Beschreibung:
<jats:sec><jats:label /><jats:p>Although sufficient intake of protein and amino acids is essential for normal immune functions, it has not been elucidated well whether dietary glutamic acid (Glu), the most abundant amino acids in food proteins, plays any roles in the maintenance of immune functions or not. Therefore, this study aimed to assess the effect of removal of Glu from the diet on mucosal and systemic immune responses in immunized mice.</jats:p><jats:p>Female BALB/c mice were divided into two dietary groups, and were given amino acids defined diet (control) or Glu‐free diet during one‐week acclimation period and successive immunization period. The mice were orally immunized with 2mg of keyhole limpet hemocyanin (KLH) and 10μg of cholera toxin (CT) on day 0, 10 and 20 or systemically immunized (i.p.) with 100μg of KLH and 1μg of CT on day 0 and 14 (n=5 for each). One week after the last immunization, plasma samples were collected to measure KLH‐specific antibody titer by ELISA. Lamina propria lymphocytes (LPL) were harvested to assess their IgA‐secretion in vitro (ELISPOT assay).</jats:p><jats:p>Feeding of Glu‐free diets reduced the elevation of antigen‐specific antibody titer in plasma in orally immunized mice, which was accompanied with reduced IgA‐secreting activity in mucosa. Besides, there was no effect in the responses against systemic immunization. These results suggest nutritional roles of Glu in the maintenance of normal mucosal immune response.</jats:p></jats:sec>