Murine Model of Epicutaneously-Induced Immunomodulation

The skin, as the largest organ in the human body interfacing with the external environment, plays crucial physiological roles, including (1) protecting the organism from xenobiotics and microorganisms, (2) facilitating thermoregulation, (3) maintaining water and electrolyte balance, (4) synthesizing vitamin D, and (5) participating in immunity. This paper highlights the skin's pivotal involvement in immunological mechanisms, showcasing its capacity to immunomodulate by suppressing or potentiating the immune response. Previous findings reveal that, in mice, epicutaneous (EC) immunization with an antigen, either alone or in conjunction with pathogen-associated molecular patterns (PAMPs), can suppress or potentiate immune responses, respectively. Specifically, it was observed that EC immunization with an antigen can suppress immune responses in various murine models of autoimmune diseases or allergic contact dermatitis. The results indicate that EC immunization with an antigen combined with PAMPs could serve as an effective strategy to boost immunity against pathogens or alleviate T helper type 2 lymphocyte (Th2)-dependent allergies. This protocol outlines a method for inducing skin suppression via the epicutaneous application of an antigen in a murine model of human allergic contact dermatitis (ACD)-contact hypersensitivity (CHS) mediated by Th1 cells. However, it can also be applied to various murine disorder models. The article presents EC-induced immunomodulation as an attractive murine model for needle-free immunotherapy across various disorders.