[Autoimmunity. Physiological control mechanisms and pathways to autoimmune disease]

Area of Science:

• Immunology
• Autoimmunity
• T-cell biology

Context:

• Immunological tolerance to self-antigens is crucial for preventing autoimmune diseases.
• Mechanisms include central deletion of autoreactive T-lymphocytes and peripheral regulation by regulatory T-cells (Treg).
• Autoimmune diseases arise from multifactorial disturbances in immune homeostasis, involving genetic and environmental factors.

Purpose:

• To elucidate the complex mechanisms underlying immunological tolerance and its breakdown in autoimmune diseases.
• To explore the role of exogenous and endogenous stimuli in aberrant immune activation.
• To highlight the impact of microbial Toll-like receptor ligands and Th17 cells on immune regulation and autoimmunity.

Summary:

• Autoreactive T-lymphocytes are eliminated in the thymus (negative selection), and regulatory T-cells (Treg) suppress autoimmune responses peripherally.
• Genetic predisposition and external factors like infections or barrier dysfunction disrupt immune homeostasis, leading to autoimmune diseases.
• Microbial Toll-like receptor ligands interfere with immune control, promoting autoreactive B-cell activation, autoantigen presentation, and Treg modulation.
• Interleukin-17 producing Th17 cells are implicated in promoting inflammation and tissue damage in autoimmune conditions.

Impact:

• Understanding these mechanisms is vital for developing targeted therapies for autoimmune diseases.
• This research sheds light on how environmental factors can trigger or exacerbate autoimmune conditions.
• Identifying the roles of specific immune cells and molecular pathways offers potential therapeutic targets.