tolerogens

Tolerogens are substances that induce immune tolerance, a state of unresponsiveness of the immune system to a specific antigen. Unlike immunogens, which elicit an immune response, tolerogens prevent or suppress such responses. This tolerance can be central, occurring during immune cell development in the thymus or bone marrow, or peripheral, where mature immune cells are rendered unresponsive in the periphery.

The mechanism by which tolerogens induce unresponsiveness involves several pathways. These can include the induction of T regulatory cells (Tregs), which actively suppress immune responses, or the induction of clonal anergy, a state where lymphocytes become unresponsive. Another mechanism is clonal deletion, where antigen-specific lymphocytes are eliminated. The specific outcome depends on the dose, route of administration, and the nature of the antigen.

Tolerogens have significant implications in medicine. They are explored for treating autoimmune diseases, where the immune system mistakenly attacks the body's own tissues. By inducing tolerance to self-antigens, tolerogens could potentially halt or reverse these conditions. They are also investigated for preventing transplant rejection, aiming to make the recipient's immune system tolerant to the donor organ, and for mitigating allergic reactions, where the immune system overreacts to harmless substances. Research into the development and application of tolerogens continues to be an active area in immunology and immunotherapy.