The innate immune response to pneumococcal lung infection: the untold story

The host immune response to pneumococcal lung disease has generally been characterised as an intense inflammatory reaction, initially involving resident alveolar macrophages, followed by a heavy infiltration of neutrophils into infected lungs. However, in recent years, more attention has been paid to aspects of innate immunity other than phagocytic cells. It has emerged that complement and surfactant proteins, Toll-like receptors and even T cells have a crucial role. Recent advances in in vivo infection studies enable further insight into these often overlooked basic host immune interactions with invasive pneumococci.