Autoantibodies directed against various self-antigens comprise a heterogeneous group of immunoglobulins, which differ in their qualitative and quantitative features. An important qualitative characteristic of antibodies is affinity/avidity, which changes in the process of its maturation during the immune response.This study is aimed to summarize the knowledge about avidity of selected autoantibodies in certain autoimmune diseases. The avidity of various autoantibodies differs under distinct clinical situations. High-, moderate or low-avidity may be found in biological fluids in patients with autoimmune diseases.The avidity maturation associated with progression from low to high values typical for antibodies against exogenous antigens is not always uniform in autoimmune diseases; therefore, the avidity of each autoantibody should be judged individually. Some studies promise the possible benefit of avidity examination for the refinement of diagnosis and prediction of selected autoimmune diseases.Key words: affinity - anti-citrullinated protein antibodies - anti-glomerular basement membrane antibodies - anti-glutamate decarboxylase antibodies - anti-insulin antibodies - autoantibodies - avidity - onconeuronal antibodies.

Avidity of anti-phospholipid antibodies in relation to their levels