Immunobiology of the Macrophage presents an account of the state of knowledge of the immunobiology of the macrophage. The book's contributors—immunologists of diverse scientific and geographic backgrounds—have been encouraged to give personal accounts of developments in their special fields of interest as well as critical surveys of the backgrounds leading to these developments. The book begins with a study on the functions of macrophages in the initiation and regulation of antibody responses in vitro. This is followed by separate chapters on topics such as the role of macrophages in making antigen more immunogenic and less tolerogenic; functional distinctions between macrophages at different sites; and the role of the macrophage in antigen recognition by T lymphocytes. Subsequent chapters examine interactions between macrophages and lymphocytes in the production of interferon and other mediators of cellular immunity; macrophage cell lines and their uses in immunobiology; and cytotoxic macrophages in allograft rejection.

Monocytes represent one of the major types of white blood cells in man which prevent infection by ingesting and killing invading pathogens and by releasing factors which stimulate and regulate lymphocytes. Monocytes "purify" the blood, removing immune complexes, mediating inflammatory responses, and initiating tissue repair. Human Monocytes represents an up-to-date, definitive account of this important cell. It covers the cells biochemical, immunological, and inflammatory functionsand its role in many diseases, including asthma, atherosclerosis, rheumatoid arthritis, and AIDS.

The International Life Sciences Institute (ILSI) was estab lished in 1978 to stimulate and support scientific research and educational programs related to nutrition, toxicology, and food safety, and to encourage cooperation in these programs among scientists in universities, industry, and government agencies to assist in the resolution of health and safety issues. To supplement and enhance these efforts, ILSI has made a major commitment to supporting programs to harmon ize toxicologic testing, to advance a more uniform inter pretation of bioassay results worldwide, to promote a common understanding of lesion classifications, and to encourage wide discussion of these topics among scien tists. The Monographs on the Pathology of Laboratory Ani mals are designed to facilitate communication among those involved in the safety testing of foods, drugs, and chemicals. The complete set will cover all organ systems and is intended for use by pathologists, toxicologists, and others concerned with evaluating toxicity and carcinogen icity studies. The international nature of the project - as reflected in the composition of the editorial board and the diversity of the authors and editors - strengthens our ex pectations that understanding and cooperation will be im proved worldwide through the series. Alex Malaspina President International Life Sciences Institute Preface This book, on the hemopoietic system, is the eighth volume of a set prepared under the sponsorship of the International Life Sciences In stitute (ILSI).

The origin and function of normal monocytes and macrophages have been clearly defined by extensive investigations in human and in animal models. The central importance ofthis cell system for the biological defense mecha nisms is well established: phagocytosis, inactivation and destruction of organic and inorganic materials, an important role in the initiation ofhumo ral and cell mediated immunological responses, and the secretion of a varie ty of chemical mediator and effector substances are the most important fea tures of this ontogenetically ancient cell system. However, the data on this cellular system are rather recent, and this may explain why relatively little attention has been payed to the pathology of the monocyte-macrophage system (MMS) until now. In addition, this monograph should focus attention on the secondarypa thophysiological implications of the MMS in disorders not primarily origi nating from this system. Several techniques are available to identify even abnormal individuals of this cell system and, therefore, can be employed for the study of severely altered or neoplastic monocytic cells.

The mononuclear phagocyte system (MPS) comprises dendritic cells (DCs), monocytes and macrophages (MØs) that together play crucial roles in tissue immunity and homeostasis, but also contribute to a broad spectrum of pathologies. They are thus attractive therapeutic targets for immune therapy. However, the distinction between DCs, monocytes and MØ subpopulations has been a matter of controversy and the current nomenclature has been a confounding factor. DCs are remarkably heterogeneous and consist of multiple subsets traditionally defined by their expression of various surface markers. While markers are important to define various populations of the MPS, they do not specifically define the intrinsic nature of a cell population and do not always segregate a bona fide cell type of relative homogeneity. Markers are redundant, or simply define distinct activation states within one subset rather than independent subpopulations. One example are the steady-state CD11b+ DCs which are often not distinguished from monocytes, monocyte-derived cells, and macrophages due to their overlapping phenotype. Lastly, monocyte fate during inflammation results in cells bearing the phenotypic and functional features of both DCs and MØs significantly adding to the confusion. In fact, depending on the context of the study and the focus of the laboratory, a monocyte-derived cell will be either be called "monocyte-derived DCs" or "macrophages". Because the names we give to cells are often associated with a functional connotation, this is much more than simple semantics. The "name" we give to a population fundamentally changes the perception of its biology and can impact on research design and interpretation. Recent evidence in the ontogeny and transcriptional regulation of DCs and MØs, combined with the identification of DC- and MØ-specific markers has dramatically changed our understanding of their interrelationship in the steady state and inflammation. In steady state, DCs are constantly replaced by circulating blood precursors that arise from committed progenitors in the bone marrow. Similarly, some MØ populations are also constantly replaced by circulating blood monocytes. However, others tissue MØs are derived from embryonic precursors, are seeded before birth and maintain themselves in adults by self-renewal. In inflammation, such differentiation pathways are fundamentally changed and unique monocyte-derived inflammatory cells are generated. Current DC, monocyte and MØ nomenclature does not take into account these new developments and as a consequence is quite confusing. We believe that the field is in need of a fresh view on this topic as well as an upfront debate on DC and MØ nomenclature. Our aim is to bring expert junior and senior scientists to revisit this topic in light of these recent developments. This Research Topic will cover all aspects of DC, monocyte and MØ biology including development, transcriptional regulation, functional specializations, in lymphoid and non-lymphoid tissues, and in both human and mouse models. Given the central position of DCs, monocytes and MØs in tissue homeostasis, immunity and disease, this topic should be of interest to a large spectrum of the biomedical community.

Dieses Fachbuch erläutert die molekularen Grundlagen von Entzündungen, spannt den Bogen zu Infektionskrankheiten und den Zusammenhang zwischen Entzündungen und chronischen Erkrankungen, behandelt abschließend den Heilungsprozess und zeigt Therapiemöglichkeiten.