Quantification of lectin in freshwater prawn (Macrobrachium rosenbergii ) hemolymph by ELISA.

Abstract An enzyme-linked immunoabsorbent assay was developed to quantify the lectin present in the hemolymph of the freshwater prawn Macrobrachium rosenbergii . This method involves the use of murine monoclonal IgG1 with κ light chain (designated as 3G1) antibodies raised against the purified lectin, the assay that we developed recognized as little as 30 ng/ml of lectin, and was used to measure the lectin concentration in animals at different maturation stages. The highest concentration of lectin was identified in the hemolymph from post-larval prawns and the lowest in molt stage adult animals. The hemagglutination activity of the lectin was four-fold higher in adult than in juvenile specimens, although in all cases N -acetylated sugar residues, such as N -acetyl- d -glucosamine, N -acetyl- d -galactosamine, and N -acetyl- d -neuraminic acid were inhibitors of the lectin activity, suggesting that lectin plays a role in the transport of N -acetylated sugar in juvenile prawns. Our results indicate that lectin concentration and hemagglutinating activity could be influenced by developmental conditions of the freshwater prawn.