Study of capsular polysaccharide from Vibrio parahaemolyticus.
The leading cause of food poisoning in both Taiwan and Japan is Vibrio parahaemolyticus infection, whose mechanism of enteropathogenesis is still unclear. To evaluate whether surface components are responsible for the intestinal adhesion of V. parahaemolyticus, we have developed a novel method for isolating the capsular polysaccharide (CPS) from V. parahaemolyticus (serotype O4:K8). We found that culturing of V. parahaemolyticus in broth for 1 week or more changed the colony form of the bacteria on an agar plate from opaque to translucent. The translucent colonies of V. parahaemolyticus contained little CPS and exhibited a much lower level of adherence to epithelial cells (Int-407) than the opaque colonies of the bacteria. Incubation of V. parahaemolyticus in medium supplemented with bile increased the levels of CPS and adherence. Treatment of V. parahaemolyticus with anti-CPS but not anti-LPS serum decreased the level of bacterial adherence. In addition, purified CPS bound to epithelial cells in a dose-dependent manner. Intranasal administration of CPS to mice in the presence of adjuvants such as immunostimulatory sequence oligodeoxynucleotides or cholera toxin elicited CPS-specific mucosal and systemic immune responses. These results indicate that CPS plays an important role in the adherence of V. parahaemolyticus to its target cells and may be considered a potential target for the development of a vaccine against this pathogen.
Hsieh
Yu-Chi
YC
Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan 11529.
Liang
Shu-Mei
SM
Tsai
Wan-Ling
WL
Chen
Yee-Hsiung
YH
Liu
Teh-Yung
TY
Liang
Chi-Ming
CM
D000818:Animals; D001422:Bacterial Adhesion; D016667:Bacterial Capsules / Q000276:immunology / Q000302:isolation & purification / Q000502:physiology*; D001428:Bacterial Vaccines / Q000276:immunology; D002460:Cell Line; D005260:Female; D006801:Humans; D007422:Intestines / Q000382:microbiology; D051379:Mice; D008807:Mice, Inbred BALB C; D014736:Vibrio parahaemolyticus / Q000502:physiology*
D001428:Bacterial Vaccines