Molecular mechanisms of the shrimp clotting system

Shrimp, like other invertebrates, relies solely on its innate immune system, to combat invading pathogens. The invertebrate immune system has ancient origins that involve cellular and humoral responses. The clotting system of the humoral immune response is the first line of defense against pathogens and also serves to prevent blood loss during injury and wound healing. Tranglutaminase and clotting protein are molecules involved in the blood clotting system of crayfish and shrimp. Studies have shown that the shrimp clotting system is linked with the activation of antimicrobial peptides, similar to that of the horseshoe crab. Unlike the horseshoe crab and crayfish blood coagulation which are well studied systems, blood clotting in shrimp remains poorly understood. Here we review the shrimp clotting system and its involvement in innate immunity.