[Escape mechanism of intracellular parasitic bacteria and prospect of new approach to infection control].

Intracellular parasitic bacteria are capable of escaping from the intracellular killing inside macrophages by virtue of highly sophisticated molecular mechanism. Because of the escape from phagocytic defense, infection caused by these bacteria is difficult to be controlled even in the presence of normal host defense system. In order to understand the mechanism of intracellular parasitism of particular types of bacteria, the basic mechanism of intracellular killing inside phagocyte and the strategy of escape by some representative intracellular bacteria are reviewed. Based on the mechanism of T-cell dependent protective immunity, some possible approaches to the infection by intracellular bacteria, especially to tuberculosis, have been discussed.