Science: "Listening to" bacterial dialogue, another evolutionary strategy of an "arms race" between somatic cells and bacteria.

Recently, researchers at the Max Planck Institute for infectious biology in Berlin have discovered that somatic cells have a special receptor that can't recognize bacteria themselves, but can detect bacterial communication in order to adjust immune strategies.the results of the study were published in the journal Science.DOI:10.1126/science.aaw1629 There are a lot of opportunistic pathogens in the environment. For these pathogens, the infection threshold is particularly high. Only when the pathogens appear in a high number to form pathogenic substances, can the obvious pathogenic effect occur.Pseudomonas aeruginosa is such a kind of bacteria, we often contact with it, it mainly exists in water pipes, wash basins and other wet places, but also can parasitize in the human body. When the body resistance is low, a large number of Pseudomonas aeruginosa will lead to serious diseases, such as pneumonia, meningitis, urinary tract infection and septicemia.because of its high resistance to antibiotics, the diseases caused by it are difficult to treat.the timing of bacterial attacks stems from a small molecule called "quorum sensing molecule", in which bacteria can communicate with each other.only when the bacteria reach enough density can they produce pathogenic substances and mucus molecules, thus protecting them from antibiotics and the body's own immune system.then does the body have the coping strategies against the outbreak of pathogens? By analyzing the infection process of Pseudomonas aeruginosa in zebrafish, mice and human cells, the researchers found that host cells could detect the communication between bacteria through aromatic receptor (AHR).the receptor monitors quorum sensing molecules, enabling somatic cells to detect when bacteria are ready to attack, thereby activating the immune system when it is necessary to resist the invasion of these bacteria.the host aryl hydrocarbon receptor (AHR) "monitors" bacterial communication.in the early stage of monitoring, AHR is inhibited, which can prevent the early mobilization of immune defense and save energy of host.only when the number of bacteria reaches the critical level, can the body gather the energy needed for defense to carry out immune defense process.at the same time, it also helps to prevent additional damage caused by the immune system reaction.these results demonstrate the reaction mechanism between host AHR and bacterial quorum sensing, which can pave the way for host specific therapy in some infectious diseases in the future, not only for the type of infection, but also for the specific stage of the disease.end reference: [1] host monitoring of quorum sensing Pseudomonas aeruginosa effect [2] body cells spy out bacterium