Abstract: Bacillus subtilis was a Gram-positive bacteria, and also a non-pathogenic strain, which could form spores. It was a hypopus that could withstand extreme conditions and other noxious chemicals. B.subtilis, with a monolayer cells outer membrane and endotoxin-free cell wall, could efficiently secret large amounts of heterologous proteins out of the membrane directly within animal intestine. B.subtilis as a probiotic, lived in the gut of its host, had the capacity to maintain the balance and stability of the intestinal environment and stimulate the animal to release secretory immunoglobulin. All those above advanced the local immunity of the intestinal mucosa and further enhanced the immunity. Currently,B.subtilis became an ideal vaccine vector to the preparation of mucosal immune vaccine because of its unique advantages to humoral and cellular immune. Gradually, B.subtilis, as a vaccine vector that popularized easily, turn out to be a hot research object. Here, the present study was conducted to illustrate the mechanism of mucosal immune, research progress and application prospects of B.subtilis that worked as a vaccine vector.

Key words: Bacillus subtilis; vaccine; immunity; vector