The innate immune response to HIV-1: to sense or not to sense

The immune responses to viruses provide a means to quickly alert the host to the presence of an invader, activating a range of intrinsic and adaptive antiviral mechanisms. Several research groups have made advances in understanding the innate immune response to HIV-1, although their findings differ. Some investigators find that the virus slips under the radar of the pattern recognition receptors that sense viruses by co-opting host factors that restrict accessibility of the viral nucleic acids, while others find that the virus is sensed and activates a type-I interferon response. This article reviews the recent findings and discusses the similarities and differences.