Searching for meningococcal antigens with vaccine potential

• Main Authors: Chih-Chen Tao, 陶致蓁
• Other Authors: Lee-Feng Chien
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/99536758123037108004

碩士 === 國立中興大學 === 生命科學系所 === 95 === Neisseria meningitidis is a Gram-negative, encapsulated bacterium that has been classified into five major pathogenic serogroups (A, B, C, Y,and W-135) on the basis of the chemical composition of distinctive capsular polysaccharides. N. Meningitidis is a major cause of sepsis and meningitis. At present, polysaccharide vaccines are available for prevention of disease caused by serogroup A, C, Y,and W-135 strains. There is no promising vaccine to prevent N. meningitidis serogroup B (GBM). Because the capsular polysaccharide of serogroup B is composed of a homolinear polymer α（2-8）N-acetyl（N-Ac）B3B neuraminic acid (polysialic acid),which is similar to NCAM of human neural cell, using serogroup B polysaccharide as vaccine will possibly result in autoimmunity. In this study, we constructed an expression library with chromosomal DNA from Neisseria spp. and screened by anti-rat NM serum. The result will be distinguished by the antibody while selecting bone to 7 separately but present single bacterial strain of positive reaction. After analysis each of nucleic acids, including: RplL (HT50S ribosomal protein L7/L12TH, NMB0131), LpdA1 (lipoamide dehydrogenase, NMB0957), DsbA-1 (thiol:disulfide interchange protein, NMB0278), DsbC (thiol:disulfide interchange protein, NMB0550), DsbA-2 (thiol:disulfide interchange protein, NMB0294), pilE (pilin, NMB0018) and Laz (lipid modified azurin protein, NMB1533). Because RplL and LpdA1 is the metabolic protein, PilE has the highly variations, DsbA is a lipoprotein location in inner-membrane, it is unsuitable to make it for the good antigen. Though Laz is the ideal surface antigen, but forefathers study and show that can not cause the effective complement-mediated bactericidal activity, it is not good to protect the result. So select DsbC among them to over expressing in E.coli, then prepare its antiserum anti-rDsbC to analyse this basic characterizations in Neisseria spp. Western blotting show that DsbC was expressed in all bacterial strain, and is mainly distributed among the preriplasm and cytoplasim. Exist in the inner-membrane or outer-membrane on a small quantity. There is no obvious complement -mediated bactericidal activity but this protein really has Dsb enzyme activation.