EARTHWORM IMMUNE-RESPONSES

The knowledge of the immunity in annelids starred with the use of eart hworms as biomarkers indicating changes caused by environmental pollut ion. Defence strategies effectively protect earthworms against bacteri al infections and parasitic invasion. A natural immunity formed by ana tomical and chemical protective barriers prevents damage of the underl ying tissues, body fluid losses, and microbial infections of the body cavity. The internal defence mechanisms of annelids involve phagocytos is, nodule formation and encapsulation, blood coagulation and wound re pair, and antibacterial immune proteins. The antibacterial activity of coelomic fluid associated with lysozyme-like substances and inducible humoral molecules support haemocytic reactions in the annelid defence system.