The immunostimulatory activity and stability of grass carp (Ctenopharyngodon idellus) roe lectin

A hexameric rhamnose-specific lectin with a molecular mass of 205 kDa and exhibiting some N-terminal sequence similarity to other fish lectins was isolated from roe of the grass carp (Ctenopharyngodon idellus) by affinity chromatography on rhamnose-Sepharose and ion exchange chromatography by fast protein liquid chromatography on a Mono S column. The lectin exhibited mitogenic activity toward murine splenocytes with a potency lower than that of the plant lectin ConA. It exerted a stimulatory effect at a concentration of 10 μg/ml on the phagocytic activity of seabream (Sparus sarba) macrophages. It was unstable toward heat (temperature ≥40 °C), acid (0.1 M HCl), alkali (0.1 M NaOH), trypsin and succinylation.