2001 年 20 巻 1 号 p. 1-8
Probiotic bacteria are important functional foods capable of improving consumer health. Although most probiotic bacteria are derived from human intestinal flora, they are not indigenous to all individuals. It is very likely that probiotic bacteria are seen as exogenous or foreign antigens by the gut immune system. In research on orally administered lactic acid bacteria, it was found that serum antibody responses were induced not only against the whole bacterial cell, but also against cytoplasmic components. Mucosal immune responses were induced against cytoplasmic antigens and may be of relevance in the development of mucosal vaccines using lactic acid bacteria. These bacteria also exert an adjuvant effect on the mucosal IgA response against not only pathogenic organisms, but also dietary antigens. Furthermore, they enhance systemic immune responses such as phagocytic activity and serum antibody production. These biological responses have been shown in human studies and have formed the basis for oral bacteriotherapy with probiotic bacteria. Since the immunopotentiating activity of lactic acid bacteria is strain-dependent, it is important that special efforts be directed to selection criteria used for the identification of biologically active strains with probiotic function.