Preliminary Study On The Cloning And Expression Of Cholera Toxin B Subunit Gene In Bifidobacterium Bifidum

BackgroundCholera is a violent communicable disease caused by Vibrio cholerae. It is the prevention and control emphasis of communicable disease in many countries. Vaccination is the most effective measures to prevent Cholera. Previous injection vaccines had many defects in different degrees. Studies showed that the vaccines of enteric communicable disease such as Cholera were more efficient by administering immunogens orally rather than parenterally. So, it had became the hot spot of developing safe, convenient, inexpensive oral vaccine. The studies of gene recombination oral vaccine based on Cholera toxin(CT) had became the main direction of Cholera vaccine. CT is the main causative agent of Cholera. Its molecular weight is about 84KD. It is composed of one A subunit(CTA) and five same B subunits(CTB). CTA is the toxic subunit, CTB are the nontoxic subunits and the main protective antigen of Cholera. CTB can stimulate mucoantibody and serum antibody of people and animals to prevent Cholera after orally administering. On the other hand, CTB is a very good immunologic adjuvant. It can intensify haptenic immunogenicity such as polysaccharides and little peptid. It can promote mucosae immune reaction of other antigens when used with other incorrelate antigen. This will...