Opening Remarks -- A. Theoretical Part -- Destruction of Complement-Target Cell Complexes by Mononuclear Leukocytes -- Anticomplementary Activity of Guinea Pig Serum Euglobulin: Its Relation to C 1 and to TAMe Esterase -- Experimental Inhibition of Complement -- Molecular and Stereochemical Properties Required of Antigens for the Elicitation of Allergic Reactions -- Mammalian Erythrocyte Receptors: Their Nature and Their Significance in Immunopathology -- Studies on the Structure and Formation of Antibodies -- Structure and Formation of Antibodies -- The Significance of the Carrier for the Induction of Antibodies -- The Effect of Cytostatic Agents on Nucleic Acid and Protein Synthesis and on Immunological and Non-Immunological Inflammation -- Studies on the Cytotoxicity of Lymphocytes -- Contact Sensitivity and Immunological Tolerance as Competitors in Sensitization to Simple Chemical Compounds -- Results of some Investigations on Lymphocyte Transformation in Vitro -- In-Vitro Stimulation of Lymphoid Cells by Antilymphocytic Globulins -- The In Vitro Transformation of Lymphocytes of Premature and Mature Infants -- Cell-Bound Antibodies to Streptococcal Cell-Wall Preparations -- Delayed Hypersensitivity and Tumor Specific Immunity -- Histological Changes in NZB/NZW Mice -- B. Clinical Part -- Clinical and Serological Aspects of the Aetiologic Differentiation of Auto-Immune Haemolytic Anaemias -- The Pathogenesis of Hemolytic Diseases of the ABO-System of the Newborn -- Immune Phenomena in Pernicious Anaemia -- Immune Reactions in Chronic Liver Diseases -- Cellular Immune Reactions in Experimental Hepatitis -- Quantitative Serum Immunoglobulin Determinations in Active Chronic Hepatitis and Idiopathic Cirrhosis -- The Possible Role of Lipid-Containing RNA Viruses for the Ethiology of Autoimmune Diseases -- Humoral Antibodies in Older Humans -- Experimental Glomerulonephritis in Unresponsive Rabbits after Termination of Immunologic Tolerance -- The Long Acting Thyroid Stimulator (LATS) in Thyrotoxicosis -- Immunological Investigations in Myasthenia Gravis and other Skeletal Muscle Disorders -- Comparative Studies of the Immunopathology of Inflammatory Cardiovascular Diseases -- Possible Bithermic Pathomechanism in Cryoglobulinemic Vasculitis -- Amyloid Involvement and Monoclonal Immunoglobulins -- Research in Drug Allergy: A Search for Impurities ? -- Immunogenicity of Semisynthetic Penicillins -- Author Index