The Evolution of the Immune System: Conservation and Diversification is the first book of its kind that prompts a new perspective when describing and considering the evolution of the immune system. Its unique approach summarizes, updates, and provides new insights on the different immune receptors, soluble factors, and immune cell effectors. Helps the reader gain a modern idea of the evolution of the immune systems in pluricellular organisms Provides a complete overview of the most studied and hot topics in comparative and evolutionary immunology Reflects the organisation of the immune system (cell-based, humoral [innate], humoral [adaptive]) without introducing further and misleading levels of organization Brings concepts and ideas on the evolution of the immune system to a wide readership

The comparative approach to immunology can be traced to the era of Pasteur and Metchnikov in which observations regarding foreign recognition in invertebrates was a factor in the develop ment of the principal concepts that created the foundation of what now is the broad field of immunology. With each major experimental and conceptual breakthrough, the classical, albeit essential, question has been asked "are the immune systems of phylogenetically primitive vertebrates and invertebrates similar to that of mammals?" Somewhat surprisingly for the jawed verte brates, the general answer has been a qualified form of "yes", whereas for agnathans and invertebrate phyla it has been "no" so far. The apparent abruptness in the appearance of the immune system of vertebrates is linked to the introduction of the somatic generation of the diversity of its antigen specific receptors. Therefore the questions regarding the origin and evolution of the specific immune system revolve around this phenomenon. With respect to the origin of the system (aside from the or igin of the rearranging machinery itself, the study of which is still in its infancy) one can ask questions about the cellular and mo lecular contexts in which the mechanism was introduced.

Immunology is a nodal subject that links many areas of biology. It permeates the biosciences, and also plays crucial roles in diagnosis and therapy in areas of clinical medicine ranging from the control of infectious and autoimmune diseases to tumour therapy. Monoclonal antibodies and small molecule modulators of immunity are major factors in the pharmaceutical industry and now constitute a multi billion dollar business. Students in these diverse areas are frequently daunted by the complexity of immunology and the astonishing array of unusual mechanisms that go to make it up. Starting from Dobzhansky’s famous slogan, “Nothing in biology makes sense except in the light of evolution”, this book will serve to illuminate how evolutionary forces shaped immunity and thus provide an explanation for how many of its counter intuitive oddities arose. By doing so it will provide a conceptual framework on which students may organise the rapidly growing flood of immunological knowledge.

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.

Publisher Description

There is a long-standing evolutionary battle between viruses and their hosts that continues to be waged. The evidence of this conflict can be found on both sides, with the human immune system being responsive to new viral challenges and viruses having developed often sophisticated countermeasures. The “arms race” between viruses and hosts can be thought as an example of the “Red Queen” race, an evolutionary hypothesis inspired from the dialogue of Alice with the Red Queen in Lewis Carroll’s “Through the Looking-Glass”. At the same time, viruses have a minimal genomic content as they have evolved to hitchhike biological machinery of their hosts (or other co-infecting viruses). The minimalistic viral genome could be thought as the result of a “Black Queen” evolution, a theory inspired from the card game Heart, where the winner is the one with the fewest points at the end. The effects of this arms race are evident in the evolution of the human immune system. This system is capable of responding to diverse viral challenges, utilizing both the ancient innate immune system and the more recently evolved adaptive immune system of jawed vertebrates. It is now well-known that the two systems are linked, with innate immunity hypothesized to have provided raw material for the emergence of the adaptive immune response. The adaptive immune response comprises several protein families (including B and T cell receptors, MHC and KIR proteins, for example) that are encoded by complex and variable genomic regions. This complexity enables for responsive genetic changes to occur in immune cells, such as the ability of genomic hypervariable regions in B cells to recombine in order to produce more specific antibodies. Indeed, the human immune system is thought to be continually evolving via various mechanisms such as changes in the genes encoding immune receptors and the regulatory sequences that control their expression. For example, there is some evidence that exogenous viral infections can alter the expression of endogenous retroviruses, some of which contribute to the immune response. Viral countermeasures can include encoding decoy receptors for the signalling molecules of the immune response, altering the gene expression of adaptive immune cells during chronic infection or using host enzymes to facilitate viral immune escape. As the articles herein show, the immune system continues to be challenged by viral infections and these challenges continue to shape how the immune system combats pathogens, thus viruses and human immunity are continuously part of “Red and Black Queen” evolutionary dynamics. We had the pleasure of working with Jonas Blomberg as a reviewer during the course of the Research Topic and his untimely passing was a great loss. Prof. Blomberg made significant contributions, including to the nomenclature of endogenous retroviruses (ERVs), the evolution and characterization of specific human ERV (HERV) and the contribution of ERVs to diseases such as cancer. It is with great respect for his contributions to the ERV field that we dedicate this eBook to his memory.