Sequence-specific activation of the DNA sensor cGAS by Y-form DNA structures as found in primary HIV-1 cDNA.

Cytosolic DNA that emerges during infection with a retrovirus or DNA virus triggers antiviral type I interferon responses. So far, only double-stranded DNA (dsDNA) over 40 base pairs (bp) in length has been considered immunostimulatory. Here we found that unpaired DNA nucleotides flanking short base-paired DNA stretches, as in stem-loop structures of single-stranded DNA (ssDNA) derived from human immunodeficiency virus type 1 (HIV-1), activated the type I interferon-inducing DNA sensor cGAS in a sequence-dependent manner.

RIG-I detects triphosphorylated RNA of Listeria monocytogenes during infection in non-immune cells.

The innate immune system senses pathogens by pattern recognition receptors in different cell compartments. In the endosome, bacteria are generally recognized by TLRs; facultative intracellular bacteria such as Listeria, however, can escape the endosome. Once in the cytosol, they become accessible to cytosolic pattern recognition receptors, which recognize components of the bacterial cell wall, metabolites or bacterial nucleic acids and initiate an immune response in the host cell.

Delivery with polycations extends the immunostimulant Ribomunyl into a potent antiviral Toll-like receptor 7/8 agonist.

Background: Upper respiratory tract infection is a frequent cause of morbidity worldwide. Although the course of infection is usually mild, it is responsible for enormous social and economic costs. Immunostimulation with bacterial extracts consisting of ribosomal RNA and proteoglycans, such as Ribomunyl, was introduced into the clinic in the 1980s as a new treatment concept, but did not achieve widespread application.

Epigenetics and transplantation: clinical applications of chromatin regulation.

Epigenetics is a field that has swiftly gained momentum over the past few years. It has been associated with applications in development, evolution and pathogenesis. In recent studies, however, a link has surfaced that connects epigenetic changes and transplantation.

Recognition of 5' triphosphate by RIG-I helicase requires short blunt double-stranded RNA as contained in panhandle of negative-strand virus.

Antiviral immunity is triggered by immunorecognition of viral nucleic acids. The cytosolic helicase RIG-I is a key sensor of viral infections and is activated by RNA containing a triphosphate at the 5' end. The exact structure of RNA activating RIG-I remains controversial.