IX The International Seminar on the Immunological System as a Target for Toxic Damage was held at The Commission of the European Communities (CEC) in Luxembourg on 6-9 November 1984. It was organized by the CEC and the International Programme on Chemical Safety of UNEP/ILO/WHO with the support of the u. S. Environmental Protection Agency and the National Institute of Environmental Health Sciences - USA and with the participation of the International Society of Immunophar- macology. These bodies are actively concerned with the scientific and applied aspects of immunotoxicology. The Seminar consisted of thirty-four invited papers and three major panel discussions covering current and future test strategies for the screening of immunotoxic substances, hypersensitivity and the health implications of immunotoxico- logical problems. It was attended by more than 200 scien- tists from 27 countries representing all the Member states of the European Economic Community and the six Regions of the World Health Organization. These scientists represented many different disciplines and interests. The Seminar's principal objectives were: a review of recent advances in knowledge concerning the structure, function and dysfunction of the immunological system; - a review of the effects of xenobiotics on the immune system in animals and humans; an examination of the human health implications of immunotoxicity; discussion and critical analysis of the procedures for the assessment of immunological damage, a discussion of needs for the further development of laboratory and epidemiological methods and their validation, and a consideration of current test strategies.

Session I.- A Toxicologist's View of Immunotoxicology.- The Cells of the Immune System. An Up-date on their Interactions and Signals.- Relationships Between the Immune System and Cancer.- The Immune System and Infections.- Mechanisms of Autoimmunity.- Session II.- Primary Immunodeficiencies.- The Neoplastic Consequences of Immunodepression.- Immunological Abnormalities in the Acquired Immunodeficiency Syndrome.- Monitoring the Human Immune System.- Immunorestoration in Secondary Immunodeficiency.- Session III.- The Role of Histopathology in Assessment of Immunotoxicology.- Experience with Validation of Methodology for Immunotoxicity Assessment in Rodents.- An In Vitro Model for Studying Cellular and Molecular Mechanisms of Thymic Atrophy Induced by Chlorinated Aromatic Compounds.- The Gut-Associated Lymphoid Tissue as a Model of a Specialized Immune Subsystem.- Immunodepressive Drugs as Prototype Immunotoxicants.- The Toxicology of Biological Response Modifiers.- MTP-PE, a Synthetic Lipophilic Muramyltripeptide: Biological and Toxicological Properties.- Session IV.- Altered Immune Function and Host Resistance Following Exposure to Common Airborne Pollutants.- Immunotoxicity of Organotin Compounds. A Cell Biological Approach to Dialkyltin Induced Thymus Atrophy.- Immunosuppressive Effects of Benzidine in BCF Mice.- Mechanisms of Metal-Induced Immunotoxicity.- Some Aspects of Immune Alterations Induced by Chloro-Dibenzo-p-dioxins and Chloro-Dibenzofurans.- Immunotoxicological Effects of Asbestos.- Immunotoxicity of Dimethylnitrosamine.- Session V.- Clinical Immunology Studies in Individuals Exposed to Environmental Chemicals.- Immunological Effects of Diethylstilbestrol in the Human.- Immune System Disorders Associated with Adulterated Cooking Oil.- Vulnerability to Toxic or Therapeutic Immunomodulation - As Two Complementary Aspects of Age and Nutrition Dependent Immunodeficiency.- Session VI.- Basic Mechanisms in Hypersensitivity. An Update.- Mechanisms of Pseudo-allergy.- Prospective Modeling for Delayed Contact Hypersensitivity.- Allergic Drug Reactions.- Contact Hypersensitivity to Environmental Chemicals.- Lung Reactions to Environmental Chemicals.