activities, there is increasing recognition of the need for more rapid progress in improving the management of HTLV-associated malignant and inflammatory diseases. The Association is ideally positioned to facilitate this process through its membership.
- Laboratory Medicine and Epidemiology/Biostatistics, University of California at San Francisco and Blood Systems Research Institute, San Francisco, California, USA
- Viral Immunology Section, National Institute of Immunology and Neurological Diseases, National Institutes of Health, Bethesda, Maryland, USA
- Animal Models & Retroviral Vaccines Section, National Cancer Institute, Bethesda, Maryland, USA
- Gastrointestinal and Urogenital Medicine and Communicable Diseases, Imperial College, Norfolk Place, London, United Kingdom
- Department of Pathology and Medical Sciences, University of the West Indies, Kingston, Jamaica, West Indies
- Center for Retrovirus Research, Department of Veterinary Biosciences, and Comprehensive Cancer Center, The Ohio State University, Columbus, Ohio, USA
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