Organ transplantation has been the most important therapeutic advance in the last third of the 20th century. Its development has revolutionized medicine, as demonstrated by the fact that a large number of researchers in this field have been awarded Nobel Prizes. In the beginning of this century, we are witnessing with great expectations the emergence of a new field of medicine related to the arrival of a new player on the scene: "stem cells" and their potential use in regenerative medicine. This volume aims to cover important aspects of the various facets of organ transplantation and regenerative medicine, with leading specialists in these fields setting out their vision. We try to rigorously explain current and novel scientific research in these fields-areas which arouse great interest from society in general, due to their potential use in modern medicine for the treatment of a great number of diseases.

In 1960 Sir Frank Macfarlane Burnet received the Noble Prize in Physiology and Medicine. He titled his Nobel Lecture "Immunological Recognition of Self" emphasizing the central argument of immunological tolerance in "How does the vertebrate organism recognize self from nonself in this the immunological sense-and how did the capacity evolve." The concept of self is linked to the concept of biological self identity. All organisms, from bacteria to higher animals, possess recognition systems to defend themselves from nonself. Even in the context of the limited number of metazoan phyla that have been studied in detail, we can now describe many of the alternative mechanism of immune recognition that have emerged at varying points in phylogeny. Two different arms-the innate and adaptive immune system-have emerged at different moments in evolution, and they are conceptually different. The ultimate goals of immune biology include reconstructing the molecular networks underlying immune processes.

Biological systems are an emerging discipline that may provide integrative tools by assembling the hierarchy of interactions among genes, proteins and molecular networks involved in sensory systems. The aim of this volume is to provide a picture, as complete as possible, of the current state of knowledge of sensory systems in nature. The presentation in this book lies at the intersection of evolutionary biology, cell and molecular biology, physiology and genetics. Sensing in Nature is written by a distinguished panel of specialists and is intended to be read by biologists, students, scientific investigators and the medical community.

It is now over ten years since we edited the first edition of HLA-B27 in the Development of Spondyloarthropathies (SpA). It is obvious that over this period an enormous amount of information concerning SpA and HLA-B27 has accumulated, and this has been reflected in the knowledge of molecular mechanism of the spondyloarthropathies. Discussion for such a book took initial form at the outstanding 4th Gent Symposium on SpA in October 2006, but was not formally commissioned by Landes Bioscience until early 2007. Molecular Mechanisms of Spondyloarthropathies aims to synthesize this growing knowledge and present all the current studies concerning the basic research of SpA. Over the last decade, enormous progress has been made in the understanding of the molecular and cellular processes that lead to disease pathology. Recognition of the pathways involved in the pathogenic mechanisms of disease and the potential to target specific immune effector functions have opened the door to a wide range of innovative treatment opportunities for the SpA. Thus, we believe that the understanding of the specific molecular mechanisms involved would help to design highly specific drugs in the future. The contributors are among the best in their field and reflect the state of the art of research and current opinion of rheumatologists and immunologists.