Introduction on Nuclear Medicine and Immunology

Molecular nuclear medicine imaging techniques get a foothold in the diagnosis and treatment response monitoring of various immune-mediated diseases. Several specific radiopharmaceuticals can be used to improve diagnosis, staging, therapy decision-making, and follow-up of infectious, inflammatory, and oncological diseases where immune cells are involved. Several efforts made in the field of nuclear medicine in recent decades have made it possible to evaluate molecules playing a central role in the development of such immune-mediated conditions. The application of molecular imaging techniques may set the stage to assess the expression of the specific molecular targets at the disease site and quantify their presence, giving us a better understanding of the pathogenesis and cellular network of the infective/inflammatory or neoplastic diseases and thus providing an indispensable tool for an individualized therapy decision-making, avoiding side effects and improving therapeutic approaches. In this chapter, we have summarized the immune system, its main building blocks, its innate and adaptive arms, and the role it plays in the development and/or elimination of inflammation, infection, and malignancy. Moreover, the links between the fields of nuclear medicine and immunology, projecting as the procedures for the detection of infection, inflammation, and malignancy, radioimmunoimaging, and radioimmunotherapy, will be discussed.