When discussing the drug, the bug, and the host in the past, emphasis was laid mainly upon the interaction between antibiotics and bacteria or the reaction of the host to the invading organism. Today, however, standardized immunologic parameters are available for evaluating cellular and humoral responses and an increasing number of publications deal with the host reaction to the antibiotics administered. Some re­ searchers and clinicians felt that the time had come to bring together investigators studying the influence of antibiotics on the host-parasite­ relationship. The first section of this book therefore covers the influence of chemotherapy on the host defense system. Here antibody production and cellular immunity, the influence of antibiotics on the function of phagocytic cells, and immunostimulation combined with antibiotics in the treatment of infection are presented. The second section deals with the influence of antibiotics on the produc­ tion of extracellular and cellular virulence factors by bacteria, the adherence of bacteria being of utmost importance here. In addition, phagocytosis and serum bactericidal activity are discussed. In Prof. Opferkuch and Prof. Hahn I found two colleagues keen and knowledgeable enough to organize the First International Meeting on the Influence of Antibiotics on the Host-Parasite-Relationship. These proceedings of the meeting constitute a survey of the latest develop­ ments in this field, and should be of interest to clinical and researchers. Bielefeld, September 1982 Hans-Udo Eickenberg Berlin Helmut Hahn Bochum Wolfgang Opferkuch Contents Introduction H. -U.

Section A: The Influence of Chemotherapy on the Host Defence System.- I. Antibody Production and Cellular Immunity.- Influence of Cephalosporins on Humoral Immune Response.- Immunosuppression by Rifamycins.- Suppression of Lymphocytes by Cephalosporins.- II. The Influence of Antibiotics on the Function of Phagocytic Cells.- Effect of Doxycycline and Puva Light on Human Polymorpho-nuclear Leukocyte Function.- The Effects of Antibacterial, Antiviral, and Antifungal Drugs on the Phagocytic, Microbicidal, and Chemotactic Functions of the Human Polymorphonuclear Leukocyte.- In Vivo Effect of Ampicillin and Cefaclor on Blood and Gingival Crevicular Neutrophil Myeloperoxidase Activity.- Enhanced In Vitro Phagocytosis of Different Pathogens by Human Monocytes in the Presence of Antibiotics.- The Influence of Antibiotics on the Phagocytosis-Associated Chemiluminescence of Guinea Pig Polymorphonuclear Neutro-phils.- Effect of Doxorubicin (Adriamycin) on Polymorphonuclear Leukocyte Function and the Protective Role of Alpha Toco-pherol (Vitamin E).- Chronic Granulomatous Disease: Effect of Sulfamethoxazole/ Trimethoprim on Neutrophil Microbicidal Function.- The Effect of Minocycline and Lysostaphin on the Intracellular Killing of Staphylococcus aureus by Polymorphonuclear Leukocytes.- The Effects of 13 Antimicrobial Agents on the Elimination Phase of Phagocytosis in Human Polymorphonuclear Leukocytes.- Effect of Cephalothin and Gentamicin on Phagocytosis of Klebsiella pneumoniae by Guinea Pig Alveolar Macrophages.- Capacity of Gentamicin-Treated Pseudomonas aeruginosa to Induce Granulocyte Locomotion.- Penetration of Antifungal Antimicrobics into Human Fibrin Clots.- III. Immunostimulation and Antibiotics in the Treatment of Infections.- Effect of Antibiotics and an Immunostimulanton the Ability of Immunosuppressed Mice to Defend Against Pseudomonal Infection.- The Combined Use of Antibiotics and Specific Antibodies Against Mouse Pseudomonas aeruginosa Infection in Vivo and the Phagocytosis of Peritoneal Exudate Cells In Vitro.- Section B: The Influence of Antibiotics on the Production of Extracellular and Cellular Virulence Factors by Bacteria.- I. Adherence of Bacteria.- Prevention of the Adhesion of Bacteria to Mucosal Surfaces: Influence of Antimicrobial Agents.- Effects of Low Concentrations of Antibiotics on Escherichia coli Adhesion.- II. Extracellular Factors.- Modification of the Expression of an Extracellular Virulence Factor (Cytotoxin) of Clostridium difficile Following Growth in the Presence of Clindamycin and Vancomycin.- III. Phagocytosis.- The Effect of Subinhibitory Antibiotic Concentrations on the Opsonization, Uptake, and Killing of Bacteria by Human Neutrophils.- The Susceptibility of Antibiotic-Pretreated Gram-Negative Bacteria to the Bactericidal Activity of Human Neutrophil Granule Extract.- Effect of Antibiotics on the Lysis of Staphylococci and Streptococci by Leukocyte Factors, on the Production of Cellular and Extracellular Factors by Streptococci, and on the Solubilization of Cell-Sensitizing Agents from Gram-negative Rods.- The Role of Autolytic Wall Systems in Wall Disintegration During the Phagocytosis of Staphylococci Treated with Antibiotics.- In Vitro and in Vivo Modulation of Escherichia coli Susceptibility to PMN Leukocyte Microbicidal Activity by a Pyrazole Cephalosporin Derivative.- IV. Serum Bactericidal Activity.- Effects of Antibiotics on the Bactericidal Activity of Normal Human Serum.- The Influence of Subinhibitory Concentrations of ?-Lactam Antibiotics on the Antibody-Independent Binding of the FirstComponent of Complement by Escherichia coli.