Comparative Study on the Virulence between Vibrio Cholerae of Serogroup 01 and non-01 0139 V. Cholerae
Jiang Lijun; Qao Rong; Wang Yan; Wang Bingrui(Lanzhou Institute of Biological products Ministry of Health, Lanzhou 730046 )
Non-o1 serogroup 0139 Vibrio cholerae is a new causative agent of cholera emergence which has been spreading across Southern Asia Subcontinent since the end of 1992. The comparison of virulence of 0139 V. cholerae with serogroup 01's has an important significance for understanding its characteristics and developing relevant vaccine. The comparative test results of the virulence of four O139 V. cholerae strains with O1 V. cholerae derived from the different nation and area were reported in this paper. It was found that the wide differentials in virulence features are presented between 0139 V. cholerae and 01 serogroup V. cholerae. 0139 strains produce opaque colonies. Optical microscopy of organism morphology reveales a light-stained capsule layer surrounding the cells by capsule staining. Electron microscopic examination of the opaque form of four 0139 stains reveales thick , electron-dense, fibrous capsules surrounding polycationic ferritin-stained cells, the ferritin-stained material around serogroup 01 stains is absent. The encapsulated cells have the high proliferation capacity in vivo and produce enterotoxin. The results of invasion test in vivo showed that all of four 0139 strains lead to bacteriemia. Four 0139 strains are protected from serum bactericidal activity and also has increased virulence in mice. Our data provide the indication that non-01 V. cholerae 0139 strains can have a polysaccharide capsule. This capsule may be important in protecting the organisms from host defenses and may contribute to the ability of some non-01 V. cholerae strains to cause septicemia in susceptible hosts. The mice immunized by the inactivated 0139 vaccine produced the protective effect against the challenge of homogenous strain, therefore, it was shown that the inactivated 0139 cholera vaccine can protect the host from the infection of homogenous V. cholerae strains.
【CateGory Index】： R378