Innate Immune Responses in HIV-Infection

The immune system comprises complex cellular and humoral systems, which are forming an interactive network to recognize and eradicate invading pathogens. Foreign molecules present on viruses, bacteria and parasites, but not on host cells, are discriminated from self through pathogen-associated molecular patterns. Upon entry of the pathogen into the body immediate non-specific immune responses are triggered and within a short time the innate immune system is completely activated. The innate immune system is composed of multiple humoral and cellular players, including cytokines, complement proteins, acute-phase proteins, dendritic cells, macrophages, NK cells, that co-operate in a complex to generate an efficient defense against infection (Figure 1). At best, these immediate innate immune responses are able to clear infection or bridge the period until the adaptive, specific immune response is taking effect.