Abstract: At the different stages of Treponema pallidum (TP) infection, cellular and humoral immunity are partly involved. T-cell-mediated immune response is considered to be dominant, while serum antibodies are only partially protective with different degree of immune suppression. The humoral and cellular immune responses  play an important role in the clearance of TP during early syphilis, while the cellular immune response mainly causes tissue damage at the late stage. In this paper, the update of the immunogenicity of TP the body's immune response to TP infection and immune evasion of TP are reviewed.

Key words: syphilis, immunopathogenesis, cytokines, immune evasion