immuunikompleksivälitteiset

immuunikompleksivälitteiset refers to a type of hypersensitivity reaction mediated by the formation and deposition of immune complexes. Immune complexes are aggregates formed when antigens bind to antibodies. Normally, these complexes are efficiently cleared from the body by phagocytic cells. However, in certain situations, their formation can exceed clearance capacity, leading to their deposition in tissues, particularly in small blood vessels.

Once deposited, these immune complexes can activate the complement system, a cascade of proteins that plays a crucial role in the immune response. Complement activation triggers inflammation by attracting immune cells like neutrophils to the site of deposition. These inflammatory cells release enzymes and other mediators that can damage the surrounding tissues.

The clinical manifestations of immuunikompleksivälitteiset reactions depend on the location where the immune complexes are deposited. Common sites include the kidneys (leading to glomerulonephritis), skin (causing vasculitis or urticaria), joints (resulting in arthritis), and serous membranes. Examples of conditions associated with this mechanism include serum sickness, lupus nephritis, and certain types of vasculitis. Diagnosis often involves detecting circulating immune complexes, complement levels, and evidence of tissue deposition.