Innate Immune System for Diagnostics and Therapy: Progress in Fundamental Knowledge and Clinical Application

The innate immune system was evolutionary designed to protect the organism against various types of pathogens, including bacteria, parasites and viruses. However, in higher organisms the function of innate immune system is not restricted to the host defence and protection against of non-self components. The essential feature of the innate immune system that is required continuously for the haemostatic balance and healthy tissue turnover is the ability of major population of innate immune cells - tissue macrophages - to recognise and eliminate unwanted self components, including apoptotic cells, transformed cells, modified lipoproteins, excess of growth factors, cytokines and extracellular matrix components [1]. In case of pathogen attack or trauma, the innate immune system initiates acute inflammatory reaction and gives signals for adaptive immune cells to amplify the reaction in the antigen-specific ways. Once the danger is eliminated, the innate immune cells coordinate the resolution/healing phase and restore homeostatic balance. During the healing phase, the innate immune system supports angiogenesis, formation of tissue-specific extracellular matrix as well as recruitment and differentiation of somatic cells. The mistakes made by innate immune cells result in a broad range of pathologies, including cancer, cardio-metabolic disorders, allergies and neurodegeneration, and can also lead to the intolerance of implanted materials [2,3]