The field of cytokine research is expanding at a rapid pace. Contributions from the major leading groups in the world on the structure and biological properties of cytokine and cytokine receptors, as well as integrated reviews on cytokines in various physiological and pathological conditions were presented in three issues of International Reviews of Immunology. This collection of articles provided a unique source of information. However, important discoveries are emerging very rapidly and some of the reviews written in 1997 are already outdated. In this book, the editors assemble reviews that have been updated by their authors to include all the recent publications and unpublished data from the authors' laboratories. This volume should serve as an excellent reference source for all those concerned by the multiple faces of cytokines in basic research and in the clinic.