Production and characterization of monoclonal antibodies to Treponema pallidum

This study was attempted to produce the monoclonal antibodies specific for Treponema pallidum and to investigate their characteristics, thereby contributing to identify the antigenic structure and to apply the diagnosis of syphilis. The seven clones (YS 3, YS 75, YS 307, YS 481, YS 343, YS 1 and YS 406) secreting monoclonal antibodies reactive with T. pallidum were produced. The isotypes of the seven monoclonal antibodies produced were defined. Optical densities of the 7 monoclonal antibodies were ranged from 0.59 to 1.48 as measured by ELISA. Monclonal antibodies from 5 of the 7 clones which could agglutinate sheep RBC sensitized with T. pallidum, showed strong fluorescences. The monoclonal antibody from YS 343 was cross-reactive with non-pathogenic treponemes, but the other 6 monoclonal antibodies reacted with T. pallidum specifically. On immunoblotting, monoclonal antibodies from 5 of the 7 clones reacted with a polypeptide of a molecular weight of 47 kDa, and monoclonal antibodies from YS 343 reacted with a polypeptide of 64 kDa common to both T. pallidum and T. phagedenis. The above results revealed that 7 clones secreting monoclonal antibodies reactive to T. pallidum were produced successfully, and specific antibodies reacting with major antigenic polypeptides of a molecular weight of 47 kDa would be useful in the diagnosis of syphilis in the future.