A Toll for DNA vaccines

摘要

The mammalian protein that triggers an innate immune response to bacterial DNA has been identified. This discovery may help in understanding and improving DNA-based vaccines. Innate immunity enables an organism to respond rapidly to invading microorganisms. To do this, the innate immune system uses receptor proteins that can recognize a microbial pathogen by the molecular patterns it displays. There are many pattern-recognition molecules that are involved in innate responses to microbial lipids and carbohydrates. Bacterial DNA is also a potent inducer of innate immunity, but how is such DNA recognized and distinguished from the DNA of the host organism? On page 740 of this issue, Hemmi and colleagues provide an answer. They have identified a mammalian protein—Toll-like receptor9 (TLR9)—that recognizes a specific pattern in bacterial DNA.