Foreword

The lung is the largest surface area of the body in contact with the external environment and it is constantly exposed to a wide array of microbes and particles. As a result the body’s immune system evolved a series of systems which enables it to distinguish potentially harmful agents from those which are innocuous. Two of the major systems are the adaptive and innate immune responses. The innate system is fast responding and recognizes a wide variety of potentially noxious stimuli coming into the lungs. In the majority of cases these may be microbial products, however on occasion the innate immune system can also respond to host-derived danger signals not normally encountered in the healthy lung. A key component of this response is the germ-line encoded pattern recognition receptor family of Toll-like receptors. TLRs regulate the lung’s response to potential pathogens or other environmental hazards and communicate closely with the adaptive immune response to orchestrate effective resolution of infection and a return to homeostasis. Our understanding of the role of TLRs in infectious, environmental and genetic lung diseases has advanced greatly over the last fifteen years. In this book experts from around the world offer their insights into the mechanisms of TLR-mediated responses in a number of common but serious diseases of the lung, and explore how our growing knowledge of the mode of action of TLRs can be exploited for therapeutic use.