What is the Origin of Immunological Tolerance?

This concept is fundamental to immunology, stemming from early transplantation research and later elucidated through detailed studies of central and peripheral immune regulation checkpoints. In the hormonal context, its failure is directly implicated in the pathogenesis of organ-specific autoimmune diseases affecting the pituitary, adrenals, or islets of Langerhans.

What is the Mechanism of Immunological Tolerance?

Central tolerance mechanisms involve the rigorous negative selection of developing lymphocytes within the thymus and bone marrow, eliminating those strongly reactive to self-peptides presented by MHC molecules during maturation. Peripheral tolerance mechanisms, such as the active suppression mediated by regulatory T cells (Tregs) or the induction of anergy through inhibitory receptors like CTLA-4, suppress self-reactive cells that manage to escape central screening. This dual system actively maintains endocrine gland integrity against autoimmune attack.

Immunological Tolerance ∞ Area

Immunological Tolerance

Meaning

Immunological Tolerance describes the specialized state of unresponsiveness of the adaptive immune system toward substances or tissues that possess the potential to induce an immune response, specifically self-antigens present within the body’s own endocrine tissues. This mechanism is fundamentally essential for preventing autoimmune pathology where the immune system mistakenly attacks hormone-producing cells like those in the thyroid or pancreas. Achieving both central and peripheral tolerance ensures self-reactive lymphocytes are appropriately deleted or functionally silenced.