Bacterial DNA contains a much higher frequency of CpG dinucleotides than are present in
mammalian DNA. Furthermore, bacterial CpG dinucleotides are often not methylated. It is
thought that these two features in combination with specific flanking bases constitute a CpG
motif that is recognized as a “danger” signal by the innate immune system of mammals and
therefore an immune response is induced when these motifs are encountered. These
immunostimulatory activities of bacterial CpG DNA can also be achieved with synthetic CpG …