Twenty-five years have passed since J. MILLER'S basic work on the central role of the thymus for the generation of immunological reactivi ty. During this time, the abundance of fascinating literature on the immunological and functional aspects of this organ has been in contrast to the paucity of reports on its role in pathology. The causal or formal pathogenesis even of many of the well-documented pathological fea tures is so far unexplained or at least uncertain. In spite of some concep tual progress related to the work of CASTLEMAN, LEVINE, and ROSAI, we regrettably have to say that in pathology the thymus remains almost as inconspicuous as 25 years ago. Only the new techniques developed in recent years have made it possible to look as closely into the complicated structural organization of the thymus as it appears to be necessary to observe and document abnormalities. Major steps have been taken with the advent of mono clonal antibody immune histochemistry and with detailed ultrastructur al studies in embryology. At this point, pathologists and researchers with a special interest in the thymus were asked to give overviews of their respective fields of interest in light of recent findings in immunology and basic insights into the structural-functional interrelationship of the human thymus. The results of this initiative have been brought together in this volume.

The Janeway's Immunobiology CD-ROM, Immunobiology Interactive, is included with each book, and can be purchased separately. It contains animations and videos with voiceover narration, as well as the figures from the text for presentation purposes.

T cells play a vital role mediating adaptive immunity, a specific acquired resistance to an infectious agent produced by the introduction of an antigen. There are a variety of T cell types with different functions. They are called T cells, because they are derived from the thymus gland. This volume discusses how T cells are regulated through the operation of signaling mechanisms. Topics covered include positive and negative selection, early events in T cell receptor engagement, and various T cell subsets.

The thymus is a gland that over the last two centuries has generated great awareness not only from the anatomical perspective but also for the physiological and pat- logical roles it plays in many disease processes. Prior to the early studies on its th anatomy and physiology in the 18 century, the thymus was believed to perform - usual and curious functions such as purification of the nervous system, providing a protective cushion for the vasculature of the superior mediastinum, fetal nouri- ment, or more spiritual roles such as being the seat of the soul, among others. D- th ing the 19 century important anatomical/physiological studies took place focusing on the role of the thymus in pathological conditions. However, it was not until the th middle of the 19 century that a more comprehensive analysis of the role of the thymic gland and its role in pathogenesis began to emerge. Currently, while the knowledge gained on the diverse aspects of the thymic gland has furthered our understanding of its role in a gamut of processes, more knowledge is still being sought, and by no means is a full understanding of the gland’s physi- ogy and pathology complete. Different aspects, including its purported endocrine function, its association with other autoimmune diseases like multiple sclerosis, rheumatoid arthritis, and lupus erythematosus, among others, are under evaluation and research.

The Human Thymus presents the immunological aspect of the thymus. It discusses the lymphopoietic and immunological functions of the human thymus. It addresses the physiological function of thymus that regulates neuromuscular transmission by the secretion of thymin. Some of the topics covered in the book are the origin of thymic lymphocytes; development of Hassall's corpuscles; humoral immune responses; neonatal thymectomy and wasting disease; mode of action of thymin at the neuromyal synapse; experimental autoimmune thymitis; and neuromuscular block associated with experimental autoimmune thymitis. The diseases induced with Freund's complete adjuvant are covered. The spontaneously occurring autoimmune diseases are discussed. The text describes the size of the human thymus. A study of the experimental effect of hormones on thymic size is presented. A chapter is devoted to the thymic hypoplasia and immunological deficiencies. Another section focuses on the histopathology of thymus in myasthenia gravis. The book can provide useful information to scientists, doctors, students, and researchers.

WHO Classification of Tumours of the Lung, Pleura, Thymus and Heart is the seventh volume in the Fourth Edition of the WHO series on histological and genetic typing of human tumors. This authoritative, concise reference book provides an international standard for oncologists and pathologists and will serve as an indispensable guide for use in the design of studies monitoring response to therapy and clinical outcome.