Immunosuppression in established humoral responses

Autoantibodies and circulating immune complexes are common associated findings in inflammatory disease of unknown aetiology. In most circumstances, however, it is far from easy to demonstrate their pathogenic significance. Sometimes pathological events can be linked clearly with the presence of autoantibodies. These include antibodies found in autoimmune haemolytic anaemia and myasthenia gravis. On the other hand, in a host of other diseases the precise mechanism of tissue injury and inflammation is understood only in the vaguest conceptual terms. For this reason it is important to consider the mechanism of action of cytotoxic chemotherapeutic agents that have beneficial effects in these diseases.