Beta glucan binding protein and its role in shrimp immune response

Despite their relatively short life and assumed lesser complexity, crustaceans have mechanisms to detect foreign matter. In particular, they appear to recognize common characteristics present in Ž . bacteria and fungi, such as lipopolysaccharides LPS and b-glucans. Although these microbial components can directly activate defensive cellular functions such as phagocytosis, melanization, encapsulation and coagulation, plasma recognition proteins amplify these stimuli. Beta glucan Ž . binding protein BGBP reacts with b-glucans and the glucan–BGBP complex induces degranulaŽ . tion and the activation of prophenoloxidase proPO . This protein is present in all crustaceans studied so far and is highly conserved. Together with LPS-binding agglutinin, BGBP stimulates cellular function only after its reaction with LPS or b-glucans, resembling the secondary activities of vertebrate antibodies. q 2000 Elsevier Science B.V. All rights reserved.