Our body's immune system constantly faces the decision of whether to activate immune responses (immunity) or regulate (suppress) them (tolerance). When this finely tuned immune homeostasis is disrupted, various immune disorders arise. Particularly, immune hypersensitivity leads to allergic diseases such as atopic dermatitis and asthma, as well as autoimmune diseases like rheumatoid arthritis and juvenile diabetes. Therefore, in our laboratory, we investigate the mechanisms underlying the maintenance of immune homeostasis at the molecular and cellular immunological levels. Specifically, we conduct research to develop and elucidate the mechanisms of action of gut-targeted immunomodulatory agents that can control immune hypersensitivity reactions.