A remarkable spectrum of novel immunoreceptors sharing related immunoglobulin-like domains and signaling potential has been identified in recent years. These receptors have attracted widespread interest because they resemble the TCR, BCR, and FcR complexes in their ability to serve as activating or inhibitory receptors on the cells that bear them. Moreover, they are well positioned to affect both innate and adaptive immunity. The full range of ligands for these new receptor families is still not known, and understanding of their physiological roles is far from complete. This volume is the first attempt to summarize and highlight all known aspects of immunoglobulin-like receptors, providing a topical overview of the roles and characteristic features of the immunoglobulin-like receptors and related molecules in the immune system. Researchers in immunology, molecular biology, cell biology, clinical medicine, and pharmacology will find this book invaluable.

and how the known vertebrate homologues of these genes are expressed normally in differentiation and proliferation pathways as well as abnormal ly in well-defined lymphomagenic and other oncogenic pathways. What emerged from this meeting are a better understanding of the evolution of these gene systems themselves and an elucidation of simpler systems open to more rapid genetic and molecular genetic analysis to reveal the normal functions of these genes and their gene products. Thus we sought new answers to several old questions concerning differenti ation, proliferation, and neoplastic transformation. We gathered together in an unusual format - that of the unique Dahlem Workshops - not just to reiterate data which has recently emerged but to think about how these findings might lead to new approaches for the understanding and therapy of the leukemias and lymphomas. We deliberately chose experts from several different disciplines, ranging from the clinicians who diag nose, describe, and treat these maladies, to the molecular geneticists trying to reduce the analysis of the problem to its simplest variables in the simplest systems possible."

A remarkable spectrum of novel immunoreceptors sharing related immunoglobulin-like domains and signaling potential has been identified in recent years. These receptors have attracted widespread interest because they resemble the TCR, BCR, and FcR complexes in their ability to serve as activating or inhibitory receptors on the cells that bear them. Moreover, they are well positioned to affect both innate and adaptive immunity. The full range of ligands for these new receptor families is still not known, and understanding of their physiological roles is far from complete. This volume is the first attempt to summarize and highlight all known aspects of immunoglobulin-like receptors, providing a topical overview of the roles and characteristic features of the immunoglobulin-like receptors and related molecules in the immune system. Researchers in immunology, molecular biology, cell biology, clinical medicine, and pharmacology will find this book invaluable.

The subject of immune deficiency has become of special importance for two reasons. First, conditions with well defined defects in the immune system could be analyzed as "experiments of nature" in terms of finding out the accurate biological relevance of the defective link in the immune system. Secondly, the recognition of immune deficiency states has become important in order to provide the patients with the treatment necessary to remedy these defects. With regard to immune deficiency states in patients, these have been instrumental as "experiments of nature" in the revelation by Drs. Good and Cooper and their associates of the two-component structure of the immune system, a discovery which can be consi dered as a major breakthrough in the history of immunopathology. Today's research allows us to go far beyond this basic two component structure with the assessment of disorders affecting either cell to cell interactions or regarding subsets of lymphocyte populations. Furthermore, the association of immune deficiency with distinct enzymatic defects of purine metabolism is opening the door to the molecular level of immune deficiency. Dr. Cooper and Dr. Lawton have succeeded in obtaining the collaboration of the leaders in the field of immune deficiency. In view of the importance of their contributions in scientific and clinical terms, we decided to prepare a book version of the two issues of Seminars in Immunopathology devoted to this subject."