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The fruit fly Drosophila melanogaster is an established tool to study mechanisms of innate immunity. Drosophila flies and larvae launch elegant humoral and cellular innate immune responses against bacteria, viruses, fungi and parasites. The humoral immune response is based on microbial recognition primarily by peptidoglycan recognition proteins leading to the production of antimicrobial peptides (AMPs). In the past few decades, Drosophilists have dissected how flies react to systemic bacterial and fungal infections at the molecular level and shown how these mechanisms are conserved from human to man. Fly humoral immune response is mainly mediated by two evolutionarily conserved NF-κB signaling pathways, the Toll and the Immune deficiency (Imd) pathways. The discovery of the Toll receptor as a key regulator of immune response, first in cultured Drosophila cells and then in Drosophila in vivo, formed the basis of the Toll-Like Receptor (TLR) research in humans and mammals. More recently, this field has broadened considerably, including e.g. the antimicrobial responses taking place in the gut. Another interesting aspect related to innate immunity is the antiviral immune mechanisms found in Drosophila. Best understood are the mechanisms based on RNAi, primarily against RNA virus infections. More recently, the evolutionarily conserved molecule STING has been shown to integrate responses against both viruses and bacteria.

A link between inflammation and cancer was initially made by Rudolf Virchow back in the 19th century. Nowadays many cancers are considered dependent on inflammatory responses to microbial and damaged-self stimuli and both arms of immunity, innate and adaptive, are playing a role in promoting cancer. Moreover, besides environmental factors, opportunistic pathogens contribute to inflammation and cancer. Nevertheless, microbial influence on chronic disease is sometimes difficult to discern, especially in the context of polymicrobial communities, such as those found in the digestive tract. In this light, model organisms provide important insights into immune and growth signals that promote cancer, and suggest therapies that will selectively target potentially harmful microbes or modulate host responses. A number of review and opinion articles in this series address novel aspects and paradigms of the interactions between the microbiota and the host in relation to inflammation and cancer.

Recent molecular studies have revealed an overwhelming role of hemolymph proteins and functional peptides in invertebrate physiology. This is mainly due to the large assortment of biomolecular factors each with a different structure and function. In addit

Well-written, readable, and superbly illustrated, Cellular and Molecular Immunology, 10th Edition, continues the tradition of excellence established through multiple editions of this bestselling text. Offering an unparalleled introduction to this complex field, it retains a practical, clinical focus while updating and revising all content to ensure clarity and comprehension, bringing readers fully up to date with new and emerging information in this challenging area. It's an ideal resource for medical, graduate, and undergraduate students, as well as a trusted reference for physicians and scientists. - Highlights the implications of immunologic science for the management of human disease, emphasizing clinical relevance throughout. - Employs a highly accessible writing style that makes difficult concepts easier to understand, and provides clear implications of immunologic science to the management of human disease and clinical practice. - Features updates from cover to cover, including new information on intracellular sensors of innate immunity, therapeutic use of monoclonal antibodies, regulation of migration events during T cell-B cell interactions, regulatory and transcriptional events in germinal center formation, immunology of infectious diseases including coronaviruses, human immunodeficiency disorders, and immunology of HIV. - Provides a highly visual, full-color description of the key immunologic and molecular processes with a fully updated, comprehensive, and consistent art program, including many new and extensively revised illustrations. - Helps readers grasp the details of experimental observations that form the basis for the science of immunology at the molecular, cellular, and whole-organism levels and draw the appropriate conclusions. - Includes summary boxes that assist with rapid review and mastery of key material. - Evolve Instructor site with an image and test bank is available to instructors through their Elsevier sales rep or via request at https://evolve.elsevier.com.

The interplay between host and pathogen is a complex co-evolutionary battle of surveillance and evasion. The pathogen continuously develops mechanisms to subvert the immune response in order to establish infection while the immune system responds with novel mechanisms of detection. Because the majority of Lyme disease pathology is due to an over-exuberant immune response, much research in Borrelia burgdorferi pathogenesis has been devoted to understanding the mammalian host response to the bacterium. Immunological studies continue to be an active area of research employing emerging techniques, such as intra-vital imaging. These studies have furthered our understanding of inflammatory processes during long-term infection and provided some surprising insights, such as the continued presence of bacterial products after clearance. The field of Lyme disease has long debated the etiology of long-term inflammation and recent studies in the murine host have shed light on relevant cell types and inflammatory mediators that participate in the pathology of Lyme arthritis. Live imaging and bioluminescent studies have allowed for a novel view of the bacterial life cycle, including the tick mid-gut, tick-to-mammal transmission and dissemination throughout a mouse. A number of tick and bacterial proteins have been shown to participate in the completion of the enzootic cycle. Novel mechanisms of gene regulation are continuously being identified. However, B. burgdorferi lacks many traditional virulence factors, such as toxins or specialized secretion systems. Many genes in the B. burgdorferi genome have no known homolog in other bacteria. Therefore, studies focusing on host-pathogen interactions have therefore been limited by an incomplete understanding of the repertoire of bacterial virulence factors. Questions such as how the pathogen causes disease, colonizes the tick and evades host immune-surveillance have been difficult to address. Genetic studies involving single gene deletions have identified a number of important bacterial proteins, but a large-scale genomics approach to identify virulence factors has not been attempted until recently. The generation of a site-directed mutagenesis library is an important step towards a detailed analysis of the B. burgdorferi genome and pathogenome. Using this library, high-throughput genomic studies, utilizing techniques such as massively parallel sequencing have been promising and could be used to identify novel virulence determinants of disease in the mammalian host or persistence in the tick vector. Continued research on this unique pathogen and its specific interaction with host and vector may have far reaching consequences and provide insights for diverse disciplines including ecology, infectious disease, and immunology. Here, several reviews will discuss the most recent advances and future studies to be undertaken in the field of B. burgdorferi biology.

Well-written, readable, and superbly illustrated, Cellular and Molecular Immunology, 10th Edition, continues the tradition of excellence established through multiple editions of this bestselling text. Offering an unparalleled introduction to this complex field, it retains a practical, clinical focus while updating and revising all content to ensure clarity and comprehension, bringing readers fully up to date with new and emerging information in this challenging area. It's an ideal resource for medical, graduate, and undergraduate students, as well as a trusted reference for physicians and scientists. - Highlights the implications of immunologic science for the management of human disease, emphasizing clinical relevance throughout. - Employs a highly accessible writing style that makes difficult concepts easier to understand, and provides clear implications of immunologic science to the management of human disease and clinical practice. - Features updates from cover to cover, including new information on intracellular sensors of innate immunity, therapeutic use of monoclonal antibodies, regulation of migration events during T cell-B cell interactions, regulatory and transcriptional events in germinal center formation, immunology of infectious diseases including coronaviruses, human immunodeficiency disorders, and immunology of HIV. - Provides a highly visual, full-color description of the key immunologic and molecular processes with a fully updated, comprehensive, and consistent art program, including many new and extensively revised illustrations. - Helps readers grasp the details of experimental observations that form the basis for the science of immunology at the molecular, cellular, and whole-organism levels and draw the appropriate conclusions. - Includes summary boxes that assist with rapid review and mastery of key material.