Immunological Analysis Of The Vibrio Parahaemolyticus Lipopolysaccharide(LPS) Against Paralichthys Olivaceus And Analysis Of Immunogenicity

Vibrio parahaemolyticus is a familiar conditional pathogen bacterium in marine; it can induce the disease of fish. The lipopolysaccharide(LPS) is the primary component of the negative Gram bacteria outmembrane, it is the important endotoxin. There are no studies on LPS of V. parahaemolyticus, it has important meaning on study it to the continuable and healthy aquaculture.The LPS was isolated by using phenol-water method from pathogen V. parahaemolyticus that was isolated from sick flatfish P. olivaceus and identified according to the conventional methods. Before immunity there is a test about the LPS toxicity. The results showed inject the dose of 40rng-kg~1 is safety. As antigens LPS is immunized to the health flatfish P. olivaceus by double i.p.injection. The results show that after the fish were inoculated with LPS, its agglutinating antibody liters against dead V. parahaemolyticus increase conspicuously and about 3 week later reaches the highest (256). The phagocytic percentage (PP) of leucocytes in the blood of the immunized increases conspicuously more than that of the control (P<0.05).- The immunised P. olivaceus inject with live V. parahaemolyticus, the protect ratio is 62.5%.Subsequently the component of LPS was analysed with SDS-PAGE and detected with silver stain method, and calculated the molecular weight. The results show that the LPS contain main four bands, which are 41.3KDa, 30.7KDa, 25.4KDa and ll.8KDa, respectively. Inoculated the mice with LPS, its agglutinating antibody titers against LPS reach 1280. The results show the LPS has strong immunogencity.The research has important function to the next study. It is the foundation of develops vaccine for the prevention and cure.