Avian Leukosis

The intention of the series Developments in Veterinary Virology is to provide monographs dealing with the major animal viral diseases. Each volume will include the latest achievements in fundamental research and practical applications and should be readable for people from various disciplines and different backgrounds. The multi-author approach provides the best opportunity to keep each chapter at the highest level and makes the composition of the volumes manageable to the editors. This monograph on Avian Leukosis presents comprehensive reviews on the recent history of avian retrovirus research, on epizootiological, virological, pathological aspects, on tumor induction, the immune response to avian retro­ viruses, virus-cell interactions and on techniques for diagnosis. The volume deals mainly with exogenous avian leukosis virus (ALV) infections, but one chapter is entirely devoted to endogenous avian leukemia virus. Molecular biology aspects are confined to various oncogenes and to lymphoma induction since retroviruses, including those specific for avian species, have recently been described in detail in the Cold Spring Harbor Laboratory series "Molecular Biology of Tumor Viruses". Two chapters are devoted to the practical application of insights obtained from avian leukosis research: influences of AL V infection on production performance and eradication procedures.

Contenu

1.A historical review of avian retrovirus research.- 1. The origins of avian retrovirus research 1908-1945.- 2. Avian retrovirus research during the period 1945-1960.- 3. Contemporary research with avian retroviruses 1960-1984.- 4. Concluding remarks.- 2.Structure and virus-associated oncogenes of avian sarcoma and leukemia viruses.- 1. Introduction.- 2. Defective leukemia viruses.- 3. Avian sarcoma viruses.- 4. Concluding remarks.- 3.Epizootiology of avian leukosis virus infections.- 1. Introduction.- 2. Virus classification.- 3. Incidence and prevalence.- 4. Modes of natural transmission.- 5. Infection patterns within flocks.- 6. Viral factors influencing infection and disease.- 7. Host genetic factors influencing infection and disease.- 8. Other host factors influencing infection and disease.- 9. Environmental factors influencing infection and disease.- 4.Molecular basis of oncogenesis by non-acute avian retroviruses.- 1. Introduction.- 2. Structure and replication of non-acute retroviruses.- 3. The structure of the long terminal repeat (LTR).- 4. Possible schemes for host oncogene activation by non-acute retroviruses.- 5. B-lymphoma induction by ALV: c-myc activation.- 6. B-lymphoma induction by REV: c-myc activation.- 7. Erythroblastosis induction by ALV: c-erbB activation.- 8. RPV-induced neoplasms.- 9. MAV-induced neoplasms.- 10. Concluding remarks.- 5.Endogenous avian leukemia viruses.- 1. Introduction.- 2. Evidence that normal chickens harbor avian retroviral genes.- 3. The endogenous ALV genome.- 4. Expression of ev genes.- 5. Transcriptional control elements within the long terminal repeat.- 6. Chromosomal distribution of ev genes.- 7. Significance of ev genes among avian species.- 8. Genetic diversity among avian retroviruses.- 9. Biological influences of endogenous proviruses.- 6.Immunology of avian leukosis virus infections.- 1. Introduction.- 2. Neoplastic transformation of lymphoid cells.- 3. Immune response to ALV infection.- 4. Immunosuppression.- 7.Avian sarcomas: immune responsiveness and pathology.- 1. Introduction.- 2. Cellular transformation by avian sarcoma viruses.- 3. Viral-associated antigens.- 4. ASV-induced pathogenesis and immunosuppression.- 5. Development of anti-tumor immunity in tumor-bearing hosts.- 6. The immunogenicity of retroviral envelope glycoprotein.- 7. Characteristics of tumor cell growth in vivo and in vitro.- 8.Virus-cell interactions of avian sarcoma and defective leukemia viruses.- 1. Introduction.- 2. Avian sarcoma viruses.- 3. Pathogenic effects of avian sarcoma viruses in vivo.- 4. Transforming effects of avian sarcoma viruses in vitro.- 5. Defective avian leukemia viruses.- 6. Conclusions and future trends.- 9.The pathogenesis and pathology of neoplasms caused by avian leukosis viruses.- 1. Introduction.- 2. Virus classification.- 3. Factors affecting the pathogenic response.- 4. Classification of leukemias and leukoses.- 5. Other tumors and tumorous conditions.- 6. Non-neoplastic conditions.- 7. Transplantability and development of cell lines.- 8. Lymphoid leukosis.- 9. Erythroblastosis.- 10. Myeloblastosis.- 11. Nephroblastomatosis.- 12. Osteopetrosis.- 13. Concluding remarks.- 10.Differential diagnosis of lymphoid leukosis.- 1. Introduction.- 2. Clinical signs.- 3. Etiology.- 4. Pathogenesis.- 5. Gross pathology.- 6. Microscopic pathology.- 7. Serological and immunological techniques.- 11.Laboratory diagnostic procedures for detecting avian leukosis virus infections.- 1. Introduction.- 2. Collection and handling of specimens.- 3. In vivo assay of RSV and ALV.- 4. In vitro assay of RSV and ALV.- 5. Production of virus stocks and antiserum.- 6. Tests based on interaction between ALV and RSV.- 7. Tests for ALV based on detection of group-specific antigens.- 8. Detection and distribution of viral antigens in host tissues.- 9. Detection of antibody against subgroup- and group-specific antigens.- 10. Concluding remarks.- 12.Influences of avian leukosis virus infection on production and mortality and the role of genetic selection in the control of lymphoid leukosis.- 1. Introduction.- 2. Frequency of ALV infection.- 3. Effects of ALV infection on production and mortality.- 4. Prospects for the future.- 13.Approaches to control avian lymphoid leukosis.- 1. Introduction.- 2. Detection of congenital ALV transmission.- 3. Prevention of horizontal virus exposure.- 4. LL control by elimination of ALV shedding hens.- 5. Manipulation of the immune response.- 6. Genetic resistance.- 7. Concluding remarks.