proteiinivastaainekompleksi

Proteiinivastaainekompleksi, also known as an antigen-antibody complex, is a molecular aggregate formed when an antibody binds to its specific antigen. Antibodies are proteins produced by the immune system to identify and neutralize foreign substances, such as bacteria, viruses, and allergens. Antigens are typically molecules found on the surface of these foreign invaders. The binding between an antibody and its antigen is highly specific, similar to a lock and key mechanism.

When an antibody recognizes and binds to an antigen, it forms a stable complex. This interaction is crucial for various immune responses. For instance, antigen-antibody complexes can activate the complement system, a cascade of proteins that helps clear pathogens and infected cells. They can also facilitate the phagocytosis of pathogens by immune cells like macrophages and neutrophils, as these cells have receptors that can bind to the antibody portion of the complex.

The formation of these complexes plays a significant role in diagnostic tests, such as ELISA (Enzyme-Linked Immunosorbent Assay) and Western blotting, which are used to detect the presence of specific antigens or antibodies in biological samples. In some cases, the accumulation of antigen-antibody complexes can also contribute to the development of autoimmune diseases or immune complex-mediated glomerulonephritis, where the body's own tissues are mistakenly targeted. The precise structure and function of these complexes are a subject of ongoing research in immunology and medicine.