Figure 3.

Effect of protease‐treated royal jelly (pRJ) on antigen‐specific mucosal IgA response and effect of pRJ or its diethyl ether extract on induction of gp2 expression. (a) Immunization schedule for cynomolgus macaques. Two cynomolgus macaques (Nos. 3 and 4) were orally immunized on days 2, 5, 9, 12, 16, and 19 with fetuin (1 mg) with pRJ (240 mg). Another two macaques (Nos. 1 and 2) were orally immunized with only fetuin on days 2, 5, 9, 12, 16, and 19. Stool sampling was performed on days 1, 12, and 20. This study (permission no. B24‐241) was approved and conducted in accordance with the guidelines of the Animal Care and Use Committee of Kumamoto University. (b) Stool samples (1/100 dilution) were examined to investigate whether anti‐fetuin mucosal IgA level can be raised in cynomolgus macaques by anti‐fetuin ELISA. Significance (repeated measures ANOVA) is indicated as follows: **, P < 0.01. The error bars denote the standard deviation. (c) To examine the RJ activity of pRJ that enhances gp2 expression in the in vitro Caco‐2 monolayer, the Caco‐2 monolayer treated with DMSO or pRJ (0.85 mg/mL) was subjected to flow cytometry using the anti‐gp2 antibody. (d) To investigate the effect of the diethyl ether extract of pRJ on the induction of gp2 expression, the Caco‐2 monolayer treated with the diethyl ether extract of pRJ (0.85 mg/mL) was subjected to flow cytometry using the anti‐gp2 antibody.