The crown-of-thorns starfish (Acanthaster planci) feeds on corals, so extermination and other measures are used to protect ecosystems from this predation. However, red sea bream (Pagrus major) reared with crown-of-thorns starfish showed improved growth, increased phagocytic activity of leukocytes, and improved survival in a challenge test using Edwardsiella tarda, which is highly pathogenic to sea bream. These findings suggest that starfish mucus contains a substance that can improve disease resistance in red sea bream. This substance was isolated and identified using nitric oxide (NO) productivity of mouse-derived macrophage cells (RAW264) as an indicator. The immune-activating substance was identified to be a polymeric compound, possibly a polysaccharide. This substance was then purified, resulting in a molecule of molecular weight 1.81 x 105. The monosaccharides in the polysaccharide were identified and quantified, and l-fucose, d-arabinose, d-mannose, d-glucose, d-galactose, N-acetyl-d-glucosamine, and N-acetyl-d-galactosamine were detected. The purified polysaccharides were examined in the RAW264 cell line using antibodies against Toll-like receptors (TLRs) and were found to stimulate TLR4 – a receptor for pathogens – and activate the immune system. These results indicate that polysaccharides in starfish mucus have a positive effect on growth and immunity in fish.

Content of embryo-specific ƒ¿-globulin in fetal and neonatal sera and sera form adult humans with primary carcinoma of the liver, Vop. Med.